3.5"-4" downpipe fitment with AC/PS
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From: Idaho Falls, ID
3.5"-4" downpipe fitment with AC/PS
Does anyone have pics of bigger than 3" downpipes on an evo with both ac and ps retained? Is it even possible to make the bend? Only way I can think of is to pie cut the first bend.
Reccomendations?
Thanks,
Josh
Reccomendations?
Thanks,
Josh
Your thinking is correct on a standard placement kit. If you were to run a top mount you would have some more room.
The problem with the precision v band is that the tube slides over top of the flange and it alone takes away 1/2" of clearance. You'll have to find a tight radius 3" bend and then expand it to 3.5 or 4" after you've cleared the ad compressor.
When I was building my manifold I placed the turbo so that it was as close to the bell housing / mount as possible and I only had 3.5" of clearance between the turbine housing and a/c compressor.
Also I was using the same s style compressor cover as you.
Most places you get bends from start at a 1.5 x the diameter of tube for the radius, so if you were to buy a 90 and cut it at its tangent you would have a bend that is 4.5" from flange to edge. (on 3" tubing) so no you add the precision vband flange and you're at 5". So realistically you'll want to cheat or pie cut the first few bends.
If you look how close the turbo is to the bell housing, you can see the placement
Attachment 330900
When I was building my manifold I placed the turbo so that it was as close to the bell housing / mount as possible and I only had 3.5" of clearance between the turbine housing and a/c compressor.
Also I was using the same s style compressor cover as you.
Most places you get bends from start at a 1.5 x the diameter of tube for the radius, so if you were to buy a 90 and cut it at its tangent you would have a bend that is 4.5" from flange to edge. (on 3" tubing) so no you add the precision vband flange and you're at 5". So realistically you'll want to cheat or pie cut the first few bends.
If you look how close the turbo is to the bell housing, you can see the placement
Attachment 330900
Last edited by ExileMFG; Jun 28, 2014 at 04:09 PM.
Thread Starter
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From: Idaho Falls, ID
That's pretty damn close man, looks way good. So is there no way a 3.5" or 4" downpipe will fit then? Looks like 3" is the only way to go until I get under the oil pan/past the ac compressor like you said
That manifold does bolt the turbo in a different spot, I would bolt up your compressor and v band flange and measure the distance you have available. It could be possible, but it will come very close or even touch.
I have a 3.5" mandrel bent downpipe on my custom top mount setup with plenty of room. I even have a transition off the turbine housing and could easily have fitted a 4" downpipe.
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From: Idaho Falls, ID
That looks good man, but a top mount setup usually yields more room for a downpipe, as you have a little more vertical room to work with. My problem is it's pretty tight as-is, and trying to find a tight enough bend and clearing everything can be a chore it looks like. Not sure what I'm gonna do yet
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