06MonteSS

on our cars, is there any real big benefit to increasing the cat-back pipe from 2.25" up to 2.5" or 3"?? it's not like these are high HP engines, so I was wondering if we would actually degrade our low end due to less back pressure from the bigger pipe...

thoughts??

Taz34SS

iTrader: (2)

Talk to JPH on the board. He has a great background on all the LS* cars and he told me that if you go too big, you will lose low end. I would stick with a nice 2.5 system and you will be just fine.

djfeezy

Not too concerned about low end when it came to my exhaust size. I spin through first too much as is if I don't feather my launches. I went with a 3" exhaust and have no regrets.

hexxLS4

iTrader: (1)

Spin through through first might be bad...but so is the uber weak pull at the top of 2nd....need all the low end torque we can get there IMO.

06MonteSS

that's what I was thinkin'...

think maybe I'll just remove the u-bend and put on new mufflers - and keep the stock pipe...

Mels SS

iTrader: (1)

I was thinking the samething just a set of Magnaflow mufflers

Nacho SS

iTrader: (4)

I got 3" and I love it. Get a tune if you don't like a uber long 2nd gear pull, change the shift points firmer, and get rid of torque management (the biggest culprit). And towards the top end of second, 3" pipe actually helps push more out of the engine...helping top end output.

With a larger diameter pipe, you can feel/hear the better flow towards the top end of each gear. The cars have plenty of giddy-up down low. If you couple the 3" pipe with a rocker/pushrod/spring mod, there will be a top end gain.

hexxLS4

iTrader: (1)

Or you can tune AND keep the low end torque with the smaller exhaust....*shrug* Question, what is the highest speed the HP tuner can take second down to before it shifts? Right now, I have to let it wind down ALL the way to 35 to get it to downshift into first...really annoying! Makes this car really sluggish of a roll.. Would be nice if it was more like 40-45.

djfeezy

What ever you set it at. IIRC

hexxLS4

iTrader: (1)

Ok rephrase question, where is the sweet spot to set it at? Or where do most of you set it?

DavidGXP

iTrader: (14)

I don't see us losing too much power if the A/F ratio is correct. The 4.6L Mustangs use dual 2 1/2" pipes and make 300hp too. Plus it's a smaller motor.
I'd say go for it.


Just for the record.... I believe the rear exhaust manifold to be the biggest restriction. I'd love tho have these manifolds ported, extrude honed and coated (wouldn't we all!) $$$$
Also, the crossover pipe seems kinda small.

Nacho SS

iTrader: (4)

Yeah the manifolds are terrible. Someone needs to make some block huggers (probably the only thing that fits)...PM camaroextra, he may make some custom ceramic ones.

DavidGXP

iTrader: (14)

I'm going to pull the crossover pipe off and wrap it with header tape. So while it's off I'm going to start measuring. Hogan is working on a crossover pipe, but it won't be out for awhile. I'm a good buddy, with the guy's down at Stan's headers in Auburn, Washington. So I might see what they can do for a crossover pipe (2 1/2" ceramic coated). They already quoted me for a set of custom headers and we're looking at 1800 bucks with install (duh!!!) Stan, said that if he was to mass produce them then then price would come down since he would be able to build a fixture.
I posted a bulletin awhile back ago but it got deleted.

They recommended running a 3" down pipe all they way back into the split and 2 1/2" after the split into duals, using Magnaflow mufflers. But I'd go with
http://www.aeroexhaust.com/car_exhaust_2525.html (They only weigh 7Lbs each!)

djfeezy

I'm sure if they would make some headers, we would buy them! I know I'd get some as soon as they came out!

Nacho SS

iTrader: (4)

Headers would definitely be high up on my buy list.

David, that site is nice, I really like some of the tips they had. Our piping is 2.5 stock right? I've had numerous people ask me where to get decent tips that fir the stock system.

06MonteSS

I know our muffler in/out and tips are 2.25"...

looks like the pipe is 2.5", goes down to 2.25" for the y-pipe, then each muffler is 2.25" in/out...

kpssmonte

The pipes in/out of the resonator are 2.25" as well.

DavidGXP

iTrader: (14)

Yes I was going to have Stan build some headers using my car as the ginne pig. He's no dummy and wanted me to dyno tune my car first. Stan knows all about group buys and just finished a Soltice header for some members from a different site. He claimed it to make a 65hp gain!
So... I was trying to get something together here on this site but I apparently hacked the administrators off. (Sorry...!!!!)
I really don't see any gains to be made until we get these manifolds to flow, or replaced.
People say that they flow, but how do they know? Do you guy's who say this shitt really think that it's ok, to run another manifold into another (through a crossover pipe)
Manifolds are restrictive enough! Especially when trying to run 8 cylindes through a
a single four cylinder manifold, and I don't care if it's got a 3" outlet! (Talk about a giant heat sink wow!!!)

So screw different pipe diameters, different mufflers, different crossover pipes,
cats, air intakes, pulleys, spark plugs, coil packs, wires, ground straps, and high lift rocker arms with weak stock springs, and cams! Headers is what we need! Too many people on here crying about not making enough power with simple bolt ons (hmm... I wonder why???) We can't put in what we get out out
I bet we would make an easy 335-350 at the engine with headers.

Taz34SS

iTrader: (2)

Im in for headers aswell.