I think I hurt it

[RT K_line]

I came out to a no prep test and tune and made a few runs. Las run sounded off when I shifted so I let off and coasted to the end. Checked it in the pits and the vacuum gauge is jump all over. I think I broke a spring or something. No smoke or oil anywhere but runs rough. Waiting for my wife to bring the truck.

 

[malex]

I came out to a no prep test and tune and made a few runs. Las run sounded off when I shifted so I let off and coasted to the end. Checked it in the pits and the vacuum gauge is jump all over. I think I broke a spring or something. No smoke or oil anywhere but runs rough. Waiting for my wife to bring the truck.

Oh that sucks. Tough break. Time to get those valve covers off and take a look.

 

[Mike67]

Hoping for the best Ken...

 

[RT K_line]

I'm glad I made this tow bar for just this type of situation and to get me home safely. 2 other cars had to be left there at the track because of broken axles. A subaru and a newer camaro.

 

[RT K_line]

I got lucky so to speak, the piston looks intact with just a small ding above the valve pocket. Found 2 other retainers about to fail.

 

[malex]

I got lucky so to speak, the piston looks intact with just a small ding above the valve pocket. Found 2 other retainers about to fail.

View attachment 549914 View attachment 549915

RT glad you came away with very minor damage. A little work, some new parts and your off to the races again. Are you just pulling the one head or both and touching up the valves / checking the springs while you're most of the way into it?

 

[RT K_line]

RT glad you came away with very minor damage. A little work, some new parts and your off to the races again. Are you just pulling the one head or both and touching up the valves / checking the springs while you're most of the way into it?

I'm going to pull both heads. I have a set of 906s I had done for this engine but bought the Eddy's. They need to be surfaced now from sitting so long in the south Texas humidity. I'll swap springs and I have a member her going to sell me some titanium retainers. I've been wanting tO do some porting to these and open up the push rod holes. The 906' have been heavily ported and I would like to see if the car runs better with no other changes.

 

[RT K_line]

906s installed and running great. Will check compression next.

 

[RT K_line]

Compression test on the 5 easiest cylinders including the affected one showed all within 8psi and highest at 130 psi. Without any cam info its looking good. I lost the cam card. Next will be some track time to see how the heads perform.

 

[Dibbons]

I could not make out the damage to the retainer in the foto. Is it a hairline crack? Did a valve kiss the piston somehow? Thank you.

 

[RT K_line]

I could not make out the damage to the retainer in the foto. Is it a hairline crack? Did a valve kiss the piston somehow? Thank you.

In post #4 I show the head with a retainer missing, the other pics show cracks on other retainers. I found 3 cracked half way through and one in half causing the valve to hit the piston and bend. No major damage jut knocked the carbon off. I put a set of 906s on I originally built for the engine at the time.

 

[RT K_line]

I could not make out the damage to the retainer in the foto. Is it a hairline crack? Did a valve kiss the piston somehow? Thank you.

In post #4 I show the head with a retainer missing, the other pics show cracks on other retainers. I found 3 cracked half way through and one in half causing the valve to hit the piston and bend. No major damage jut knocked the carbon off. I put a set of 906s on I originally built for the engine at the time.