i'm currently cobb stg.2 and am looking at going with an FP 18g. i will of course be getting a big TMIC, modding the stock injectors, fuel pump, one step colder plugs. then i'm getting a tune for both 91oct and E85!
i already gutted my stock UP and took out the EGT sensor and plugged the hole up with a bolt. i'm wondering if there are any gains to be had or advantages with getting an aftermarket UP. i remember hearing that they are, atleast some of them, larger in diameter than the stocker.
Alot of people will say that there is no real advantage to switching at this point. You have already went through the trouble of modding your stock up. I am of the opinion that there are some advantages to an aftermarket up pipe. The stock one is not the same diameter all the way up for one. During my research, before I bought my up, I read that if you increase the diameter of the up pipe you will lose exhaust velocity. This will increase lag. I choose to replace the up pipe with a stock diameter pipe.
i had both. the gutted stocker was good for the stock turbo, but when i went to a vf-39 the stock up was causing some problems, and my tuner Dom couldn't tune it, very agressivley, so i switched to a cobb uppipe, which is close to the stock diameter, and have had zero problems after my re-tune
If you can swing the price, Cobb is a great unit. It's cast which will hold in heat better. More heat=more exhaust velocity=quicker spool up
I went for a thin walled up with a flex section because i could not swing the price at the time. I think I will swap them when I get my TD05 18G 7cm^2.
i bought a turboxs up pipe and im very happy with it, stay away from the up pipes with that flex hose part in there that is a joke and will come apart like it did to mine and took out my VF22 now i have a evo3 big 16g
I went with a Helix uppipe with a flex section so that I wouldn't run into issues with the uppipe leaking in the future. 3 years and no problems thus far. The Helix uppipe was also larger then stock because I anticipated upgrading the turbo, which I havn't done yet, but I haven't noticed any disadvantages with the larger diameter.
Any increase in lag from the larger diameter was more than made up for by removing the cat. Going to a larger turbo will exasperate the issue though. i would imagine the increased volume might make up for the decreased velocity in the higher RPM's.
thanks for the replies. sounds like there would be some advantage to an aftermarket because of an even diameter all the way through and a cast one would keep some heat and increase spool up. i'm all about that. nagy, was it only when dom tried to go aggressive that he had problems?
i really would rather not spend $235 on the cobb pipe. i know i have seen some that are more like $100. can anyone point me to a good UP that is cast, same diameter as stock and relatvely cheap?
also, i'm looking into getting some heat wrap. i was thinking of wrapping the UP, hotside of the turbo and first part of the DP. would this help out with heat retention and spool? i also no longer have a heat shield, would this help with heat soak or is a shield absolutely necessary?
He could tune it but it wasn't that aggressive, and it was at the point that he was unsatisfied with it. After I got the Cobb he had no problems at all. I would spend the money on a good quality uppipe like the cobb.
Thats a good mentality. Dont skimp on something that might come back to haunt you later.
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