I posted a while back about what exhasut the 3.4 guys were running on modified cars and did not get much of a responce, so I followed my gut and it payed off!

So the results are in...

What did the 2.5 inch mandrel bent y-pipe to a single 3inch mandrel bent exhaust system do for RAIF's performance (3.4l)????

Well some said it would kill the torque...
>>>WRONG!

Others said the exhaust system is too long from the start and a 3in would cause too much backpressure loss causing reversion & a lack of the proper scavaging effect...
(hence my old 2.25 crimp bent system initially gaining HP and torque when the cut out was opened. See an ideal system would see no difference with the cut out removed because it is flowing optimally!)
>>>WRONG AGAIN!

And others said is would sound like crap...
>>>WRONG! WRONG! WRONG!
(The car's sound impressed a VIPER guy with a 1000HP VIPER. Heck, the whole dyno shop thought I swapped in an V-8!)

Check out the gains yourself....




The graph is comparing my best pull with the cut out closed with the old crimp bent 2.25in system with the cut out closed!

Max Power = 141.3 @ rear wheels (+20%) = 169.56hp @ the fly wheel
Max Torque = 221.3 @ rear wheels (+20%) = 265.56ft-lbs @ the fly wheel

This puts me at 9hp over stock 3.4 numbers...
(Granted the 2.8 plenum probably is more restrictive then the 3.4's & my heads are 160,000 miles w/o a valve job!)
My torque is 65.56 over stock 3.4 numbers!

My gains with the 3inch exhaust over the 2.25...

Horsepower gains...15.4HP
Torque gains...18.2ft/lbs

And when the car was uncapped...I had instead 140hp and 222TQ...so esentially the same...meaning the system is very efficient!

Someone asked on another thread...I went from a 2.25 to a 3in how do I know what would have happened if I had gone with the 2.5 mandrel bend system?

Well I have PF&E headers and their mandrel bent y-pipe was 2.5...it flowed then to a 2.5 inch cut out. There was little restriction in this area (crimp bends)....So it was effectively a 2.5 inch system to the open cut out. I opened the cut out on a run not listed on the above dyno sheet...it is what gave the indication that I was in need of a better exhuast system.

I pulled on that run...
http://memimage.cardomain.net/member..._1004_full.jpg

134HP and 207 TQ At the wheels... so if I had only gone to a 2.5 inch system and it was as effective as the cut out, I would have flowed just that on a 2.5 inch system!

So my dyo differences from a 2.5 inch system to a 3in
7hp gained
14ft/lbs TQ gained!

See now with the 3in sys I can run open with the cut out and there is essentially no difference. See a near perfect exhaust system will actually have little to no difference with a open cut out!!

 

Remember this a 3.4 with the 2.8 top end on the 3.4 block!

got a bit more in the works too to help the numbers a bit more...

3 custom chips ready to be tried out to see who will work best!
MSD box...1.6 rockers...custom built plenum and runners w/ 65mm TB (what the car need for decent HP #s)...Larger fuel pump...heads will get a valve job, further port job, milled, with possible valve enlargement...

And a bit further down the road...turbo!

 

What the car has had done to it as of now...mods and minor upgrades...

****************************************
Engine swap: 1995 Camaro 3.4L V-6
SunCoast Ram Air Box
K & N Air Filter
MAF sensor screen removed
Throttle Body coolant bypass
EGR System eliminated
19lb Ford fuel injectors
Holley Adjustable Fuel Pressure Regulator
MSD Dual Connector Coil
Accel distributor cap and rotor button painted red with brass contacts
Taylor Spiro Pro 8mm Wires
AC DELCO Rapid-fire plugs
Distributor blueprinted
Gasket match ported & polished: Plenum, Runners, Lower intake, & heads.
Reed Cam: TM276/282H12A2 (223/228 w/ 471/480 lift on 112 int C/L is 108)
Comp Cams timing chain set, lifters, & springs
Sneaky Pete NOS system
ASP Underdrive crank pulley
PF&E 304 stainless headers
Custom 2.5 inch y-pipe
Flowtech 3in. cutout
Magnaflow 3in. high capacity catalytic converter
3in Flowmaster American Thunder catback system
Custom dual 2.5 in outlet pipes w/ 4 square tips
Chrome Spectre breather filters
160 degree thermostat w/ Hypertech fan switch
Aluminum 4th Gen Driveshaft
1994 4th Gen Torque Arm
TransGo shift kit
Neal Racing Transmissions 2800 stall converter
TCI transmission cooler w/ Earl’s –6 AN fittings and stainless braided lines
Neal Racing Transmissions Performance 700r4 rebuild with all the goodies

 

hehe sorry I could have told you that...

Alot fo people said the same for that, but I had one of the faster 3.4L v6s n/a...

know what my exhaust was at the time... stock y-pipe into a $20 muffler...


also ran a 2.75 in catback(stock z28, and muffler, and got a nice gain) I then rain a cutout before the CAT(sort of open y-pipe) it slowed me down but then I made a partial "block off" cover and I ran better.

 

redraif, you're on here too?? lol.

 

YOur in Central FL? check out the fl section here, and the FL v6 section at www.camarov6.com

 

Got a sound clip of it?

 

yup, I'm in tampa!

 

Sometimes...usually I get harassed quite a bit more, so I just post occasionally! PLus the v-6 tech has not been as helpful, since there are more 4th gens on the board (3.8s). I have asked a few questions and typically not gotten much help! Can get confusing which 6 the post is refering to! Had better luck with TGO!

 

On VHS! its not nearly as impressive as in person though! I want to try different recording techniques to see what will get it recorded closer to what you really hear in person! Any ideas! I really want to get a sound clip up online!

 

i have that one clip of mine idling with open headers...it was shot with a regular video camera, it sounds good!

 

Hey I saw you @ Gathering 9! I remember you! Thats right I heard your car all the way from atop the parking lot while you had it running for the sterio contest! Sounds amazing ESPECIALLY for a V6... I coulda sworn you had an 8...