Need some J wisdom here. I realize there are posts about this but they always seem to go WAY off topic and everyone is already way past my level of modifications. So.....

I have a base model 08 TL 5AT. So far I've kept the mods light. I have a good cold air intake, I did the coolant bypass, added a manually adjustable fan thermostat (traffic in my area is terrible and in the summer I wanted more cooling), put the car on a diet of roughly 140 lbs, type s suspension stuff and I have a very good flashpro tune. Now I can't go WOT everywhere in my area so I was looking to boost the low to mid range torque. I also live where there are a sh*t load of hills.

I'm looking at a 3.5 manifold from an 09 TL for a decent price, an MDX manifold with MDX TB for a good price or simply the MDX spacer (found one for $60). I know the spacer MIGHT not fit but I have resources for that option. But if I wanted good passing power on the highway and a little more grunt in traffic what should I go with. Opinions?

I don't care AS MUCH about top end as mid to low end but I don't want to choke it too much. I will have the car re-tuned after the mod is complete. AT BEST I will eventually do a good exhaust system but right now I need the twisties. Car is paid off and runs like a champ so I won't buy anything else.

 

I'd suggest a new J-Pipe first, almost 15WHP+ gains in the mid range on the 3G TL, and with a tune it'll be even better.

The MDX spacer may have to be milled to fit, it lowers the curves in the RPM range but might choke up the top end.

Look into deleting the cats, I know you loose some low end power when you get rid of all 3. Getting rid of the 3rd one is the easiest (esp if you go with a long J-pipe). The pre-cat's are a bit harder to swap and you can do the deletes which loose low end power but gain power up top a bit, or you can do high-flow pre-cats which are the best of both worlds.

Good tires are a great bet too, if you can't put the power down effectively it doesn't matter. The same goes with the front compliance bushings, transmission mounts and motor mounts.

Also get a rear-sway bar, it'll help out on the twisty roads a bit! Lastly, have you looked into lightweight wheels?

 

Definitely look into a J-Pipe for better low to midrange power. Shoot me a PM for a couple options exhaust wise.

 

check it, nismo.

our cars make PEAK hp and PEAK tq at like 6000 RPM.
this is a characteristic of the engine and you cannot change this fact.

with this being said, any mods you do will increase top speed! because, that's how our engine is designed.

give yourself a little credit, because you are pretty modded. you've modded the car to your needs. however, I dont think these mods helped your need for more low end grunt.

so, you're asking for more!

a Jpipe, like the gentlemen above me suggested is great mod! however, dont be disappointed when the engine makes PEAK power in vtec range(4700-7000RPM).

side note; the reason why I like manuals with honda engines is because I can pick and choose when to be in the power range at ALL times.

 

Thanks for all the replies. Appreciate the wisdom. So I should lay off the intake then, huh? OK. I'll look into a J pipe then for starters. Honestly I've been eyeing up the CT engineering SC but the money has me rethinking it. I think Im more afraid of losing low to mid range power than gaining any really. That why I didn't do an exhaust yet.

And yes I need a manual! I came from a 07 Si so I am very familiar with Honda engines but this is my first 6 banger. There aren't many manual TLs around here without a ton of miles on them or a ton of dings and dents. That why I went with the auto in the long run on my 08. Great shape and low miles, plus the split spoke wheels had me sold.

For the J pipe, does this replace any cats? I need to keep those b****es on there because they are strict about inspection/emissions laws where I live. Even visual (I failed once for having a gutted cat on my truck).

What can I expect to feel with the J pipe and an upgrade on my tune? Like stock acceleration until VTec then a nice kick? Speaking of VTec, any thoughts on increasing it to 5K to smooth it out? Yes? No?

Side note: The diet helped this car a good bit but I kept most of the Luxo items. Between that and the tune I think I saw the biggest difference. Having moderate low end won't kill me. I spend more time on the highway now so I guess I'll focus on the mid to high RPM. I was considering trading in for newer but then one day I tried passing a 09-10 335ix and the guy punched it, so naturally I did too and even tho I couldn't get em, he couldn't pull away from me either. The stock BMW didn't out handle me in traffic either, now keep in mind I got Type S struts/springs and S Type sway bars (and a weight redux). But still he had a lot more torque and AWD. So for 15K and around 2K worth of mods I think I'm sticking with it.

 

Where are you located that they're so strict with the cats? They're high on the list of mods to really open the car up. You'll gain power everywhere with high flow or PCDs, not just top end.

I have full bolt ons, and the three most effective (not necessarily in order of effectiveness) were RV-6 high flow cats, TL-SHAWD manifold/ZDX TB/ported lower runners/ 4" Airaid CAI and Flashpro. I did them in that order after already having AEM intake, pulley, J pipe and cat back and the car just kept getting quicker. I honestly think the manifold/TB/runners/intake (just makes sense to group them all together) may have made the most difference above 5k; the car pulls strongly to 7100, even though power does start to level off after 6k. Shopping for cams now, since I want power to keep increasing up to 7k.

 

The J pipe will give you 4-5 whp and you won't feel it at all... Just delete the 3rd cat for the same gain and lower cost. A complete dual exaust would give gains that you will actually feel. Just search my dyno threads I have tried a lot of same day before and after comparaison tests, from j pipe test to aem v2 vs stock to zdx tb vs stock flashpro tune vs stock etc...

 

anx1300c: I live in Pittsburgh PA and in my county they not only plug your car into a computer for emissions but they also put it up on a rack and make sure everything is intact and accounted for (at least that's what happened to me each time). Twice I've failed because I had a test pipe or gutted cat even though I had no CEL and the sensors where all working correctly. $65 pass or fail. It sucks!


Did you notice any difference with the pulley? Was there any loss down low with the manifold, TB and runners? Thanks.


DomGSR-T: Thanks for the feedback. I've seen mixed responses on the J Pipe. Some love it and some don't. I'll check out your dyno threads today about exhaust. Thanks.

 

I love my jpipe ONLY because I utilize it to its full potential.

I live in vtec (4000-7000RPM)
and that's where the jpipe really shines.

sure, the jpipe will give you some horsies at 1200-2000 RPM, but its not like "OH SHIT, THE TORQUE!!"

no, its more like....OooO the TL is a little easier to drive at 2000 RPM.

again, where it really shines is up high

 

State inspectors will focus more on a modify car than a stock car.

 

Look at the P2R intake manifold spacer. It's similar to what is used in the Honda /Acura SUV's to make more low range TQ.

 

I was looking at the P2R intake manifold spacer. Anyone do this?


I might just do it. See what happens. Looks easy enough to install and if I don't like it I can just pull it back off. I was thinking the MDX spacer would be better but I don't want to mess with cutting it down. Besides by the time you do that you basically got the same thing as the P2R, right?


The only thing that keeps me pacified with the AT is the manu-matic function. I can say from experience its not bad, not a real manual but not bad. I test drove a Legacy GT with a sloppy manu-matic auto and then my wife had an A4 which ate it's trans at 58K (probably because of me beating on it but shhhh!) My wife's newer Accord only has D and D3 which sucks so there's that too.

 

no, the mdx spacer is an inch bigger.
which provides more volume in the intake manifold.

an easier way to make the MDX spacer fit, is to cut a little bit of the hood bracing.


there are dyno's out there, the MDX spacer shows a gain of roughly about 5 hp just before vtec.

not sure if you will feel 5 hp in a 3500lb car.

 

You're right, you won't feel 5hp but if I can reach my torque lower in the rpms I won't have to keep the revs as high (which means less manual shifting). Not that there is anything wrong with that! If I had a manual trans I wouldn't even consider this spacer and just go for the top end. I'm actually anxious to see what a re tune would do with this spacer. I bet you can squeeze a little something more with it. Even if its just 1ftlb or 1hp.

 

try!

as said before, cut the hood bracing away, instead of milling the MDX spacer.

 

Good options! I'm on the same boat with you nismo, low mileage 5AT. All this talk is making me want that j-pipe again even though my ride is bone stock and I have no choice but to drive to work everyday through stop & go traffic (my work is nowhere near a highway). Methinks that j-pipe will help with lower rpm range speed...

 

Buy a P2R spacer, it's shorter and doesn't require any mods to fit. I'm running it and it fits great. I can't comment on the power since I'm turbo. Makes it much easier to run aftermarket fuel rails and return fuel system.

 

^but since its shorter, less gains.
its like less than an inch.

might as well not have one in there?

 

You might be right it's 3/4 of an inch.

 

makes ton of sense for you and your aftermarket fuel rails and ease of access.....

 

Honestly, it will be insignificant comparing the 2 (P2R vs MDX) power wise. Its not like the extra 1-2 hp/tq will make a difference. P2R for clearance or MDX for an extra 1-2 power. Take a pick.

 

talking about splitting hairs.

 

Since you guys are lost on the gain the mdx spacer gives... and that I have tried a milled 1'' mdx spacer (no getto hood thing for me so the hood closes perfect without modification) on a 30 minutes before and after test... (time it took to put in on the car while the car was still strap to the dyno)

I gained:
4 WTQ at 2000
7 WTQ at 2500
7 WTQ at 3000
8 WTQ at 3500
12 WTQ peak gain at 4300
6 WTQ at 5000
7 WTQ at 5500
4 WTQ at 6000
2 WTQ at 6500

This is by far the best mods I did for the money.

 

If I knew I could make the MDX spacer fit I'd do it but I can't shim or cut my hood. I mean I CAN but I won't like it. Once I get the spacer on there I'll post my comments on it. Before and after the retune. Since I'm almost stock in the engine department it will be a pretty good comparison I think. It looks like most of the people who have added this have exhaust systems, boost and manifold modifications like porting and all that.


Thanks again for the input guys.

 

Thanks DomGSR-T.


Even if the P2R spacer gave me 75% of that gain I'd be happy (since its 3/4 of an inch and not 1 inch).
Speaking of inches (insert inappropriate joke here), the spacer does come with 2 of those thermal blah-blah whatever gaskets. They look pretty thick. That might make it a full inch, or close to it.


Did any HP drop off at all in the higher RPMs? I've read that's a possibility with the MDX spacer. If you don't mind me asking, what other mods did you have on your car at the time?

 

Can you clear your inbox? And I did not lose power at top but maybe full mdx spacer would but no way to tell since no one tried it as a same day test...

 

Done. New member so I only get space for two messages.

Thank you for the input.

 

Just get the MDX one milled, I bought one a while ago and it's sitting in a box somewhere. It was like $30 to have it milled. If it's something you really want I don't mind getting 2 done and sending you one if you split it with me.

The P2R spacer is good for 2 reasons but won't make power the same way the MDX spacer works.

MDX spacer adds more length to the runners and volume by a a fair bit. This is way more closer to the valves with higher velocity air rather than the slightly lower velocity air near the throttle body. Furthermore it spaces the intake manifold further away from the hot engine block. By doing this, the intake system heats the incoming air less. With better gaskets, it's reduced.

People used to use Outlaw gaskets that helped reduce the heat transfer from the block to the manifold. P2R makes similar ones for both the TB and the intake manifold.

P2R Intake spacer adds volume after the TB (about 1/2) and it doesn't help the velocity stack effect like the MDX spacer. It separates the intake manifold and TB helping reduce heat soak/heat loss. (There is also a coolant line that runs through the TB, I'd recommend removing it until icy weather comes so the TB doesn't freeze)

For the money, I honestly suggest the MDX manifold spacer with both sides having the P2R/Outlaw gaskets. You'll actually make more power and being more efficient rather than making power you would have otherwise lost.

Also forgot to mention some folks reported an MPG gain with a new J-pipe installed on the MDX, 3G TL and 4G TL.

 

P2R makes a spacer that fits between the lower runners and the upper manifold just like the MDX spacer only its already "milled" (or cut to size) to fit the Acura TL/Accord V6. That's what we (or at least I) was talking about. I wouldn't spend money on a TB spacer (no offense to anyone here).

 

That's the spacer I'm talking about as well, the manifold spacer.

 

I had no clue that existed! Sweet! Screw the one I have then, in the box it stays.

 

Spacer should be here Friday. [Taps fingers together like Mr. Burns] Eeeexellent! I'll install Saturday and give my feedback before I retune.

 

So I got thespacer on yesterday but didn't get a change to try it out until thismorning. The install took me ~3 hours but here is why....

(Pictures willfollow once I'm at home on my PC)

I pulled theintake manifold off and immediately saw a good bit of carbon and crud in themanifold and runners. I also saw a few wires and tubes that neededextended so I went to the local auto parts store and picked up some throttlebody cleaner and tubing. I moved a few wiring harnesses around to getsome more slack then I removed the intake manifold.

The removal waseasy. All I had to do was disconnect the TB wire harness, all theconnectors for the sensors and vtec motor, 4 vacuum lines and then unbolt themanifold.

I used 3 cansof throttle body cleaner to spray out the entire manifold and TB. Then I used the rest to spray some paper towels, then carefully cleanedthe inside of the lower runners. This was probably the most timeconsuming part. The manifold is spotless now but I could have used somemore TB cleaner for the lower ports. Still they are better than they werebefore.

Installationwas a bit of a pain. On the stock set up you have 2 bolts on the lowerrunners which are threaded at each end allowing you to easily line up themanifold. The P2R bolts were just longer bolts. So I had to placethe spacer and gaskets as evenly as I could on the lower runners and then sticka couple of the new bolts through the manifold and carefully slide them intothe spacer and gasket bolt holes. It took me forever to do this becausethe gaskets, spacer and manifold had to be perfectly aligned. Once I gotit all lined up I finger tightened the bolts at first and then torqued them to18ft/pounds (going back and forth across the manifold like how you wouldtighten lug nuts, starting in the middle/top). The specs I found online said16ft/pounds but with the additional gasket and spacer I thought a little morewould be needed. I replaced 2 of the vacuum lines with longer tubing,connected the harness and all the connectors back up, making a few adjustmentsas I went. Then I had to pull the driver’s side wheel and move my CAIaround so it would reach the TB.

I was able toclose the hood with no problems. Car started up with a little sputter,most likely from the TB cleaner. No CELs. I pulled it out of thegarage, let it warm up and gave it a couple of light revs to clean out anyleftover carbon and cleaner. Idle speed was smooth and wasn’t any higherthan stock. No hesitation. Then I put her back in the garage and reflashedmy original tune with my Flashpro.
Now thismorning......WOW! I drove in slow moving stop and go traffic atfirst. Car felt lighter. Throttle response was slightlyimproved. Then I got on the highway and here is where it reallyshined. I drive ~80 mph on the highway each morning and the car did thiswith ease this morning. I noticed less downshifting to pass andaccelerate. When you put your foot lightly into it, the car would justpull with no downshift. When you got your foot into it hard it woulddownshift and take off. Not like muscle car take off but like a bigger V6would. I didn't get a WOT pull in because of traffic but I'm going to tryon my way home.

I had driven mywife's car all weekend and I figure it was the best benchmark for thismodification. Her car is a 2008 Accord3.5 V6 with slightly less miles on it. By comparison my Acura feels very close to her Accord.

* I didn't takeit to red line yet.

off idle to 2K –Accord has a little more grunt but the Acura very is close now.

2K to4K - Car pulls just like my wife’s Accord.

4K andup - Acura feels like it pulls a harder than my wife'sAccord.

Her car hasslightly more pull below 2K but beyond that it’s comparable until 4K. Thedifference is the top end is a little better on the Acura so I feel the HPdidn't suffer.

This is thebest modification I’ve done so far. I’manxious to try and adjust the tuning and see if I can’t improve it evenmore. I highly recommend this for allthe N/A guys.

 

do you know if the spacer milled, or was it full width? also the original mdx spacer thread had some nice step by step pics but the were linked to a photobucket page that isn't displaying the pics anymore. if you have some to share send me a PM please. congrats on the install.

 

Thanks!


The P2R spacer is machined from a solid piece of aluminum with similar specs to the MDX spacer but thinner. Its 3/4 of an inch thick and with the P2R thermal gaskets its a solid inch thick. Lines up nicely with the runners.


Working on getting pics. I'll put a step by step together as soon as I can and post as many pics as I can. I might have to make a diagram of the actual install.


In the meantime here is what you'll need:


* P2R spacer, 2 thermal gaskets and hardware (usually you can get the entire kit on Ebay or directly from P2Rs website ~$175).
* lots of paper towels
* a soft wire brush (like a brass brush)
* 10, 12 and 13 mm sockets
* A ratchet
* A torque wrench that will work with your sockets (I have a 1/4" drive one)
* A foot long piece of vacuum hose (I'll post the size/part number soon)
* Screwdriver to remove intake hose
* 3 cans of Throttle Body Cleaner (carb cleaner might be too harsh for the sensors)


Optional:
* Vacuum hose removal tool or pliers with soft (or no) teeth




You can also do the TB coolant bypass mod while you have the TB off (if you haven't already).


More to come.....

 

congrats on the install!

this is generally a good mod to do but not for all cars. i remember reading a few times that this mod is NOT recommended if you have PnP'd runners and intake manifold. I think there was a dyno with that setup and power was lost once the intake manifold spacer was added.

so yes it's a good mod, but it's not for everyone and people have to research their exact setup before going that route.

 

Correct. Thanks for adding that info. Otherwise this becomes nothing more than a "speed bump" between the manifold and runners. You COULD always PNP the spacer but that might not be worth the extra cost, IDK.

 

thanks for the parts list. I have a milled MDX spacer with the longer bolts sitting in a box for a while now, just no time to install. I plan on doing the coolant bypass along with the IM spacer. Plus I have a TB spacer as well, so while I'm in there I'd like to do all three. Looking forward to your write-up.

 

4 things to note here. Number 1, this is for a 2007 and 2008 Acura TL base. Number 2, you’ll see things still connectedthat I say needs disconnected….Lets just say I saw ways to speed up the processand make it easier during the install so I’m noting them here in thesteps. Hindsight 20/20. Number 3, my pictures are crap. Yes I reused some of them. My camera sucks and I didn’t take enoughpictures, so I apologize for that. Myphone would have been better but, you know, hindsight 20/20. Number 4, if you can find someone to help outit will go much quicker on the install.

• Disconnect intake tube and all 4 vacuum linespictured (yellow). Also disconnect allsensor connectors including the TB wire harness and the harness for the vtecsecondary intake valve on the passenger’s side (all in red).
• Unbolt purge solenoid from driver’s side of theintake. 10 mm.
  
• Unbolt throttle body (optional but it will makeinstallation easier).
• Remove top plate bolts and carefully pryup plate. Try to do a little section ata time around the corners. Be careful becausethe plate has the valve motor and secondary butterfly attached to it.
• There are 7 13mm bolts and 2 hex bolts that comewith the kit. The hex bolts replace thestuds used on the stock set up. I placedthese two hex bolts through the manifold where the studs once resided. I then lowered the manifold and guided then through the bolt holes inthe spacer and gaskets, getting them partially treaded into the lowerrunners. A real pain in the *ss but Ieventually got it. This is where you could use the help.
• I then got the remaining bolts started by handbut only about half way to allow wiggle room.
• I then hand tightened them all in this order:
• I then torqued them to 16ft/lbs in the sameorder. Then again at 18ft/lbs. I figure with the extra materials between themanifold and lower runners it could use a little more “snug”.
• I then used the rest of my Throttle Body cleanerto clean the top plate and butterfly, being careful to keep the cleaner awayfrom the motor for the butterfly valve.
• After the cover dried I installed and torquedthe bolts to 8ft/lbs in this order:
  
  
  
• I then reconnected the throttle body, reinstalled the purge solenoid, TBharness, vtec motor harness and all the sensor connectors. I had to replace the one vacuum line with alonger 7/32” vacuum line. Advance Auto partnumber: 5192900.
  
• I then pulled the front wheel, repositioned myintake to reach the throttle body and then reconnected the tube to the throttlebody.
• Once verifying everything was tight andreconnected, I replaced my wheel, lowered the car and started it. I pulled it out of the garage and let it warmup, giving it a couple of LIGHT revs to make sure all the cleaner got burnt offby the engine.
• Then I reinstalled my original tune viaFlashPro. If you don’t have a FlashProyou most likely want to reset the ECU by disconnecting the battery for ~15minutes.
• Took itout for a drive and I was very pleased with the results (see my prior post comparing this 3.2 to my wife's 3.5 Accord). Now I need to update my tune!

 

4 things to note here. Number 1, this is for a 2007 and 2008 Acura TL base. Number 2, you’ll see things still connectedthat I say needs disconnected….Lets just say I saw ways to speed up the processand make it easier during the install so I’m noting them here in thesteps. Hindsight 20/20. Number 3, my pictures are crap. Yes I reused some of them. My camera sucks and I didn’t take enoughpictures, so I apologize for that. Myphone would have been better but, you know, hindsight 20/20. Number 4, if you can find someone to help outit will go much quicker on the install.

• Disconnect intake tube and all 4 vacuum linespictured (yellow). Also disconnect allsensor connectors including the TB wire harness and the harness for the vtecsecondary intake valve on the passenger’s side (all in red).
• Unbolt purge solenoid from driver’s side of theintake. 10 mm.
  
• Unbolt throttle body (optional but it will makeinstallation easier).
• Remove top plate bolts and carefully pryup plate. Try to do a little section ata time around the corners. Be careful becausethe plate has the valve motor and secondary butterfly attached to it.
  
• Loosen all 7 bolts and 2 nuts on the manifoldthen gently rock it and pull it straight up. 13mm
  
  
• Remove the two remaining studs from the lowerrunners. No pic, sorry!
• I cleaned the lower intake runners but lightlyspraying them with throttle body cleaner and wiping them out with a papertowel.
• I then doused the intake manifold and throttlebody with throttle body cleaner. I usedalmost all 3 cans doing so. I then letit air dry before reinstalling.
• I then placed the gaskets and spacer on thelower runners. [stolen picture fromP2R] Picture shows the stock manifoldstuds on there. You can’t use themunfortunately. No bolts are placed inthe lower runners to hold the spacer and gaskets in place. You must set them down and line them upperfectly.
  
• There are 7 13mm bolts and 2 hex bolts that comewith the kit. The hex bolts replace thestuds used on the stock set up. I placedthese two hex bolts through the manifold where the studs once resided. I then lowered the manifold and guided then through the bolt holes inthe spacer and gaskets, getting them partially treaded into the lowerrunners. A real pain in the *ss but Ieventually got it. This is where you could use the help.
• I then got the remaining bolts started by handbut only about half way to allow wiggle room.
• I then hand tightened them all in this order:
• I then torqued them to 16ft/lbs in the sameorder. Then again at 18ft/lbs. I figure with the extra materials between themanifold and lower runners it could use a little more “snug”.
• I then used the rest of my Throttle Body cleanerto clean the top plate and butterfly, being careful to keep the cleaner awayfrom the motor for the butterfly valve.
• After the cover dried I installed and torquedthe bolts to 8ft/lbs in this order:
  
  
  
• I then reconnected the throttle body, reinstalled the purge solenoid, TBharness, vtec motor harness and all the sensor connectors. I had to replace the one vacuum line with alonger 7/32” vacuum line. Advance Auto partnumber: 5192900.
  
• I then pulled the front wheel, repositioned myintake to reach the throttle body and then reconnected the tube to the throttlebody.
• Once verifying everything was tight andreconnected, I replaced my wheel, lowered the car and started it. I pulled it out of the garage and let it warmup, giving it a couple of LIGHT revs to make sure all the cleaner got burnt offby the engine.
• Then I reinstalled my original tune viaFlashPro. If you don’t have a FlashProyou most likely want to reset the ECU by disconnecting the battery for ~15minutes.
• Took itout for a drive and I was very pleased with the results (see my prior post comparing this 3.2 to my wife's 3.5 Accord). Now I need to update my tune!