351W long rod very short life

[Guest]

[mmb]

It's not the piston, we have gone 9.60's with KB pistons in a 393 all motor.  12.1 compression 7200 rpm and it lasted years until a seat fell out of the head.

[ranchopower]

It's not the piston, we have gone 9.60's with KB pistons in a 393 all motor.  12.1 compression 7200 rpm and it lasted years until a seat fell out of the head.

OK I believe you 100%

But Im not sure what made number 4 cylinder a 4 inch hole at 6800 rpm
I think I should of not mixed a hyper piston with a gapless top ring.

I never burnt a plug in the engine either so I am a lil miffed

Javier

[scienceguy]

OK I believe you 100%

But Im not sure what made number 4 cylinder a 4 inch hole at 6800 rpm
I think I should of not mixed a hyper piston with a gapless top ring.

I never burnt a plug in the engine either so I am a lil miffed

Javier

The rings may act as 'gapless', but there is still a gap for expansion.  Study the rings, and you'll see it.  That gap should be plenty big for those pistons.

Good Luck!

[69 Merc]

Why not use forged instead of hyper pistons?

[ranchopower]

OK I believe you 100%

But Im not sure what made number 4 cylinder a 4 inch hole at 6800 rpm
I think I should of not mixed a hyper piston with a gapless top ring.

I never burnt a plug in the engine either so I am a lil miffed

Javier

The rings may act as 'gapless', but there is still a gap for expansion.  Study the rings, and you'll see it.  That gap should be plenty big for those pistons.

Good Luck!

I had to file fit the gapless ring, maybe that one was the tighest one?  That cylinder had the best cranking compression of 190 psi.
before I adjusted the valves hot.

I agree that the gapless still has to have the extra clearence added in, and I thought this would work well.
and it did till I killed it.

Javier

[turbo2256]

Could have been just a bad piston.
I suggest going with the light weight wrist pins

[BirdMan]

I would go with the larger ring gap's and get some extra clearance +.001 bearings as they were too tight.

[69 Merc]

Why not use forged instead of hyper pistons?

 

[351 windsor snake]

Why not use forged instead of hyper pistons?

 

If you read his previous posts regaurding his theories about reusing oil,I am sure you will find the answer.

[liljoe07]

[juiced coupe]

Why not use forged instead of hyper pistons?

 

If you read his previous posts regaurding his theories about reusing oil,I am sure you will find the answer.

Hey, my junk has hyper pistons! 

But I do change my oil. 

[My427stang]

Tune out to lunch 

I have not been able to come up with a conclusion as of now. Fact is the piston could not hold the pressure/heat, so my next tune will be colder plugs less total timing and a EGT in the dang car!
I am doing this with my buddy Jim so we try to make the best with a few dollars and a few ideas.
I build it and he helps wrench, but he owns the whole deal.
So far it has been fun even with this flesh wound 

Javier

So next time 34* total timing?   

That was with 20 intial timing @1000 rpm  and total 32 @ 4000 rpm

Maybe try 25 total next try

Javier

How did you limit timing to only 12 degrees mechanical?  Seems like classic detonation damage, could you have more advance than you think?

[ranchopower]

Why not use forged instead of hyper pistons?

 

If you read his previous posts regaurding his theories about reusing oil,I am sure you will find the answer.

the motor had only 50miles so how is ur post relavent?

Javier

[ranchopower]

              How did you limit timing to only 12 degrees mechanical?  Seems like classic detonation damage, could you have more advance than you think?
         

The car/engine was built by me and my buddy. I rather of had more control of the build but it is what it is.
The day I cranked up the motor, my buddy Jim took the car home. no timing no tune nothing!  I was pissed but I got paid and that was that.
A month goes by and I get calls, this aint right, this isnt working, hey I have to bring it to ya I cant make it run no more.
So I get the car back and the distributor MSD is FUBAR only had 3 cylinders firing.
So who knows what Jim and friends did???
I took a magnetic FORD pickup distributor and modified the centrifical advance myself to get 12 degrees, set it up with a timing light and the car came to life until I killed it.

Javier

[ranchopower]

Why not use forged instead of hyper pistons?

 

I had the pistons already from 2002 and my buddy Jim said what can we put together.
We always like to push the envelope as much as we can.
We have a new shortblock almost ready to assemble now with forged pistons.
I have a 435 almost ready too that has Hyperpistons so I will be sweating on that one, but I think I got a handle on it now.
You got any new pics of that ugly car I want to see more...
Javier