Warped Turbo Manifold

[MaTTSuN]

I have a 81 turbo motor with the stock turbo manifold. It was starting to leak allot so i figured it was time for a new gasket.

Everything was straight forward and lokoed fine until i put it back on the head. The bolt holes seemed a little off but i got it to fit.

On start up i was hoping i would have the sweet purrrr that i have missed for a month now with the leak

but no the #6 port on the manifold was leaking on the underside so it has bent up a fair bit to be misaligned.

I put header wrap on the manifold and drove it for a year. could that have kept to much heat in it and curved up the back port a little?

 

Their is not much i can do about it now because im going to Japan soon just wondering if anyone had a similer experience.

 

thanks

Matt

[evildky]

I had an issue blowing out the exhaust gasket around the #1 exhaust port, the header and the manifold as the head both had some pitting from years of coolant leaks around the thermostat housing, I had both surfaced milled at the machine shop, no more leaks, if your's is just a warped manifold have it milled

[Brad-ManQ45]

You might also want to provide more room for the two slots on the end to expand w/o touching the studs in them - the manifold will lengthen and jam the inside edge of the slot against the stud = leaks and possible stud breakage.

 

I've already ground out the insides of the slots and smoothed/port matched the manifold and hogged out the passage from the first four cylinders to the plenum on mine.

 

I will use stainless studs when I mount it - it is going to get Jet-Hot coated...

[zeeboost]

This settles it - I'm removing the exhaust wrap from my turbo manny. I purchased this manifold from another user on here, and it came with exhaust wrap already on it, so I figured why not. The first couple of months or so of driving with the new turbo setup, I ran the exhaust open turbo (well, it had like a 3 inch long pipe, but still...), so obviously my ringing ears wouldn't notice any small exhaust leaks. But, once I connected the exhaust up, it was more than prominent. After another month I couldn't take it any more and decided to hunt down the leaks. I noticed #6 runner was leaking pretty badly, along with the turbo flange. So I pulled everything and found that almost every runner was warped (didn't even need a straight edge to tell) along with my turbo flange. Even on the gasket you could see soot where exhaust gasses had been blowing by. I'm running a T4 turbo, and I purchased the T4 adapter plate from Boost Logic, a well-known high performance shop in Austin. It's a high-quality adapter ran on high hp supras and whatever else they have come through the shop, so I'm pretty convinced it didn't warp due to inferior material. I've never seen a manifold warped this bad. My previous manifold was on for at least a good 6 years without any leak issues. SO, I'm pretty convinced this was caused from the exhaust wrap. I know there have been a few on this board that say they've been running the wrap without any issues, but I don't know what else it would be...and the wrap makes perfect sense if it's trapping too much heat. So I've had the exhaust runners and flange milled down, bought new gaskets, and will be installing this without the wrap. Guess I'll see how it goes.

[Nigel]

The turbo manifold on the bone stock L28et I picked up was warped. There were no signs of overheating. I had it ground flat ( probably would have been cheaper to get another manifold for the ridiculous amount it cost me!), and hasn't leaked yet in 8 years and 20,000+miles. I've had a header blanket over the top it for the past 5 years.

 

One other note... I had grind down each of the thick washers that are shared between the intake and exhaust manifolds to make up the resulting difference in thickness.

 

Nigel

'73 240ZT

[MaTTSuN]

I have been thinking about making a jig for my manifold and heating it up bending it back and bolting it down. let it cool then it should be good to go again.

Sounds easy but it might turn into a nightmare. Im back home in a few weeks, might just drop the N/A back in for the winter while i sort out the turbo engine.

[Challenger]

The turbo manifold on the bone stock L28et I picked up was warped. There were no signs of overheating. I had it ground flat ( probably would have been cheaper to get another manifold for the ridiculous amount it cost me!), and hasn't leaked yet in 8 years and 20,000+miles. I've had a header blanket over the top it for the past 5 years.

 

One other note... I had grind down each of the thick washers that are shared between the intake and exhaust manifolds to make up the resulting difference in thickness.

 

Nigel

'73 240ZT

 

Header wrap and a blanket would be a little different. Id bet on the header wrap trapping alot more heat than the blanket.

 

I removed the heat shield on my n42 intake and was going to do header wrap since Ive seen it do wonders on other cars but Im thinking about just putting the heat shield back with a turbo blanket.

Edited August 26, 2010 by Challenger

[MaTTSuN]

Well i got the Jog started, here are some pics. Ill have to brace it up so it does not bend the plate when i put the screws to it.

A little more fab work then i can test it out

Im going to bolt down the middle two cylinders then heat the balls off the ends, im hoping to bend down the ends to line the exauste ports up again.

[MaTTSuN]

well i got it all done, with a a lot of heat and a little welding and some drilling she is all sealed up again on my 280

after heating and "bending" the holes seemed a little off still so i drilled out the three hole where the center two cylinders are

that gave me more wiggle room and "sealed" the deal