Well guys my birthday is comming up and I would like to add a 2.5 exhaust to my turbo cavalier and get rid of the stock one. My questions are is going from the stock to a 2.5 inch exhaust really going to give me any gains? Is the anybody running the Megan Racing exhaust with there turbo setups and is it really 2.5 inch diameter? I did a search and reading through I could not find the answers to those questions. I heard that it might be a 2.25 inch exhaust and not a 2.5 inch so I am just wondering. Thanks in advance and I might even just make my own setup just looking at my options.
~Boost. Its what's for dinner!~
just go to a shop, and have them mandrel bend you one.
Portage, MI
My question is how are you getting any gains
without changing your exhaust? That should have been done with or before your turbo IMO. Other than that yeah, better off just getting a custom-made exhaust system made from a local shop.
actually you should notice nothing short of great gains from a bigger exhaust... 30 whp more if you're running say 8-10 psi is not far fetched, IMO, but I might be wrong on the numbers...
15.574 @ 89 mph stock without charger. new times with charger coming soon.
Alright. I am planning on going either with the megan or constructing my own. I think I can do if for about half the price if I do my own. I just don't know what I want to do for the actual exhaust part though....I almost want to run it just from the cat back no sort of exhaust. lol, but I will do some pricing and see what I come up with I guess.
~Boost. Its what's for dinner!~
for the greatest gain, go from the turbo back. high flow cat, long resonator (unless you like your exhaust louder), straight thru muffler. 2.5" piping would be good....3" would be better.... and yes it fits if done right.
_________________________________________
450WHP Turbo Ecotec swap in the works...
Follow the advice of the people above. Turbo-back go at least 2.5", 3" if you can. The idea is to get as much exhaust out and away from the turbine as possible.
Straight through is your friend... it's louder but it flows a lot better. And if you can afford it, get a full mandrel system. Exhaust is probably the 2nd most important part of a turbo setup so do it right the first time so you don't have to waste $$$ later fixing mistakes.
-Chris-
-Sweetness-
-Turbocharged-
Slowly but surely may some day win this race...
Smallest I would go would be 2.5 inch...
But are you turboed now? I am confused, or are you going to be turboed soon?
Turbo will be done next week. I have a 3 inch down pipe mocked up now and I was thinking that with the 2.5 inch exhaust after that would be okay.
~Boost. Its what's for dinner!~
if you already have the 3" downpipe just make the rest of the exhaust 3" to match. no sense in reducing pipe size from front to back.
_________________________________________
450WHP Turbo Ecotec swap in the works...
alright... I will look into doing that then. Now can you run a 3 inch exhaust following the stock design or does it have to be re-routed? Thanks in advance!
~Boost. Its what's for dinner!~
Yeah ^^^ listen to him. If you have a 3inch downpipe there is no point in reducing the airflow and not maximizing efficiency by keeping 3inches. Usually the accepted sizes are 2.5'' for S/C and 3'' for Turbo. I would go with custom and try to get mandrel bends if possible, causes the least amount of airflow reduction
Timothy Pietraallo wrote:alright... I will look into doing that then. Now can you run a 3 inch exhaust following the stock design or does it have to be re-routed? Thanks in advance!
Follow the stock pipe routing and make the part that goes over the rear axle is up high enough so that it doesnt hit every time you go over a bump. It'll fit fine if it's done right.
_________________________________________
450WHP Turbo Ecotec swap in the works...
Blown DanteMustDie wrote:actually you should notice nothing short of great gains from a bigger exhaust... 30 whp more if you're running say 8-10 psi is not far fetched, IMO, but I might be wrong on the numbers...
i doubt you will get 30whp from it on our cars. thats a little high.
one of the main reasons is to decrease spool time.
"Growing old is mandatory. Growing up? Definitely optional."
^right. The turbo will spool more quickly because less backpressure in the exhaust will mean a higher pressure differential across the turbine.
fortune cookie say:
better a delay than a disaster.
Do 3" you will be very happy! Mine hits the back axle every once in awhile since the car is lowered but my 20g spools up a hell of a lot faster now. The car isn't really too loud either, just a magnaflow race muffler and resonated tip. I also noticed I went up to 11psi when before my max was 9psi.
