Master Jedi W8

[engled]

[c-evoVIII]

Wahahahahha!!!

[slowautoxr]

Is that an impact without an air line?? The force is strong indeed.

[TouringBubble]

I think that's the coolant inlet.

[Chuck Baader]

The real question is why is the motor out again???

[JohnW8]

The real question is why is the motor out again???

Loss of compression on cylinder #1 & #4. 10% loss on Leakdown test on #1 & #4. Spark plug on #4 was black and oily. You can hear the air blowing past the rings and through the crankcase. Next stop PSI for diagnosing why the rings aren't sealing and the recurring oil pressure issue. 40psi at 6000rpm. Better than last year of 20 psi at 6000 but still too low.

I want to see if it would be wise to just get a new short block... this one has bad mojo.

After that, maybe a saws-all and some goggles.

[Chuck Baader]

John....race car...build the motor correctly....40 over...forged pistons....etc. You'll save money in the long run. Chuck

[JohnW8]

John....race car...build the motor correctly....40 over...forged pistons....etc. You'll save money in the long run. Chuck

So bigger more expensive custom pistons will allow the rings to seal and make the oil pressure right???

[Chuck Baader]

Absolutely not....but do not use used pistons with a rehone. Fresh lasts. Clearances, clearances, clearances...you can't get there with a half ass build. CB

[JohnW8]

Absolutely not....but do not use used pistons with a rehone. Fresh lasts. Clearances, clearances, clearances...you can't get there with a half ass build. CB

This was a fresh build from PSI
.20 over pistons, biggest Mazda sells.

[Chuck Baader]

I said forged...there are several manufacturers that make for Miate. If you are going to build a race motor, do it right to the limit of the rules. CB

[JohnW8]

I feel like we are having 2 separate conversations. If the rings won't seal on .20 over cast Mazda Pistons then spending $700-800 buck for forged .40 over won't make a bit of difference other than saying in the paddock "See all that smoke? That's rolling off some custom forged pistons right there. Ain't it purty smoke."

I need to find out what is causing the issue before I spend a dime on a .40 over engine. Is it the clearances, material or is it something in the Megasquirt? Detonation? bad gas? Did this block have some fancy SM mojo done to it and screw up the oiling. I've got a 1.8L spare block I may just drop in the car for giggles depending on what the engine guy has to say.

[kilgojr]

WHAT DID YOU SAY JOHN, I WASN'T LISTENING. I WAS BANGING MY HEAD TO THESE MAD JAMS BRO.

[Chuck Baader]

Considering the history of the block I would not assume anything.

Detonation will show itself on the edges of the top of the pistons. Easily seen. Bad gas...we all have that especially when we get older

Albert should be able to find the cause of the problem.

Assume you used new rings on the rehoned cylinder? Should seat if the cylinders are ROUND!!! Probably not the case!!! And no ring will seat in an egg shaped cylinder. That is why I bore every motor I build. And my break in consists of running the motor at 2500rpm to 180 degrees, letting cool, then retorqueing the head studs. After that it goes to the dyno then the track. I can hear the rings seat in that 20 minutes or so it takes the motor to reach temp. Chuck

[JohnW8]

Considering the history of the block I would not assume anything.

Detonation will show itself on the edges of the top of the pistons. Easily seen. Bad gas...we all have that especially when we get older

Albert should be able to find the cause of the problem.

Assume you used new rings on the rehoned cylinder? Should seat if the cylinders are ROUND!!! Probably not the case!!! And no ring will seat in an egg shaped cylinder. That is why I bore every motor I build. And my break in consists of running the motor at 2500rpm to 180 degrees, letting cool, then retorqueing the head studs. After that it goes to the dyno then the track. I can hear the rings seat in that 20 minutes or so it takes the motor to reach temp. Chuck

We'll know hopefully tomorrow. I'm taking the engine, if that what you want to call it, to the shop.