CAI + Throttle body spacer + intake manifold spacer = No MPG increase.
05-19-2008, 08:56 AM
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CAI + Throttle body spacer + intake manifold spacer = No MPG increase.
Hey guys,
Just installed the Injen CAI alongside the Outlaw Engineering Throttle body spacer and Intake manifold spacer. On my way to and from work I generally average 30-33 mpg. If I'm having fun on the tank it's around 21.
No reving / horseplay I still only got 31 mpg. So... Hopefully the underdrive/lightweight pulley will help because this was a bit of a disappointment.
(reported 1-2 on the intake, 1-2 on the spacers...)
This is with one tank.
(04 MT TL)
Soon I'll clean the throttle body / plenum / intake... looked like there was a little carbon build up. I'll try re-sealing the plenum cover...Maybe there's some leakage.
Also, getting an exagerated whistle on the intake, if anyone knows a solution I posted about it here:
https://acurazine.com/forums/showthread.php?t=180514
Regards,
Rob M.
Just installed the Injen CAI alongside the Outlaw Engineering Throttle body spacer and Intake manifold spacer. On my way to and from work I generally average 30-33 mpg. If I'm having fun on the tank it's around 21.
No reving / horseplay I still only got 31 mpg. So... Hopefully the underdrive/lightweight pulley will help because this was a bit of a disappointment.
(reported 1-2 on the intake, 1-2 on the spacers...)
This is with one tank.
(04 MT TL)
Soon I'll clean the throttle body / plenum / intake... looked like there was a little carbon build up. I'll try re-sealing the plenum cover...Maybe there's some leakage.
Also, getting an exagerated whistle on the intake, if anyone knows a solution I posted about it here:
https://acurazine.com/forums/showthread.php?t=180514
Regards,
Rob M.
05-19-2008, 09:05 AM
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Right... Understandable. However, I've already maxed out my mileage using good driving habits. I was hoping to net a few more with these mods.
This is simply a post for people (like me) who were tricked by reports of these mods boosting mileage.
30-33's not bad... But with rising gas prices A 2-4 mpg increase is pretty important.
-Rx
This is simply a post for people (like me) who were tricked by reports of these mods boosting mileage.
30-33's not bad... But with rising gas prices A 2-4 mpg increase is pretty important.
-Rx
05-19-2008, 09:16 AM
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I completely agree with you. I bought my first CAI hoping for the acclaimed 1-2 MPG. I saw a slight improvement but I mostly drive that car around town, with relatively spirited driving, so that disappeared.
The only thing that will give you an increase in MPG is shedding weight and/or easing up on the gas.
05-19-2008, 11:08 AM
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Um... What is that theory based on?
That's like saying the only way to gain horse-power is by decreasing weight and pressing harder on the gas.
I'm not saying you're wrong... Those are definitely two ways to increase mileage...
But...
Theoretically, air intakes should have an effect on your vehicles mileage. Changing the air / fuel mixture will alter the efficiency of the engine for better or worse.
The thermal spacers definitely (absolutely) work wonders for isolating temperature. My CAI was cold to the touch this morning (after driving 23 miles), as well as the throttle body. The plenum was probably about 85 degrees. As a comparison, when I went to do the mod I had to wait over an hour with the hood open just so I could touch the throttle body... Never mind the plenum. A HUGE temperature difference like this will absolutely change the characteristics of air-flow in the area... Cold air turning to warmer and warmer air (at least from the physics standpoint) will increase resistance as the volume expands. Decreased expansion and contraction of components should yield better fits and less rubbing as well.. Not being a motor-head I don't know if this will up the MPG... but it should change something.
I have no idea how the added space on the throttle body or intake manifold would affect anything.. but I guess I'm ignorant on that topic.
Buying your gas at different stations, getting oil changes, and changing your tire pressure all have a pretty serious correlation with gas mileage. I don't know why you'd think altering your engine's thermal / intake characteristics wouldn't.
IE- In theory all of this stuff SHOULD have done something.
In practice - not so much so apparently. So yes, you're right, but no that's not the popular opinion, nor is it backed up by anything.
-Rx
That's like saying the only way to gain horse-power is by decreasing weight and pressing harder on the gas.
I'm not saying you're wrong... Those are definitely two ways to increase mileage...
But...
Theoretically, air intakes should have an effect on your vehicles mileage. Changing the air / fuel mixture will alter the efficiency of the engine for better or worse.
The thermal spacers definitely (absolutely) work wonders for isolating temperature. My CAI was cold to the touch this morning (after driving 23 miles), as well as the throttle body. The plenum was probably about 85 degrees. As a comparison, when I went to do the mod I had to wait over an hour with the hood open just so I could touch the throttle body... Never mind the plenum. A HUGE temperature difference like this will absolutely change the characteristics of air-flow in the area... Cold air turning to warmer and warmer air (at least from the physics standpoint) will increase resistance as the volume expands. Decreased expansion and contraction of components should yield better fits and less rubbing as well.. Not being a motor-head I don't know if this will up the MPG... but it should change something.
I have no idea how the added space on the throttle body or intake manifold would affect anything.. but I guess I'm ignorant on that topic.
Buying your gas at different stations, getting oil changes, and changing your tire pressure all have a pretty serious correlation with gas mileage. I don't know why you'd think altering your engine's thermal / intake characteristics wouldn't.
IE- In theory all of this stuff SHOULD have done something.
In practice - not so much so apparently. So yes, you're right, but no that's not the popular opinion, nor is it backed up by anything.
-Rx
05-19-2008, 01:01 PM
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Your examples are theoretically correct, but as you've seen, there's a big difference between theory and reality. Lots of things look good on paper. Personally, I would never expect to see any improved mileage from an intake and spacers. And I don't know whose input the popular opinion was derived from, but I tend to take popular anything with a grain of salt.
On the other hand, if I dropped 100 pounds of weight from the car and accelerated slowly and never exceeded 65mph, I would expect to see an improvement...and that is backed up by lots of research (not done by companies trying to sell a product).
On the other hand, if I dropped 100 pounds of weight from the car and accelerated slowly and never exceeded 65mph, I would expect to see an improvement...and that is backed up by lots of research (not done by companies trying to sell a product).
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05-19-2008, 02:35 PM
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Yeah, I know... Which is why I was always confused by the CAI efficiency claims...
But technically, although the engine senses more air and injects slightly more fuel, it should still all be combusted if the air reading is correct. So, you should technically require less throttle... right? I mean, more air + more fuel = bigger explosion... Less air + same fuel = running rich. If you didn't correct for the new air flow you'd run lean and overheat the pistons.
It doesn't make your engine less efficient just because it uses more fuel per stroke. I mean... That's probably where the horse-power claims come from.
But technically, although the engine senses more air and injects slightly more fuel, it should still all be combusted if the air reading is correct. So, you should technically require less throttle... right? I mean, more air + more fuel = bigger explosion... Less air + same fuel = running rich. If you didn't correct for the new air flow you'd run lean and overheat the pistons.
It doesn't make your engine less efficient just because it uses more fuel per stroke. I mean... That's probably where the horse-power claims come from.
05-19-2008, 02:51 PM
#11
.:KCCO:.
its basic...
more air = more fuel (balance the mixture)
AND
cooler air = more fuel (it becomes more explosive and has potential for more power)
so the cai gives you cooler air and so do the spacers
i'll agree with you that you can give it less throttle now and get the same amount of power but then it still uses the same amount of air and gas pre-modinstallation
after the install was done, you are using more air and more fuel. how can one really expect better mpg.
it would be so miniscule, i doubt it would be measureable in whole numbers.
more air = more fuel (balance the mixture)
AND
cooler air = more fuel (it becomes more explosive and has potential for more power)
so the cai gives you cooler air and so do the spacers
i'll agree with you that you can give it less throttle now and get the same amount of power but then it still uses the same amount of air and gas pre-modinstallation
after the install was done, you are using more air and more fuel. how can one really expect better mpg.
it would be so miniscule, i doubt it would be measureable in whole numbers.
05-19-2008, 03:12 PM
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Yep, reset the ECU. Before I did it was running VERY rich...Seriously...
I didn't REALLY expect a huge mileage jump. I was just once again disappointed by the marketing and bandwagon-ing that I bought into.
As I said, I mainly just posted this so that others who used the search function would find some posts to the contrary. If you search, you'll see that almost all of the CAI posts claim a MPG increase of 1-2. Same with the outlaw engineering site "Better gas mileage".
PS: Anyone know if this is true? "A cooler intake charge also reduces the tendency for detonation, meaning ignition timing can be advanced for MORE POWER"
And if so... does that mean that we can use reduced octane fuel? (how much?) And or how do you change your ignition timing? (probably can't right?)
I didn't REALLY expect a huge mileage jump. I was just once again disappointed by the marketing and bandwagon-ing that I bought into.
As I said, I mainly just posted this so that others who used the search function would find some posts to the contrary. If you search, you'll see that almost all of the CAI posts claim a MPG increase of 1-2. Same with the outlaw engineering site "Better gas mileage".
PS: Anyone know if this is true? "A cooler intake charge also reduces the tendency for detonation, meaning ignition timing can be advanced for MORE POWER"
And if so... does that mean that we can use reduced octane fuel? (how much?) And or how do you change your ignition timing? (probably can't right?)
05-19-2008, 08:22 PM
#14
practicing nihilist
Originally Posted by RobxMcCarthy
PS: Anyone know if this is true? "A cooler intake charge also reduces the tendency for detonation, meaning ignition timing can be advanced for MORE POWER"
And if so... does that mean that we can use reduced octane fuel? (how much?) And or how do you change your ignition timing? (probably can't right?)
05-19-2008, 09:26 PM
#16
If you know you were running rich before the installs- what did you do to correct that problem?
Was it plugs? or a bad coil? what???? how many miles/year? original plugs?
If you can see the oil and carbonnish looking buildup on the TB butterfly plate (very easy to clean with either the CAI install or the manifold spacer install) then you need to seafoam, or wynns, or bg thru the gas tank and intake manifold thru the main vac port at the TB.
Most of what you see on the TB plate is from the emissions sysytem, routing valve area. vapors (there is oil in there) to the TB and into the engine to be reburned - that lowers hydrocabon emissions!
colder air is more condensed air, thats what makes better combustion- stuffing the cylinder full with more air density for its capacity, plus you are feeding the engine all its wants to draw in for airflow-- with a CAI, or just removed intake resonator box and a hi flow air filter of your choosing.
What makes it all tick:
The dual O-2 (oxygen= 02 get it?) sensors- 1 lives on each side of the cat convertor- tells the ECU what the engine is sending out down the exhaust pipe in the form of unburned fuel, and what it was able to do inside the cat for the final readings at the 2nd O2 sensor unit after the cat. Then the throttle position- gear in use- timing-coolant temp-various zillion other things... and the ECU "Engine CONTROL Unit" tells the adjustable things to modify their settings.
Sending less fuel when its rich at the cats, more fuel when the engine is dead cold in the morning, running full lean as possible on the freeway cruise...checking all the parameters several times per second and constantly correcting-
in MY Opinion- that merits keeping the internals clean, and running 91 octane of Tier1 Brands of gas- I use chevron or shell
By resetting the ECU with the CLOCK fuse pull trick, or disconnecting the battery neg, you force a reboot and let the system learn whats new.
It needs clean injectors, valves, and pistons to work at max efficiency. Clean them with your choice of products- then a few days later do an ecu reset
It can take 2 weeks of normal driving for the system to relearn everything, then when you do the crank pulley you need to reset again
The lighter weight pulley will make the car accellerate faster - and the underdrive ones will help freeway mileage when AC is running full time, when its 100 outside and your going 80,
the reduced rpm of the AC compressor is the mileage gain- less engine drag
You cant throw performance parts on and expect it to fix an existing problem!
I wish I got 30, must need to drive when there is no traffic- this car hates stop and go!
GO GO GO- oh it loves that!!
Was it plugs? or a bad coil? what???? how many miles/year? original plugs?
If you can see the oil and carbonnish looking buildup on the TB butterfly plate (very easy to clean with either the CAI install or the manifold spacer install) then you need to seafoam, or wynns, or bg thru the gas tank and intake manifold thru the main vac port at the TB.
Most of what you see on the TB plate is from the emissions sysytem, routing valve area. vapors (there is oil in there) to the TB and into the engine to be reburned - that lowers hydrocabon emissions!
colder air is more condensed air, thats what makes better combustion- stuffing the cylinder full with more air density for its capacity, plus you are feeding the engine all its wants to draw in for airflow-- with a CAI, or just removed intake resonator box and a hi flow air filter of your choosing.
What makes it all tick:
The dual O-2 (oxygen= 02 get it?) sensors- 1 lives on each side of the cat convertor- tells the ECU what the engine is sending out down the exhaust pipe in the form of unburned fuel, and what it was able to do inside the cat for the final readings at the 2nd O2 sensor unit after the cat. Then the throttle position- gear in use- timing-coolant temp-various zillion other things... and the ECU "Engine CONTROL Unit" tells the adjustable things to modify their settings.
Sending less fuel when its rich at the cats, more fuel when the engine is dead cold in the morning, running full lean as possible on the freeway cruise...checking all the parameters several times per second and constantly correcting-
in MY Opinion- that merits keeping the internals clean, and running 91 octane of Tier1 Brands of gas- I use chevron or shell
By resetting the ECU with the CLOCK fuse pull trick, or disconnecting the battery neg, you force a reboot and let the system learn whats new.
It needs clean injectors, valves, and pistons to work at max efficiency. Clean them with your choice of products- then a few days later do an ecu reset
It can take 2 weeks of normal driving for the system to relearn everything, then when you do the crank pulley you need to reset again
The lighter weight pulley will make the car accellerate faster - and the underdrive ones will help freeway mileage when AC is running full time, when its 100 outside and your going 80,
the reduced rpm of the AC compressor is the mileage gain- less engine drag
You cant throw performance parts on and expect it to fix an existing problem!
I wish I got 30, must need to drive when there is no traffic- this car hates stop and go!
GO GO GO- oh it loves that!!
05-19-2008, 10:00 PM
#17
Team Owner
CAI giving better mileage is a bad myth.
No matter what, it takes a certain amount of fuel to make a certain amount of power. Your AF is calculated by the computer and checked with the 02 sensor. It does not change.
For example you're cruising down the freeway on cruise control and the temperature drops 50 degrees. The engine makes more power at that throttle (requiring more fuel to maintain the mixture) opening so the computer closes the throttle some to maintain a given speed. If the throttle wasn't closed a little, mileage would get worse and the car would pick up speed.
No matter what, it takes a certain amount of fuel to make a certain amount of power. Your AF is calculated by the computer and checked with the 02 sensor. It does not change.
For example you're cruising down the freeway on cruise control and the temperature drops 50 degrees. The engine makes more power at that throttle (requiring more fuel to maintain the mixture) opening so the computer closes the throttle some to maintain a given speed. If the throttle wasn't closed a little, mileage would get worse and the car would pick up speed.
05-19-2008, 10:07 PM
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Thanks 01tl4tl, that was some good info.
I meant that when I first installed the CAI and spacers without doing an ECU reset the car ran very rich (before mods it was fine). I shut the car off, reset the computer and it ran fine again.
There was a tiny bit of buildup on the butterfly plate...I'll probably seafoam this weekend.
I drive at 7:00 and 5:00, but the traffic travels at a steady 45-70.. Occasional stop and go. It's 5 miles of backroad - 10 miles of highway and then 7 miles of 45 mph zone where traffic flows pretty freely.
On a straight highway run at 65 mph I get 36 MPG (according to the trip computer), which has been pretty consistent with the gas fillup check.
I meant that when I first installed the CAI and spacers without doing an ECU reset the car ran very rich (before mods it was fine). I shut the car off, reset the computer and it ran fine again.
There was a tiny bit of buildup on the butterfly plate...I'll probably seafoam this weekend.
I drive at 7:00 and 5:00, but the traffic travels at a steady 45-70.. Occasional stop and go. It's 5 miles of backroad - 10 miles of highway and then 7 miles of 45 mph zone where traffic flows pretty freely.
On a straight highway run at 65 mph I get 36 MPG (according to the trip computer), which has been pretty consistent with the gas fillup check.
05-19-2008, 10:14 PM
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Also: I hate cars had the most valid point. That sounds like it makes a lot of sense. But does the air temperature and availability have any effect on engine output efficiency?
05-19-2008, 10:20 PM
#20
yes
05-20-2008, 07:33 AM
#21
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I Hate Cars and 01tl4tl pretty much summed it up. There are SO many other variables with motors and electronics on cars now days. You really need to understand how a motor and its efficiency work and are related to under stand how any one of these mods would work. (not even going to try to explain, a class would be much better) While im sure there are some gains they are going to be minuscule.
05-20-2008, 09:57 AM
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Um... Yeah...
How's that one going to save me 5 mpg? If I was getting 35-38 avg (I doubt the people who install it are) then I'd practically be getting the same as some hybrids.
Just saying... This is the same garbage I fell for last time.
How's that one going to save me 5 mpg? If I was getting 35-38 avg (I doubt the people who install it are) then I'd practically be getting the same as some hybrids.
Just saying... This is the same garbage I fell for last time.
05-20-2008, 11:13 AM
#24
if you were/are getting 35-38 mpg in a TL!!!-
The first thing I would do... is take a handheld GPS unit for a ride, and run a speedo check of its instant readout versus the cars system.
Our cars are known to run 5% high reading speedo/ODOMETER, which means you are travelling less miles than it indicates- resulting in higher that reality mileage calculations
If you have changed tire/rim size that can account for a small error in reading as well.
I dont care what your MID says- I dont know if its measuring the actual fuel delievery to the injectors and calculating how much fuel is going back to the tank, or getting its mileage reading from the speedo, but it ~feels~ like its as accurate as the old school vac guage that has mpg and the vac reading markes as the mileage
15 inches vac= 15 mpg,,,or as I hope for 10 inches vac is 10 mpg, yeah maybe downhill without the camper behind us!!
what next- The midi tells you when to wash the car???
Whats the actual full tank get?- set odometer to zero- run down the tank- refill to same 1st click of pump- divide miles driven by actual fuel used (the amount you put back in to full)
thats what the real fuel useage numbers are.
On the truck I do it in Gallons Per Hour- just like in the airplane~ about 6 gallons per hour
My truck speedo reads more miles on a trip than the gps says we travelled, meaning I get even less economy that it seemed- and it was at terrible to start!!
The GPS confirms that speedo runs about 5-6 mph fast on the freeway, at least it helps avoid speeding tickets!!
The first thing I would do... is take a handheld GPS unit for a ride, and run a speedo check of its instant readout versus the cars system.
Our cars are known to run 5% high reading speedo/ODOMETER, which means you are travelling less miles than it indicates- resulting in higher that reality mileage calculations
If you have changed tire/rim size that can account for a small error in reading as well.
I dont care what your MID says- I dont know if its measuring the actual fuel delievery to the injectors and calculating how much fuel is going back to the tank, or getting its mileage reading from the speedo, but it ~feels~ like its as accurate as the old school vac guage that has mpg and the vac reading markes as the mileage
15 inches vac= 15 mpg,,,or as I hope for 10 inches vac is 10 mpg, yeah maybe downhill without the camper behind us!!
what next- The midi tells you when to wash the car???
Whats the actual full tank get?- set odometer to zero- run down the tank- refill to same 1st click of pump- divide miles driven by actual fuel used (the amount you put back in to full)
thats what the real fuel useage numbers are.
On the truck I do it in Gallons Per Hour- just like in the airplane~ about 6 gallons per hour
My truck speedo reads more miles on a trip than the gps says we travelled, meaning I get even less economy that it seemed- and it was at terrible to start!!
The GPS confirms that speedo runs about 5-6 mph fast on the freeway, at least it helps avoid speeding tickets!!
05-20-2008, 02:29 PM
#26
Your the first person that I've read about that was getting 30+ mph that took it upon themselves to try to get more. I know that gas prices are high, but what is the break even point for the roughly $300+ in parts you just put on?
I know its said time and time again, but it is soo true. If gas prices are THAT big of a problem then maybe a more modest car should be in your plans.
I fill my car up once a week. Gas cost me $48 from empty last August (per my mileage report for work), that same tank fill cost me $55. So the $7 extra per week, $392 a year. But those 1 or 2 mpg you were looking to get were not going to pay off for years to come by those standards. In my opinion the CAI is a noise box, it sounds good but didn't do anything noticibly good or bad.
So I'm not bustin your chops. :thumbs: Just saying that during this rough econimic time, people that able to afford this car by the slimest of margins 2 years ago might be in a tough place now because costs of fuel prices on the rise. If 30-33 mpg is not enough, you'll need to look for a smaller car. A vehicle of this caliper/size will not offer anything higher.
I know its said time and time again, but it is soo true. If gas prices are THAT big of a problem then maybe a more modest car should be in your plans.
I fill my car up once a week. Gas cost me $48 from empty last August (per my mileage report for work), that same tank fill cost me $55. So the $7 extra per week, $392 a year. But those 1 or 2 mpg you were looking to get were not going to pay off for years to come by those standards. In my opinion the CAI is a noise box, it sounds good but didn't do anything noticibly good or bad.
So I'm not bustin your chops. :thumbs: Just saying that during this rough econimic time, people that able to afford this car by the slimest of margins 2 years ago might be in a tough place now because costs of fuel prices on the rise. If 30-33 mpg is not enough, you'll need to look for a smaller car. A vehicle of this caliper/size will not offer anything higher.
05-20-2008, 03:29 PM
#27
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*shrug* Doesn't bother me that much. I mainly did the mods to get my hands dirty with the car.
Paid $150 for the intake and ~$100 for the spacers = $250
But, currently I drive approximately 18.5k miles per year: If I got only a 2 mpg bump (minimum of both advertisements) at only $4.00/g (going up)... Then...
[(18,500m / 30mpg) - (18,500m / 32mpg)) * $4] = $154 per year.
At $5 it's $192
With the avg bump suggested (1.5 + 1.5)= 3 mpg gain
[(18,500m / 30mpg) - (18,500m / 33mpg)) * $4] = $224 per year.
At $5 it's $280
I haven't done the under drive pulley yet... But that was another 1-2 mpg.
Occasionally I'm known to be a rather spirited driver... So, these mods weren't entirely wallet/environmentally conscious; but you can see why I was a little disappointed. At the average suggested bump (marketing) the parts would be paid off in a year-ish. At least, that's how I justified buying them ;-).
I may have a plenum or throttle body leak... The gaskets weren't replaced and I didn't have a torque wrench. So, if re-sealing those bumps this up any I'll have to re-neg this whole post...How embarrassing would that be?
Paid $150 for the intake and ~$100 for the spacers = $250
But, currently I drive approximately 18.5k miles per year: If I got only a 2 mpg bump (minimum of both advertisements) at only $4.00/g (going up)... Then...
[(18,500m / 30mpg) - (18,500m / 32mpg)) * $4] = $154 per year.
At $5 it's $192
With the avg bump suggested (1.5 + 1.5)= 3 mpg gain
[(18,500m / 30mpg) - (18,500m / 33mpg)) * $4] = $224 per year.
At $5 it's $280
I haven't done the under drive pulley yet... But that was another 1-2 mpg.
Occasionally I'm known to be a rather spirited driver... So, these mods weren't entirely wallet/environmentally conscious; but you can see why I was a little disappointed. At the average suggested bump (marketing) the parts would be paid off in a year-ish. At least, that's how I justified buying them ;-).
I may have a plenum or throttle body leak... The gaskets weren't replaced and I didn't have a torque wrench. So, if re-sealing those bumps this up any I'll have to re-neg this whole post...How embarrassing would that be?
05-20-2008, 04:05 PM
#28
your kidding us right??
- you installed an intake spacer,,,, and TB spacer,,,,- took off the intake manifold assembly completely- removed it from the car, and into your hands, and onto the workbench,,, and you saw the metal base gasket- thats cool to reuse- but the others you left alone- the ones that have their remains stuck on in bits and pieces that must be carefully scraped off the surfaces perfectly smooth and flat,,,,
and then put it all back together,,,
Didnt the new spacers come with their own gaskets???
So it went back together without new gaskets, and without a torque wrench,,, and the car makes a whistle like an air leak and doesnt get the mileage gain you had hoped for?!?!?!?!!?!?
Is that the correct interpretation of the story? correct me I if got this wrong
Now let me try to look surprised
Nope- not working~
I would look first at the very top cover of the intake manifold- its possible to remove its gasket and it gets flipped over- it appers to fit- but the inner parts of the gasket are covering something important. Several ziners have found by pulling that cover and make sure the gaset is lined up with all the correct holes on the engine side, not the covers side- it will fool you
- you installed an intake spacer,,,, and TB spacer,,,,- took off the intake manifold assembly completely- removed it from the car, and into your hands, and onto the workbench,,, and you saw the metal base gasket- thats cool to reuse- but the others you left alone- the ones that have their remains stuck on in bits and pieces that must be carefully scraped off the surfaces perfectly smooth and flat,,,,
and then put it all back together,,,
Didnt the new spacers come with their own gaskets???
So it went back together without new gaskets, and without a torque wrench,,, and the car makes a whistle like an air leak and doesnt get the mileage gain you had hoped for?!?!?!?!!?!?
Is that the correct interpretation of the story? correct me I if got this wrong
Now let me try to look surprised
Nope- not working~
I would look first at the very top cover of the intake manifold- its possible to remove its gasket and it gets flipped over- it appers to fit- but the inner parts of the gasket are covering something important. Several ziners have found by pulling that cover and make sure the gaset is lined up with all the correct holes on the engine side, not the covers side- it will fool you
05-20-2008, 04:10 PM
#29
Team Owner
To take this a step farther, theoretically you will get better mileage with a hotter charge air temp.
To throw a curve, there's the possibility the computer will see the colder air and advance timing, giving you better economy. This is probably not the case with our TLs since they run on the verge (or past) of detonation anyway.
As far as restrictions, keep in mind the throttlebody is what controls airflow from idle to WOT. Unless you have a huge restricion in the intake tract, any gains from opening up the intake tract will be seen at larger throttle openings and higher rpms. You have the potential to flow more air at WOT with the CAI so you have to potential to use more fuel if you drive it hard all the time.
Exhaust is entirely different. Less exhaust backpressure means more power and economy. Where with the intake, if it has a restriction (the throttlebody), it will just make less power. With exhaust, if the piston can push the burned air/fuel mixture out easier, you pick up power and fuel economy. I suspect if you delete all 3 cats and install a J-pipe and full exhaust, 4-5mpg is not out of the question.
To throw a curve, there's the possibility the computer will see the colder air and advance timing, giving you better economy. This is probably not the case with our TLs since they run on the verge (or past) of detonation anyway.
As far as restrictions, keep in mind the throttlebody is what controls airflow from idle to WOT. Unless you have a huge restricion in the intake tract, any gains from opening up the intake tract will be seen at larger throttle openings and higher rpms. You have the potential to flow more air at WOT with the CAI so you have to potential to use more fuel if you drive it hard all the time.
Exhaust is entirely different. Less exhaust backpressure means more power and economy. Where with the intake, if it has a restriction (the throttlebody), it will just make less power. With exhaust, if the piston can push the burned air/fuel mixture out easier, you pick up power and fuel economy. I suspect if you delete all 3 cats and install a J-pipe and full exhaust, 4-5mpg is not out of the question.
05-20-2008, 04:35 PM
#30
Suzuka Master
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^^You're probably right on the 4-5mpg, but damn it'd take a long time to re-coup the 2 grand in fuel savings.
Not to mention nobody will have the willpower to take it easy on the throttle with that set-up!
Not to mention nobody will have the willpower to take it easy on the throttle with that set-up!
05-21-2008, 01:59 AM
#31
.:KCCO:.
Originally Posted by stillhere153
if you expect a drastic savings of up to like lets say 5mpg... get richie's test pipes...
05-21-2008, 06:29 AM
#32
05-21-2008, 07:16 AM
#33
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I did use the new gaskets where applicable.
I only got one with the throttle body spacer, and one with the intake manifold spacer...
The gasket I'm concerned with is the gasket under the plenum cover. Leaks due to incorrect and uneven torque specs are more likely than corroded gasket issues. Yes, the one on the throttle body was stuck.. but it also appeared to be in perfect condition. I cleaned it off, applied a very small amount of silicon, the spacer, and then the second (new) gasket.
If I had two gaskets per part I would have done this "correctly". But that wasn't the case. The intake manifold spacer install was a bit rushed because there was some serious pollen out of trees. Didn't want to see my engine fill up with debris and whatnot.
When I have access to a garage with some decent lighting I'll take her apart again.
Didn't mean to sound like a dick in this post or start a rant, by the way. Seems like the way I came off.
I only got one with the throttle body spacer, and one with the intake manifold spacer...
The gasket I'm concerned with is the gasket under the plenum cover. Leaks due to incorrect and uneven torque specs are more likely than corroded gasket issues. Yes, the one on the throttle body was stuck.. but it also appeared to be in perfect condition. I cleaned it off, applied a very small amount of silicon, the spacer, and then the second (new) gasket.
If I had two gaskets per part I would have done this "correctly". But that wasn't the case. The intake manifold spacer install was a bit rushed because there was some serious pollen out of trees. Didn't want to see my engine fill up with debris and whatnot.
When I have access to a garage with some decent lighting I'll take her apart again.
Didn't mean to sound like a dick in this post or start a rant, by the way. Seems like the way I came off.
05-21-2008, 12:14 PM
#34
I still think that topmost gasket- directly under the upper cover is flipped
when you say silicone you do mean real gasket stuff with hi temp features?
when you say silicone you do mean real gasket stuff with hi temp features?
05-21-2008, 09:59 PM
#35
Well my car from day 1 to 6 months of ownership would never break 30 mpg. At the 6 month point, I put in the CAI and now get 32-33mpg. This pretty much equates to delaying my fill up by 1 day. So that in addition to the MID's readings, to me, prove the CAI did something for my car.
If you're getting 33 mpg right now.. that's pretty darn good taking infact our cars are rated at 28 mpg highway. I seriously question your car actually getting over 30 mpg stock for the reasons already posted.
If you're getting 33 mpg right now.. that's pretty darn good taking infact our cars are rated at 28 mpg highway. I seriously question your car actually getting over 30 mpg stock for the reasons already posted.
05-22-2008, 02:13 AM
#37
are these mileage figures coming off the mid-??
or by the time tested method of fill the tank to 1st shutoff of nozzle-
drive it as usual till the fuel light comes on with 3 gallons remaining
Fill the tank to the 1st shutoff of the nozzle
To be as accurate as possible= go at same time of day- ambient temp, and use the same pump.
Divide miles driven by gallons used and replaced in fillup
example: 350 divided by 14 gallons= 25 mpg, 420 miles- 14 gallons - 30 mpg
How far do you guys go on a tank anyway!?
or by the time tested method of fill the tank to 1st shutoff of nozzle-
drive it as usual till the fuel light comes on with 3 gallons remaining
Fill the tank to the 1st shutoff of the nozzle
To be as accurate as possible= go at same time of day- ambient temp, and use the same pump.
Divide miles driven by gallons used and replaced in fillup
example: 350 divided by 14 gallons= 25 mpg, 420 miles- 14 gallons - 30 mpg
How far do you guys go on a tank anyway!?
05-22-2008, 01:59 PM
#38
Originally Posted by 01tl4tl
are these mileage figures coming off the mid-??
or by the time tested method of fill the tank to 1st shutoff of nozzle-
drive it as usual till the fuel light comes on with 3 gallons remaining
Fill the tank to the 1st shutoff of the nozzle
To be as accurate as possible= go at same time of day- ambient temp, and use the same pump.
Divide miles driven by gallons used and replaced in fillup
example: 350 divided by 14 gallons= 25 mpg, 420 miles- 14 gallons - 30 mpg
How far do you guys go on a tank anyway!?
or by the time tested method of fill the tank to 1st shutoff of nozzle-
drive it as usual till the fuel light comes on with 3 gallons remaining
Fill the tank to the 1st shutoff of the nozzle
To be as accurate as possible= go at same time of day- ambient temp, and use the same pump.
Divide miles driven by gallons used and replaced in fillup
example: 350 divided by 14 gallons= 25 mpg, 420 miles- 14 gallons - 30 mpg
How far do you guys go on a tank anyway!?
05-22-2008, 06:38 PM
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Originally Posted by RobxMcCarthy
Um... What is that theory based on?
That's like saying the only way to gain horse-power is by decreasing weight and pressing harder on the gas.
I'm not saying you're wrong... Those are definitely two ways to increase mileage...
But...
Theoretically, air intakes should have an effect on your vehicles mileage. Changing the air / fuel mixture will alter the efficiency of the engine for better or worse.
The thermal spacers definitely (absolutely) work wonders for isolating temperature. My CAI was cold to the touch this morning (after driving 23 miles), as well as the throttle body. The plenum was probably about 85 degrees. As a comparison, when I went to do the mod I had to wait over an hour with the hood open just so I could touch the throttle body... Never mind the plenum. A HUGE temperature difference like this will absolutely change the characteristics of air-flow in the area... Cold air turning to warmer and warmer air (at least from the physics standpoint) will increase resistance as the volume expands. Decreased expansion and contraction of components should yield better fits and less rubbing as well.. Not being a motor-head I don't know if this will up the MPG... but it should change something.
I have no idea how the added space on the throttle body or intake manifold would affect anything.. but I guess I'm ignorant on that topic.
Buying your gas at different stations, getting oil changes, and changing your tire pressure all have a pretty serious correlation with gas mileage. I don't know why you'd think altering your engine's thermal / intake characteristics wouldn't.
IE- In theory all of this stuff SHOULD have done something.
In practice - not so much so apparently. So yes, you're right, but no that's not the popular opinion, nor is it backed up by anything.
-Rx
That's like saying the only way to gain horse-power is by decreasing weight and pressing harder on the gas.
I'm not saying you're wrong... Those are definitely two ways to increase mileage...
But...
Theoretically, air intakes should have an effect on your vehicles mileage. Changing the air / fuel mixture will alter the efficiency of the engine for better or worse.
The thermal spacers definitely (absolutely) work wonders for isolating temperature. My CAI was cold to the touch this morning (after driving 23 miles), as well as the throttle body. The plenum was probably about 85 degrees. As a comparison, when I went to do the mod I had to wait over an hour with the hood open just so I could touch the throttle body... Never mind the plenum. A HUGE temperature difference like this will absolutely change the characteristics of air-flow in the area... Cold air turning to warmer and warmer air (at least from the physics standpoint) will increase resistance as the volume expands. Decreased expansion and contraction of components should yield better fits and less rubbing as well.. Not being a motor-head I don't know if this will up the MPG... but it should change something.
I have no idea how the added space on the throttle body or intake manifold would affect anything.. but I guess I'm ignorant on that topic.
Buying your gas at different stations, getting oil changes, and changing your tire pressure all have a pretty serious correlation with gas mileage. I don't know why you'd think altering your engine's thermal / intake characteristics wouldn't.
IE- In theory all of this stuff SHOULD have done something.
In practice - not so much so apparently. So yes, you're right, but no that's not the popular opinion, nor is it backed up by anything.
-Rx
CAI = more air, more air = more fuel, more fuel = less MPG.
and yes, less weight gives better MPG cause your engine isnt working as hard.
just like how if you are really fat your car hates you cause it has to push harder like its towing a load, which uses more gas cause you push on the throttle more.
anyone who even asks or thinks that a CAI is suspose to give better MPG is, well..has no common sence or knowledge of engines. when an engine sences[sp?] more air it automatically gives more fuel so you dont run lean.
05-22-2008, 06:51 PM
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full synthetic oil probably gives more MPG, especially an expencive one like royal purple- but then the amount you save in gas just pays for the oil, so you could go with mobile1 which is cheaper but supposidly doesnt give as much hp increase.