Engine/Transmission (1994 - 1998) What size exhaust housing should I get?

[Erik.Miller]

I need advice on what size turbo exhaust housing to get as I currently have a stock 12cm. My objective is to reduce my EGTs. I have a 4" MBRP that arrived in the mail today. By the way, I will be eliminating the cat with the new exhaust, so hopefully this will help my EGTs. While I am installing the exhaust, I figured it may be easier to go ahead and do the exhaust housing at the same time since they mention having to move the exhaust to accomodate a 16cm housing. Please give me some advice on whether I should go with a 16cm or 21cm housing. I plan to add injectors at some point after I get a transmission upgrade. Will the bigger exhaust housing work with the injectors when I add them or will I eventually be looking at a bigger turbo?



Thanks in advance for the advice.

Erik

 

[KingS]

depending on the hole size in the injectors you will need a bigger turbo not just for more air to keep egt in check but to keep the boost pressure from taking out the compressor wheel in the stock turbo.



Plus the bigger turbo is needed to provide the air and boost to get you all the hp that you are capable of getting from the injectors and truck setup.

 

[Matthug]

The 16 really only reduces peak EGT's, usually about 100 degrees. You will have higher cruising EGT's though, but nothing dangerous. I like my 16, although I'm still running too much fuel for any HX35 to handle so it spools faster than the stock turbo did with the stock plate full forward and 300 injectors in.

Anyway, do NOT go larger than 16. My cruising EGT's are plenty high enough, can't even imagine with an 18. 5 or 21cm housing.

The exhaust alone should lower peak EGT's atleast 200 degrees if you are still running a CAT and stock muffler. I would put the exhaust on and leave the 12 housing personally. I put my 16 on later and it was no big deal to move the exhaust up 1 inch. Save your money on the band aid 16cm housing fix and buy a real turbo that has a bigger compressor too.