I blew the manifold to turbo gasket twice this year while out on track. Using standard, not inconel hardware which I know is part of the problem. I want to fix it one more time, properly. Should I...

1 - Replace the gasket and add inconel
2 - Install inconel with no gasket
3 - Resurface turbo/manifold flat and add inconel with no gasket

I know a lot of you are running gasket-less. How flat do the flanges need to be? I'd like to stick a feeler gauge under a straight edge on the turbo and if flat enough avoid the giant pain in the *** that is pulling a MSM turbo. Is a HD Racing combination square straight () enough for this measurement?

 

option 3 = win

as for the flat part: its either flat or its not. if its not, it will leak. lol

 

https://www.miataturbo.net/engine-pe...46/#post964971

 

I'll have to find a piece of glass and see how straight my 3/8 extension is. What's the biggest feeler gauge I should allow between the straight edge and flange? Do I need another option?

4 - Don't be a bitch and pull that **** already

 

Oh, option 4 definitely.

No need for the extension straight option on a turbo/manifold, it's small enough you can get a straight edge like the one you listed to work. The extension is for a bigger surface, like your block.

I'm not sure on which feeler gauge would be good to use, you'd think it wouldn't have to be as flat as a block, but I really don't know how sensitive it is to being out of flat.

 

if you machine it right you shouldn't be able to get any feeler gauge anywhere. it will be FLAT

 

Flat is .000". If it's not .000", it's not flat.

 

Thanks. Flat it is. I really wish you sold a M8x1.25 Inconel kit Savington. It's tight as-is and I'm not sure M10 nuts will fit.

 

I thought TSE offered an M8 kit as well. If not, FM does offer an M8 setup:

Flyin' Miata : Turbochargers : Parts and upgrades : Inconel 718 turbo stud
Flyin' Miata : Turbochargers : Parts and upgrades : Stage 8 locking turbo hardware(8mm)

If you can't get the m10 to work, those might do the trick (albeit not as stout as the m10 solution).

 

Just out of interest are you using the OE turbo brace that ties the turbo to the block?

 

Yep

 

That is one piece I still have to find for my MSM turbo swap. Is there any reason not to run that brace? I got the FM 8mm Inconel studs a while back and they appear to fit perfectly on the MSM hardware lenthwhise.

 

So you're suggesting he requires a ground surface on his manifold and turbo to create an adequate seal?

I'd bet $5 of monopoly money no one's ever done that on this forum.

 

My turbo to mani seal used a little wheel bearing grease as discussed in another thread from a few years back. It fill the minute gaps and turns to hard carbon as it warms up.

 

You owe me $5 or monopoly monies.

 

You've had your manifold and turbo professionally ground? Grats on the overkill.

 

On both of my turbo setups (old *** 300zx t25 & used HKS mani / Chinacharger & Flying miata cast mani) I was able to just bolt the turbo to manifold with no gaskets and had zero leaks. OP, have you tried just running it without a gasket?

 

make that 10
it was like 20 for the turbo and like 40 for the mani. really not that bad to have the piece of mind of overkill

 

Belt sanded is not .000 flat. .000 flat is ground like your crank shaft bearing surface. Except that's round obviously.

 

Machined=/=belt sanded