Hello!

Nice forum, im from chile!
Well, i have a Lo5 engine 2 bolts, speed pro l2256f .40 bore (9,8 to 1 i think), mild edelbrock cam, intake summit, carb edel 1406 custom headers, fully balanced (153 tooth flywheel) stock cams (now im gonna port it just a little).
It really works fine when it works (not super powerfull, but it revs fast, very fast up to 5500)

My problem is that i have blown head gasket 3 times (1500KM)... (im a little tired from changing the heavy heads )
I use victor reinz 1178vc (there are not more alternatives in my country, but i can get another from summit).

Well i think the assembly was right, cleaned the holes, heads shaved, new standart chevy bolts, head bolts to 25-45-65 Helical Sequence (info from http://www.torkspec.com/torkspecme.a...-5.7L-350ci-V8).

The gaskets blows when i push the pedal up to the radiator (heavy load too many times).

Any clues?
Maybe the gaskets are not the best for my app?

las time after the blows, i checked the torque and it was fine (before i removed the heads).

Im very lost!!

thanks
Chris

 

Im assuming these are iron heads?

When you had them off did you have a machine shop magnaflux them to check for cracks? They cant always be seen with the naked eye

 

hello!
Yes, iron heads, not magnaflux, but one time was the right head and then the left head, so i believe that is not a crack. one head cracked...can be...but both? I dont believe i have so bad luck...
The only machinist that i know that magnafluxes its very very expensive. (%#" too much!)
Its easier to get some other heads... i fact im trying to get some vortecs! (the search continues)
thanks
C

 

Exactly where do they blow?

 

Could be lots of things. Low fuel PSI or to much timing. Cracked/warped, head/block...

 

one time between cyl 6-8, next time cyl 5-7.
maybe advance as sugested?

saludos
Chris

 

mmhhh. im going to deck the block and the heads.
Better to be safe...

thanks
C

 

i would bring the heads to a machine shop and make sure they are not warped or cracked. also, don't reuse the old head bolts, they tend to stretch after going in and out a few times. and for added security, go with head stud's, they tend to be stronger.

that said checking everything else wouldn't hurt.

 

im bringing the block and heads to the machine shop asap...
thanks
C