85.5mm 01 Block and 85.5mm 11.5:1 Supertechs
 

I was having this built to go Rotrex, but the block wall on the # 4 chamber is a tiny bit to thin to go FI. This will make an AWESOME NA motor. For those who are thinking of copying Savingtons rental, this can be a great starting point for a badass NA motor. Of course race gas will necessary for a safe tune on this CR.

The block and pistons are at Renkafer's shop in NorCal. As of now it's just a bare block and pistons. No Oil pan/Oil pump, rods, bearings, etc. The piston wall clearance is a bit tight, it will need to be bored out a bit more.

Quote from Savington regarding the Clearances "our engine builder measured the wall clearances on the existing 11.5:1 pistons and they are too tight - 0.0022". Supertech recommends a minimum of 0.0028."

Pistons with rings. Installed, never ran. $400 shipped.

Bare block bored to 85.5mm $200+ship.

Package deal $500+ship.

Email is best. My screen name at g mail dot com.

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You do not need race gas for that compression ratio.

I would assume depending on the type of head gasket used the compression would raise a bit .

And if i recall anything over 11:1 CP its recommended to run atleast 101 if you can find it . 11.5:1 CP + race gas + good tune = bad ass setup.

OP can you give me more info on the problem with the wall thickness . This is a little higher CP then i was planning on going but i might be interested in the block.

These would be tits in a turbo'd motor. hmmmmmmm

We (Savington and I) thought this would be a great setup for a kraftwerks blower that I'm working towards, IF the car lived on E85. I don't have any E85 stations around my home, and my car won't be a dedicated track car, so this didn't work for me.

https://www.miataturbo.net/engine-performance-56/11-5-1-e85-kraftwerks-53037/

We got another block and went 84mm and a 10:1 CR, the car will be street driven on California 91, and tracked on race gas.

These pistons could be milled a bit to get the CR of your choice.

Oh, I also have a Mahura HG that works with the 85.5 bore. I will throw it in if someone buys the whole deal. Otherwise $100.

Bump

Bump.

Shipping should be around $100 to the lower fifty.

Oh god, that would be a fun NA setup.

Seeing/hearing of these rotrex builds makes me happy! Thats going to be my next undertaking!

.0022 is not too tight.

Forgive me, but I'll be following the minimum Supertech provides and not the pseudo-wisdom of the internet. Supertech's documentations requests that the minimum wall clearance stays above .00236". Therefore, .0022" is too tight, despite whatever you may think or whatever someone else may have told you.

I'm not talking about the psuedo wisdom of the internet, rather multiple local engine builders who have been building race winning motors long before I was alive. Supertech's alloy is nothing special and can be treated like any other 4032 piston. I'm not arguing that .002 is not tight, it is.

Block sold.

Pistons still available.

Bump

Someone must want a high strung NA motor.