LT Malice

iTrader: (3)

I have had my turbo kit for over 2 years now. I have always been fighting with tiny exhaust leaks between the cylinder heads and turbo manifolds. I've tried alot of crap to solve them, but they always come back.

I've tried 3 different kinds of header gaskets
I've tried 2 different styles of manifolds
I've had new flanges put on my manifolds. They are now over 1/2" thick.
I had someone build a turbo support bracket, to take the weight off the manifolds to keep them from warping.
All of those steps solved most of my leaks, but I can never fully stop the #1 cylinder from leaking on the front of the driver side cyl head.

WHat else can I try? Would copper spray work on my header gaskets to help seal them up? I know people use that stuff on MLS head gaskets.

Johnv

have you had the manifold face, surface ground to make sure it is dead flat ?

maybe you have a backpressure issue with manifold or turbo ?

LT Malice

iTrader: (3)

yeah, when the new flanges were welded on, they were machined flat.

I never considered backpressure being an issue. I do have small crossover pipes going into my turbo, maybe they are causing the problem.

THE_SUPRA

i know abunch of turbo mustang guys just use a thin layer of Copper RTV and torque the manifolds down with no other gaskets.

kbracing96

iTrader: (25)

You might try over sizing the header bolt holes a bit, especaly if the headers a SS. SS expands A LOT when it heats up and if the bolt holes aren't large enough to allow for the manifolds to expand, then it will bow the flanges out and let them leak. Just an idea.

Ping King

iTrader: (20)

What style manifold do you have? You should drill the flange holes out slightly larger. Starting at the center and going larger as you go out. I would also use washers under the header bolts. Some people also go as far as cutting the flange into seperate pieces.

LT Malice

iTrader: (3)

Hmmm...

All good ideas. I'll start by oversizing the bolt holes.

stevieturbo

Perhaps after a couple of good heat cycles, then re-machining the surface, it will be fine ??

I know it was always a PITA on my old TT setup. It was another contributing factor for me choosing a blower.

LT Malice

iTrader: (3)

I have log style manifolds.

I just pulled them off and inspected them. Both cylinder banks are leaking at the front cylinder. That leads me to believe that there are backpressure issues because of my small crossover pipes.

I think I'll just accept the fact that the system is gonna leak, and swap in an LSX when the ol' V6 finally blows.

Ping King

iTrader: (20)

did you cut the flange so that it doesnt try and bow?

LT Malice

iTrader: (3)

no I didn't. The flanges are over 1/2" thick, so I really don't think warping is a huge issue.

stevieturbo

ive made flanges from 15mm steel ( almost 5/8" )

Warpage can still be an issue. The amount of heat and expansion and contraction involved here is massive, even more so with log style manifolds.

Ping King

iTrader: (20)

logs have strange expansion properties. i would still say you need to drill the holes out on teh flange like stated previously, and make relief cuts in the flanges so theyre independant

LT Malice

iTrader: (3)

will do.

qqwqeqwrqwqtq

Header studs would also help.

LT Malice

iTrader: (3)

2 of my 6 holes on each bank are studs. If I have more than that, it's impossible to install the headers. The up/forward sweep makes it impossible to reach the stud to put a nut on it.

RealQuick

iTrader: (14)

Thats what I'd try next. Cut the flanges and then crank em down.

LT Malice

iTrader: (3)

My flanges are at the machine shop now getting resurfaced, bolt holes slightly bored out, and slits cut in the flanges.

93formto98T/A

iTrader: (28)

I was in the same exact boat with my log/TT kit. I had the left manifold shake loose every once in awhile and kept blowing out the gaskets so I got a set of SCE copper gaskets from SCPC and have had Zero problems since then. Even if it gets loose, the copper gasket will remain unharmed and all I have to do is re-torque the header bolts.

Old Geezer

iTrader: (3)

Common hardware will not take the elevated heat levels. They will lose the heatreat, and the applied torque will drop off. This includes the lock washers, if used.
A good grade of stainless in necessary, installed with hi temp antisieze.