cam

iTrader: (9)

Just curious who has done it and if there was big improvements. The big heat spots on mine are right where the header collector goes from 3" to 2.5" y pipe. Everything else looks good so I wonder how much I would gain from going to a dual 3" y and a single 4" intermediate/muff combo

cam

iTrader: (9)

No one???

Regal1

iTrader: (4)

I have a dual 3" into 4" ORY and had it reduced to the stock catback. I recently installed a piece of 4" pipe and a Borla oval muffler and dumped before the axle. I didn't dyno it but it picked up .07 sec and over 1 mph in the quarter, and that was in worse weather than my previous best.

SouthFL.02.SS

The 3" mufflex/QTP Y-pipe (which includes a 4" flowmaster Y merge collector) combined with any free flowing catback works well. I had this setup (using an SLP 2OTL catback), and it performed really well- holding up to the TD's that were previously on the car.
Going 4" all the way is for max'ed out 346ci Heads/Cam or larger cube setups.

cam

iTrader: (9)

Cool thanks. So you guys figure just running a 3" y into a 4" collector then down to a 3" catback would be noticeable and worth the effort? Its very easy to see where the heat spots are on mine as the entire exhaust is stainless. The discoloration is most noticeable right at the 2.5" drop to the y I have now.

RE AND CHERYL

iTrader: (31)

I don't call that a difference at all. Weather accounts for that easily. As the 4" dumped pipe will cost you a lot of low end tourque I'm guessing your 60' was better than before (less wheel spin) and gave you the 1mph.

A 4" system is is an overkill in most cases. If you outgrow the single 3" I'd go true duals before I'd go single 4".

Re'

Regal1

iTrader: (4)

Hotter, more humid air makes a car run better, where have i been?! My previous best was last october, it was 45 degrees, virtually no humidity and at night. After changing the exhaust and running this summer when it was 85, 30% humidity and at 4:00 in the afternoon it improved by 3/4 of a tenth and damn near 1.5 MPH. So i'd say its a huge improvment. Thats probably 1.5 tenths in the same weather.

The car never spun on any good run I ever made and its and automatic with a torque converter so i dont care how much power I make below 3400 rpm. Plus the 60' was only about .03 better.

I don't see a single 4" being much more overkill than 2.5" or 3" duals dumped before the axle. Plus with duals, you dont have as many torque arm options ans I lost about 20 lbs compared to a full catback and probably about 10 from duals.

5_02ls1

iTrader: (20)

takes 10 hp to gain 1 mph or 7hp to gain .007....
RGAL1 has been here 2 years you have been here 3 mo
ill take his word on it.....

to the op anytime you go bigger on exhaust your gonna gain power....who cares about low end tourqe thats what stalls are for...I sy do it....

tylerdj

iTrader: (31)

This is from the sticky

01 BERGER CAMARO SS

iTrader: (77)

Thats what Ive would have said.

MikeG

iTrader: (33)

Regal1, I'm sure you get this alot, but why do you have an LS1 intake on an 02 car?

Regal1

iTrader: (4)

The guy I bought the car from swapped with his buddy before he sold the car to me and when I bought it I didn't know the difference.

jason99frc

iTrader: (12)

I'm about to do the swap on my car and I will have before and after #'s to share but iyt may be 2 weeks before I gewt around to doing it.
Sawp details:

Current setup:
Grotyohan(sp) 1-3/4 headers into Grotyohan Y, twin 3 into 3" bullet

New setup : Cut Y pipe and weld on Flowmaster Y TWIN 3" IN AND 4" OUT PN Y0300400(I THINK) THEN A 4" BULLET. I have all the parts but I just havent had the time to do it and things dont look so good for the next few weeks either as work is killing me. When I do get it done I will post some #'s.