340 Winter Upgrade

[RUNCHARGER]

I wouldn't have taken it apart but good on you for catching the PV contact. I don't know how you guys get so lucky, I had that happen once and it broke a Hemi head and I had to sideline the car for a year and a half searching for another head (1981 and Hemi parts were hard to find). I broke it the same way you did, 7000RPM in high gear.

[cudabob496]

your car deserves an AFR meter

[Shane Kelley]

This is the plugs when I run my set tune up. This is with 72 mains and quality 100 octane fuel. Before I parked it I had bumped it up a couple times to 75 mains and garbage 92 fuel. That was a terrible combination. The last pic is with 75's and quality fuel.

[HP_Cuda]

135 mph on manual brakes sure would be alot of fun if you had to stop toute suite.

[Shane Kelley]

135 mph on manual brakes sure would be alot of fun if you had to stop toute suite.

Honestly the car stops on a dime. I have a small bore master cylinder with the large brakes and it works really good. That small bore takes less effort and pushes more pressure than the original large bore master cylinders.

[HP_Cuda]

That would be something to see...

135 mph on manual brakes sure would be alot of fun if you had to stop toute suite.

Honestly the car stops on a dime. I have a small bore master cylinder with the large brakes and it works really good. That small bore takes less effort and pushes more pressure than the original large bore master cylinders.

[cudabob496]

135 mph on manual brakes sure would be alot of fun if you had to stop toute suite.

ya, I almost hit a toute suite once!

[MOPAR MITCH]

Nice winter upgrades!... heated garage?

[Shane Kelley]

Nice winter upgrades!... heated garage?

Yes.  I have heat and A/C in my shop. It's kind of a combo shop/man cave.

[1 Wild R/T]

Your piston to valve contact looks like the piston cutout is for a smaller valve... It didn't hit the bottom of the valve pocket, it hit the edge...

[Shane Kelley]

Your piston to valve contact looks like the piston cutout is for a smaller valve... It didn't hit the bottom of the valve pocket, it hit the edge...

Exactly. Probably some cheaper pistons of some sort. The good news is that it won't be run any harder than I have already run it. I'm going to dress these two pistons up and run it. I'm still under the impression that a couple valve springs must be weak. Otherwise all the pistons would be marked. IMO

[1 Wild R/T]

Your piston to valve contact looks like the piston cutout is for a smaller valve... It didn't hit the bottom of the valve pocket, it hit the edge...

Exactly. Probably some cheaper pistons of some sort. The good news is that it won't be run any harder than I have already run it. I'm going to dress these two pistons up and run it. I'm still under the impression that a couple valve springs must be weak. Otherwise all the pistons would be marked. IMO

[734406PK]

  Something else is wrong IMO.

[Shane Kelley]

Something else is wrong IMO.

Like what?  Other than piston manufacturing issue with the piston height or a bad rod bearing I can't think of anything else that would cause that to happen. No engine knocks and great oil pressure tells me rod bearings are probably good. The marks look pretty fresh also. Like it happened on the last big top end run before I parked it.

[RUNCHARGER]

We always try to hit them a bit harder Shane.