i have a cast iron turbo manifold but with the turbo on it there is almost no room for the downpipe to fit in between the turbo and the ac compressor, some people seem to have luck getting it in there but i haven't. the only way i can get it to fit is if i make a 90 degree angle with the pipe, but that doesn't seem like it would flow well at all. so my question is should i use what i have or sell it and get a manifold and downpipe from go-autoworks or some place like that?

 

Sell. start over.

 

How much power are you really aiming for? If its not too much just go for the 90 bend and make your freakin DP, when i had a cast mani i had all kinds of harsh bends on my DP and i made 317whp easily, granted it was a 3" dp...

 

Well put, if the original poster makes one out of 2.5 material, the bends will still be smooth, its when you go up to 3 inch you start having to use cheater cuts. It really all depends on how much power you want in the long run.

 

yeah i'm only looking to make 250whp, but i can't seem to find a place to make a sharp enough bend. i cut a pipe in half with a 45* angle and made a 90* angle out of it. would this be ok? it seems like the exhaust would just hit a wall and not flow good.

 

It will work but it won't be efficient,why would you spend so much money on making the car faster, but resort to downpipes that restrict flow and hurt the setup ?

If you use 2.5 inch you can get a nice bend off the turbo, go from 2.5 to 3 inch under the oil pan.

 

I couldn't find anything that would clear mine in 3" so i made my own bend. Might be a little restrictive but ill have to wait till i take it to the dyno to see.

 

that is perfect, i need to see if i can find some place to make me one of those. do you mind if i copy your idea?

 

That type of DP fabrication has been around for YEARS, before mandrel bend machines were more readily available. (I like pie-cuts). It can get VERY expensive due to the labor intensity

 

do you know what the average cost is roughly?

 

Mine was very similar to this as far as bends, no problems with excessive back pressure or anything. In fact i don't think its restrictive at all, if thats restrictive then a ramhorn mani must be too

 

i think i'm going to attempt this myself, if i can tack weld the pieces it shouldn't cost too much for a shop to finish the job right?

 

As long as they don't charge like $20 per weld!!