3" Down Pipe Install

[msharkf2]

When installing a 3" downpipe to a stock turbo, do you just use the stock replacement "doughnut" to mate the downpipe to the turbo. The new doughnut I have is like a graphite material. Also, the original bolts with the shank and springs will not fit the 3" pipe. The pipe is too large on the inside bend (bolt is too long) to get the bolt in the hole of the flange and on the outside bend the spring will not seat onto the flange (the spring interferes with the pipe itself). I got the downpipe from Kirbans. Do you just use regular bolts (metric of course) and snug them up. How tight should I go with these bolts? I don't want to ruin the doughnut but I also dont want it to leak and have to replace it later. Any tips or tricks? Thanks Mark

 

[coach]

Are you using the stock cast iron elbow, or is it a complete down pipe?


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[Heisenberg]

It's probably this one.

I for one would not use "regular" bolts. They will corrode quickly, and snap easily from the heat and the stretching.
At least use Stainless, or preferably Inconel.
Stainless M10 (I believe, could be M8) - in a pinch

Notice in his picture - the 2 Allen Head cap screws.
Dennis knows what he is doing - so in all likelihood, he furnishes the 2 cap screws suitable for the DP temps. Yes / No?

The usual torque settings for metallic donuts are in the range of 30-45 lb / ft.
However- not sure about your "graphite" sounding one.
Whatever - you don't ever want to crank on those flanges - or they tend to "oval out" on you.

He probably eliminated the spring design for his DP to acommadate the larger pipe I.D / O.D - and went with just bolts.
The springs are there for taking up slack during heat cycles, and to save you from re-tightening the flange on occasion

"Down pipe comes complete with instructions, clamps and some tips on how to port the turbo exhaust housing before installing this new down pipe. Fit is excellent because of its unique two-piece design. We recommend these be installed by a qualified mechanic."
No instructions on the bolt ups?
Or - Have you tried sending Dennis a message?

 

[earlbrown]

Stainless with nicklebased antiseeze is the way to fly. A steel bolt will come back to bite you at the absolute worst time.

Also, if you want to maximize the benefit of that pipe, you need to port that lip out of the stock cast elbow.

 

[Heisenberg]

Stainless with nicklebased antiseeze is the way to fly. A steel bolt will come back to bite you at the absolute worst time.

Also, if you want to maximize the benefit of that pipe, you need to port that lip out of the stock cast elbow.

Because the nickel based stuff doesn't burn off?

Those Inconel bolts and studs are the bomb (for turbo fasteners) too Earl.
But pricey and mostly mail order.
You ain't gonna find them in the fastener section at Home Despot.

 

[Heisenberg]

The new doughnut I have is like a graphite material.

Probably like Brian's donut

http://www.gbodyparts.com/product_info.php?products_id=1094&osCsid=91ebcfb298cd1ddd19fc5711e31931b8

 

[earlbrown]

That pipe looks like a Postons pipe I put my hands on years ago. It had a small lip that recessed into the cast elbow. If that's the case it seals up with RTV and heat. I wasn't very impressed with that pipe. It was a bitch to keep the bolts tight. I will image with a gasket giving way, it'll be blowing out left and right (and losing bolts without constant attention)

It does look a lot better if you lose the Ubolt clamp right below the turbo and it'd be a good idea to order a stainless band clamp for the bottom or just leave it loose so it can float.

 

[1952ray]

I have this pipe. Do NOT use the donut. I did take the exhaust elbow off and mill a pocket for the short pipe to fit flush. Just use RTV, didn't even need the clamps. Zero leaks