It may be that the torque increases outweight the upper end power and give a slightly negative slope on the torque curve. This could give the impression of not being as much power up top when in fact there is.

 

Sorry to get off the subject, but I am REALLY interested in how your auto performs with the supercharger. I have an '03 auto and was wondering if the $$ is worth it. My CL-S is all stock now. But if you can try to explain, in your opinion, the difference between before the supercharger and after the supercharger, that would be of great help to me. Was it a VERY noticable difference off the line and hammering it at 40 mph? I would hope it would be for that amount of money.

I'm just very curious, and I'm trying to decide which mods to do first, if any.

Thanks

 

i had a 3.5 cl-s and it wasnt an engine swap it used the mdx crank, rods, bearing, with dommed top pisons

 

I disconnected the IMRC and drove it this afternoon when temp was in the high 60's and the ping went away. I couldn't believe it. I have to drive it tonight when temp drop in the 50's. oh Scalbert did you have your IMRC disconnected? Have anyone remove the IMRC blade in the manifold?.

 

I'll try and quote scalbert, "the SC makes your 3rd pull as hard as if it was in 2nd gear"
Is that close Steve?

 

Myself and others have been running with the IMRC disconnected since last summer. Brad dyno'd his car with it connected and disconnected with a minimal differences; both with slight gains and losses throughout.

Do not remove the plates as that would be the same as holding the IMRC actuator on. Unplugging the actuator keeps the plates closed.

 

Close enough...

 

there are many reasons why you ran that time. For one thing it was 90 freakin' degrees with humidity. what was your 60'? If the guy with the 6spd was runing a 15, then the track times were really poor that day due to weather. perfectly normal occurance. just go back when its like 60 degrees out, and practise launching, and you should be set!

goodluck

 

My time slips at 85-90 degrees 3.2 engine, headers,port intakes,ice box,denso iridium plugs and 5.5lbs psi pulley.

R/T .547
60' 2.332
330' 6.138
1/8 9.247
MPH 79.36
1000' 11.951
1/4 14.236
MPH 99.11

 

It's all in the 60ft times. Lower your 60ft time and your E/T will also decrease. You have alot of work done to that car. Its pulling alot of Horsepower to the front wheels so another idea might be get some drag radials mounted on your stock wheels. Also its cold out now, take the car to the track again. Drag radials will probably run you about 300 bucks tops. Take them to the drag drop them to about 17-20 pounds and watch those lower E/Ts! DO that and I bet you'll drop into the 13s easy! Wheelspin is the enemy!!!!!!!!!!

 

I am posting some pictures for SGmotoring.

New and old engines:


Old one:


New one:

 

I have 2 Hoosier A3S03 245/35/18 road race tires and 2 extra rims sitting in the garage. I though that will be my best way to stop wheel spin. I regret spending those extra cash on tires and rims because I don't go drag strip that often (only once). I just want my car to be fast with street tires that way I can shock those EVO VIII that come by.

 

hey...have any problems mounting the A/C& belt tensoiner ? :wink:

 

maybe your 3.5L isnt faster than a stock CLS with S/C but some of ours are

 

That is a contradiction, as a vehicle with a blower would not be stock.

However, please further define the statement. The supercharger provides, at a minimum, twice the gains of the displacement upgrade. Regardless of what a single car has run the average times would show that the SC provides better gains.

Put simply, the 3.5L upgrade provides about a 10% increase in displacement. At best, 10% power increase is the most you could hope to gain with this change alone. That is even a stretch since everything else is/was designed for the 3.2L displacement.

The blower, with 6 PSI boost with the HBP, gives an effective displacement 4.5L which is a 40% increase. Even accounting for temperature increase, you could figure at least 30% increase in power and this is what it delivers.

 

 

i think what we're saying is a 3.5 with headers intake exhaust as he stated he drove, is according to him not as fast as an otherwise stock CLS with blower ...and again i say ...maybe his 3.5L ...

 

nice combo

 

if you figured it out mathematically what output should a 3.5L with 6PSI of S/C boost have? And if its only a 10% increase why is that upgrade so expensive?

 

Question for scalbert and other with supercharge and IMRC disconnected. Is it normal to have more boost with the IMRC diconnected? I never seen my boost guage read above 6 psi before or after the engine swap. Now that I disconnected the IMRC the same supercharge and pulley is boosting 6.5 psi but the engine is not pinging. I finally decided to do the swap because I was hoping to gain 20ft/lbs of torque and at a lower rpm (stroker kit). Swap is expensive because you are buying a complete short block, gaskets, hoses and etc.

 

did you have any issue re mounting your A/C and belt tensioner?

 

we all have to thank scalbert because i was pinging too with 94 octane and pulled the imrc plug a long time ago and never heard a ping again.mod addict gained hp through the low and mid point of the rpm band but lost just a little up top.there is no reason to have the imrc with a supercharged car.in a simple way the in stock form the imrc acts like a supercharger at 4800rpm the butterfly opens and allows a rush of air which gives you the effect of boost for that quick second.with a blown car its like having the imrc open all the time

 

I am sure it was making more power. But often it can be deceiving when being compared previous set ups. Plus, the torque curve can play interesting tricks on the perceived power output.

 

I would guess at around 35% - 40%.

It isn't that expensive relative to what is available. But the expense comes by way of large components needed. Namely the block, etc. But remember, the gains are throughout the power band; not at a single point so the total amount is nice.

 

Yes, it is perfectly normal and what we have witnessed.

Here is my take on why the knock is gone. The boost went up because the airflow ingested by the engine was reduced; there was more resistance to flow. What might have been occurring is that once the VTEC change over occurred there was an in rush of air lowering the boost and fuel pressure. But with more air entering and less fuel we went lean. Because more air was entering the motor the power potential was greater but was offset by the lean condition. With the IMRC disconnected there is lower airflow/more boost to keep the fuel pressure higher and keep it from going lean.

Just my hypothesis on the matter.

 

Doesn't the 3.5 conversion also raise compression about a point? I always assumed this is where the majority of the power increase was coming from. Would be good to see dynos of the 3.5 vs the blower. Lots of variables to 1/4 mile times.

 

you know i dont know...i always assumed that if you bolted typeS heads on a 3.5 shorty you would have the same compression ratio as the 3.5 had...but ive heard different so i dont know...mines 10.85:1

 

Without cc'ing the heads, it would be hard to know.

The parts #s for the 3.5-MDX heads (right/left bank) at the MDX PARTS LINK

are different than the CL-S part numbers (have to go to the selection page manually):

http://www.acuraautomotiveparts.net/...prddisplay.jsp

and enter Transmission/Engine Assembly from Pick list



A 3.5 Crank + 3.5 Rods + S pistons would be above 11.26:1

 

When Dean was discussing the kit on here he said that the 3.5 kit raises the compression to 10.8. Stock is 10.2? I don't know if that is correct or not. Seems the 3.5s of allmotor and typer are both very quick in the 1/4 mile but it seems they are also both very good at getting a car down the track. A big bump in compression would definitely yield a gain that was greater, proportionally, than the displacement increase.

 

Yes, Doug stated it was in the 10.85:1 range which is a bump from our stock 10.5:1. But this 0.35 CR increase would only account for about a 0.7% increase in power; negligible. A general rule of thumb is 2% power change for a single point in CR change.

Dean's 3.5L upgrade ends with a CR of 10.89:1 which is still only about a 0.8% change in power from the CR change alone. The majority of the gains are from the added cylinder volume.

 

allmotor_2000 is running the stock 3.2L.

 

I posted this earlier, and here is the "paste from the ealier post". BTW, I'd didn't count on the fate of the planet depending on every detail and assumption being "dead-on", but here it is:

"1. I believe the crank gets some chamfering to make for "better lubing" (as to SERIOUS work -- I don't think so).

2. The compression ratio is based on:

CV (cylinder volume) # the volume that is SWEPT by the top of the piston
CCV (combustion chamber volume) # the area above the piston at TDC (AKA unswept volume)

CR (compression ratio) = (CV + CCV) / CCV

3. The "slugs"/"pistons" are changed from the MDX to different pistons that allow for less compression (than with the MDX slugs) (Note: I can’t know for sure, since I haven’t seen the pistons, but I’ve included some math that will predict combustion chamber volume and compression ratio and the change in them (based on the pistons and wrist pins being identical). I’m making a guess, but based on the increase in compression with a 7mm increase in stroke, the compression would increase from 10:5 to 11.26.

4. IF the MDX pistons (at top dead center) LEFT the combustion chamber volume (as it was with a stock CL Type S), the compression would be increased due to the increase in stroke. The "swept" area is increased with the shorter rod (in the MDX) and longer stroke of the crank. If both sets of pistons were flat top pistons or the Type-S pistons were reused (if that was even possible) the change in compression ratio would be from 10:5 : 1 to 11.26 : 1.

Ok, first some specs:

< --------------------------- >
CL Type S
CL
Bore and Stroke: 3.50 in. x 3.39 in. (89 mm x 86 mm)

Type S compression ratio: 10.5: 1
CL compression ratio: 9.8: 1

Total displacement (just for checking purposes): 3210 CC 3.21 liters

< ------------------------- >
MDX
Bore and Stoke: 89 mm x 93 mm (That is a stroke that is 93-86 = 7mm longer in the 3.5L engine (MDX factory short block)
Total displacement (just for checking purposes): 3471 CC 3.471 liters
MDX compression ratio: 10:0: 1


Derived figures (see math below for equations to get the values):

MDX combustion chamber volume (CCV) = 64.22 CC (based on 10:1 compression ratio.



So, how about some math?


First, figure the “swept” volume (not including the combustion chamber volume:

(We just need the area of the bore x the length that the area is swept)

Pi r^2 = Area = Pi * (8.9cm/2)^2 = 62.21 cm

Volume = Area * stroke = 62.21cm^2 * 8.6cm = 535 cc (cm^3)

Now just to check, we take the 3210 CC that Acura gives for total displacement and divide by 6: 3210 / 6 = 535 cm^3 = 535 cc for each of the 6 cylinders in the V6.

Time for the combustion chamber volume (CCV): [ CV = chamber volume, and CR = compression ratio ]

CR = (CV + CCV) / CCV and CCV = CV/(CR – 1) [CR = 10.5, CV = 535cc (for stock 3.2L CS)]

CV = 535cc / 9.5 = 56.32cc (So, the combustion chamber volume is now found for a stock CLS

Now, let’s assume that the combustion chamber’s volume stayed the same with the MDX slugs (the volume removed or added at the top of the piston would have to subtract or add the same volume as the original CLS slugs did). (A flat top piston for both would make this a no-brainer).

The volume is now going to be greater with the stroke increased from 86mm to 93mm (+7mm).

Volume = 62.21 cm^2 * 9.3 cm = 578 cc. (This is the swept volume in an MDX or 3.5 type s)

Just to check 578cc * 6 = 3.468 liters (and is close enough to the 3.471 liter spec given in the Acura MDX website blurb)


Ok, I’ll assume that a miracle occurs and the MDX piston is designed to keep the combustion chamber volume exactly the same; this would allow for an increase in CR.

CR = (CV + CCV) / CCV = (578 + 56.32)/56.32 = 11.26 : 1 (With MDX pistons with same volume removed or subtracted from combustion chamber or if assuming both pistons are flat topped (they aren’t).

AND, lets check the math so far with the values I’ve obtained for a 3.2L CLS (no mods)

CR = (535 + 56.32)/56.32 = 10.5 : 1

If both sets of pistons were “perfectly” flat (flat top pistons), this would be done and one could assume that the stock block would give an increase in compression ratio from 10.5 : 1 to 11.26 : 1. (That’s assuming a bit, but it would be easy to see that it would be possible to have a compression ratio that is a bit to high for 91-octane and would probably move the requirement up to 93-octane. There’s probably a 2-percent gain there (5HP or so as well).

The pistons in $2500 conversion kit claims to have a compression of 10.85 :1. The combustion chamber volume would need to be reduced from a 3.2L engine (metal would need to be removed from the “slugs” when compared to the OEM 3.2L Type-S pistons (sitting at TDC). The change in volume to get the 10.85 would be CCV = CV / (CR-1). Solving for CCV we get: 578 / 10.85 – 1 = 58.68. The “new” pistons would have to “account” for a 58.68 – 56.32 = 2.36 cc increase in chamber volume (if the Type-s were flat top pistons, the pistons would have some small cut outs in the top.





Finally, if anyone wants to see if you can get some 0.050 oversize pistons, you can bore out the 3.2L to 3.3L and the 3.5L to 3.6+L …

As a note – with the shorter rod and longer crank, you are getting the piston speed to increase by around >10% and this causes the increase in lower and midrange torque/HP. The piston moves faster and gets the air moving quicker. The downside is the air speed at higher RPMS requires the heads to flow even more air – that’s one of the trade-offs…

The mean piston speed is also going to be greater at a given RPM. (This means there is more relative wear) Note: given the tranny situation, I wouldn’t worry about this AT ALL.)

Finally, a shorter rod doesn’t always mean more strength – it depends…


__________________
Silver 2001 CL-S with NAVI

 

No kidding? Damn. I thought for sure he had the 3.5. So his 13.50 was with a stock block and presumably stock ECU. That's f'ing incredible!!

 

Anyway to calculate torque? I like the characteristic of the 3.5L engine. Noticeable increase in torque form 1500 rpm and up. My car feel more torquey. Don't know if that is good for 1/4 mile? but sure is fun.

 

here you go...but you have to answer my question...any problems when putting the 3.5 in with the A/C and belt tensioner? oh and i've run 13.7 with my 3.5

http://www.tamparacing.com/forums/at...&postid=842780

 

not taking anything away,but this is the most modified 6mt NA with oversized throttle body,port /polished upper intake,16 slicks on probablly light weight wheels allmotor did you run the bogarts again? and the exhaust removed from the cat back? and ofcourse all the regular bolt ons...correct me if im wrong anybody and 13.5 is awesome ...were gonna start getting some respect soon

 

That's very impressive. I really want to track mine before I do any mods to the motor. I'm curious to see how the 60fts are with the motor mounts and radius rods filled with urethane. It definitely has a lot less slack in the drivetrain. 13sec 1/4 is great with no nitrus or turbo. Probably a lot left though with a good suspension setup and some ECU tweaking.

 

Chad, how are the motor mounts working out for every day driving?
As previously discuss, Ram ran open headers.

 

They're great. There is a bit of vibration at idle when the engine is cold. Also a bit at idle when the AC is on but it's not offensive at all. Once moving you can't really feel any additional vibration. Makes gear changes a lot smoother. When I first did it my wife even commented on how much smoother it felt. Doesn't make it easier to shift. There is just a lot less shock without the motor flopping around. I don't think you can do the motor mounts on an auto car but you could probably do the trans mounts which are a piece of cake to get out. I heard the video of Allmotors run. That sounds unreal with the exhaust off!!

 

No the A/C tensioner bolted right on.