MyE28.com

Looks like I've done it again. Compression test shows 30# on #6, blowby is blowing oil out from oil fill cap. Looking for recommendations on replacement pistons for an 84/m106 (basically an m30b34).
tia

CP Carrillo and JP offers custom pistons

Available from VAC Motorsports

Thanks, I checked them out. I'm not sure what I've got yet, until I pull it out, and apart. I suspect broken ring lands. It's hard to want to spend a grand or more on pistons, especially on such and old design motor. If it's pistons I may consider a whole different driveline, maybe LS. Of course, that opens up a whole nother can o worms.

KEEP THE BIG 6 ALIVE!

Hey Marc,

I am curious about the results of your autopsy.

What are you planning to do next.

I've been too busy to begin pulling the motor. I don't want to start the project until I can really have the time to get it done. So I've actual got three problems now.
the head gasket, or cracked something coolant issue (currently holding with blue devil h/g sealant.)
the low compression, blowby in #6.
the 60-2 vr setup with my ms2 (breaking up at 4500 rpm)
I still try to drive it a little, and iIm trying to sort out the vr signal. I may go back to the dizzy pickup. I really thought the 60-2 was going to be the better setup.
It drives surprisingly well for a car with so many, major issues so for now it's in limbo.

Upon autopsy you will know if cylinders need a boring job or not.

I'd start looking for a spare M30 block.

I would refresh the block and gap the rings.Ideally have the ridge removed and keep the whole thing stock,maybe even used piston rings.
Goetze headgasket,stock head bolts.O-rings if you feel so.

Rock that M30 on low boost.Put the M106 on the stand.

There is a cheap forged piston option but it is 94mm Let's not get carried away just yet...

LS is not cheap nor that easy.

I think it's a good time guys to tell Marc we love him.

Get that spare M30 and give it the minimum preparation.

I am about to start my M106 build.Let's be friend

Thanks man! Hopefully another month or so, and I'll be free to tear it down.

Here are the specs for the JE forged pistons I used in my M30 that is running around 16 psi right now.

great info ! thanks