Blown head gasket
Turbo Mini Forums

Just blown head gasket. done 6500 miles. I don't drive it gently. has anyone any Idea of the cause. the gasket is AF 470 compression is 8.5 to1 ..8psimax boost.... been using the latest E10 fuel no additives. I checked the head for flatness and there was a slight warp and have had it skimmed.

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Is the engine surface flat? Studs torqued right?

you can do anything if you set your mind to it...
i rather blow it up winning than keep it together losing.

finish date set for project 1... march 2018

yes the block is flat. the studs were tight when I unbolted it so I presume they were right

also i dont have a bypass between head and pump. I am thinking of reinstating it

BK450 gasket, the head flatness is key, probably caused the blow.

'Where does the engine go?'

just collected the head from the engineers. He took 8 thou off it said it was dished in the middle the ends were flat after 1thou. Is the minispares copper GEG300 a good gasket?

too much advance ?

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

Most likely:

Not enough fuel
and/or
Too much ignition advance

In the 13's at last!.. Just

Could it be no1 getting too hot as there is no bypass to allow water flow around that pot causing detonation?

Unlikely. Mine failed in exactly the same way,due to warped head.

'Where does the engine go?'

you're basically saying multiple reasons.

You've admitted the head was not flat, 8 thou is a fair bit. Although was the irregularity in the same location it blew ?If so, then almost certain that is the cause

But as others said, maybe a little lean, too much timing...aka detonation and perhaps not clamped correctly.

That said, decades ago when I ran mine, far too often I had a ton of detonation and it never blew like that. It was always between cylinders every few thousand miles. It's also surprising how quick you can get at swapping out the gasket....without even lifting the head completely off in some instances lol

Edited by stevieturbo on 18th May, 2022.

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

That block looks like it needs decking did you measure the squish of each cylinder.
If you want to go bullet proof get a cometic head gasket or just stick to BK450,

More fuel looks like your running lean.

Own the day