Hi,

Can anyone tell me what (if any) power gain I have now from replacing my stock system with the following?

1986 Camaro 305 IROC TPi Auto - Posi Traction Diff

New exhaust:

Flowmaster American Thunder 3" catback system.

These systems are so hard to find over here in England, and the shipping is so savage that I went out and got this from a UK seller without researching other options.

It sure sounds sweet, and feels like it picks up and goes better than before.

Thanks.http://store.summitracing.com/defaul...=KeywordSearch

 

i dont have a real time dyno figure, but i would guess 10-15hp.

if you replace the stock cat with no cat or high flow cat, and then add some headers, you can see 30hp more.

my L98 went 13.89 at 97 with only flowmaster catback, stock cat, hooker headers, air box mod and 2800 stall. on stock 2.77 gears. so i know i picked up alot of power from the 3 mods. with 3.27 gears i'm trappin 100mph, almost 101. thats near 300hp on motor up from about 250ish stock. (most will put down 210-215rwhp stock which is near 250 crank, i think they are slightly underated)

 

if ur just replacing stock...go for it. looks good, sounds good, great price. i have the same set up. if i was to do it again i wouldnt, but for the price u caint go wrong. and yes it will flow better than stock....

 

it'll flow better than stock but there are better options.

I'd say 10 rwhp.

 

It would have been pure luck if I'd bought the best system available, but being as I'm on the wrong side of the pond there is very little to choose from here.

It's improved the look, sound and performance (a little) without the need for any major work underneath, so I'm pretty happy.

10rwhp is about what I expected. Eventually I plan to make similar mods to Orr89RocZ over time, but i'm not trying to build a flat out racer anyway.

 

GM high tech did a test once and got 7 at the rear wheels.

 

not a bad way to start. headers and exhaust and airbox makes lots of power on these cars. bone stock the car should trap 96mph or so. now i'm trappin 100.9 with those mods and gears and a converter. so it does pick up some power.

 

Catback alone doesn't 'make power' per say by itself, but once you add more exhaust mods like headers and open up the intake such as runners, filters ect, it will help alot.

 

^ yeah its best used with full air flow system

but takin a look at stock exhaust system... its VERY small and restrictive. the bends are horrible looking and not uniform

upping the size to 3 or even 3.5inch with good mandrel bends will definately help flow... even tho the 80 series only flows marginally better than stock mufflers. it sounds pretty good tho, but a custom system would be nicer for more power

 

Turns out the previous owner pulled all the bits out of my cat anyway, so thats one less thing restricting flow.

I bought the system more for sound than power gains anyway, but was interested to see what I'd benefit performance wise as well.

If my car was in average condition, I would just strip out all the air con and weighty bits and go for performance. With these cars being a rare sight over here in the UK though, I'm trying to keep it standard looks wise, with just minor mods.