[mgarblik]

Original Ram Air V heads had no head gasket issues according to Mr. Beswick. There are two things going on here as mentioned. Excessive heat, (two exhaust valves side by side), and head stiffness, (aluminum heads). Our billet Ram Air V heads are running the same pair of head gaskets we started with in 2011. 1700+ degree exhaust temperatures. So even though billets, that tells me separating the exhaust valves is a GREAT idea in a race engine. If we were running the same style head with conventional valve layout, I think we would have some gasket issues. I have no proof of this however.

[Scott Roberts]

Originally Posted by John Langer

There is no clamping issue. There is no softness issue. There is a heat issue. Remove the heat, remove the problem. It's that simple. Using the insert by itself will not resolve the issue.

You're wrong......

[[email protected]]

Originally Posted by Hooter

A guy in our nostalgia group has had a similar experience running NA only. Wonder if a good heat treat on the heads will help fix this issue.

This set indented from the head gasket. Imo thats not a heat issue

[John Langer]

Originally Posted by Scott Roberts

You're wrong......

Care to elaborate with first hand experience? The problem only exists between the center cylinders. The outside holes have the relatively same bolt pattern but the issues does not exist there. If it were a clamping issue it would happen between each hole. If it were a softness issue, is would happen on each hole. The centers is the only location where the exhaust valves(heat) are next to each other. My current tigers heads, we put the insert between the centers. We blew out the gaskets within 6 pulls on the dyno. Added the water mod and have gone 37 runs before pulling the heads to inspect. No issue. We got rid of the heat, we reduced the problem.

[John Langer]

I've seen it 50 times. Loose 20psi cranking compression on the centers, pull the head. Gasket has blow by on both sides of the gasket in the center. Head looks like you smashed it with a ball peen hammer in the center creating a dent. Machine .004-.013 off the deck and put it back together. 5-35 passes later, repeat process.

[Elarson]

John's experience exactly parallels what happens to the head at the hot spot.

1) the head grows more and has nowhere to go but to "hump up" between bolts
2). The modulus of elasticity of aluminum goes down, making the head more flexible (reducing clamp load)
3) the yield strength of aluminum drops which increases the chances of permanent distortion, indenting, etc.

We're big fans of the divorced ports of the RA5. But when we were using conventional layout heads, the Tigers sealed better than e-heads, FWIW.

Eric

[Scott Roberts]

Originally Posted by John Langer

Care to elaborate with first hand experience? The problem only exists between the center cylinders. The outside holes have the relatively same bolt pattern but the issues does not exist there. If it were a clamping issue it would happen between each hole. If it were a softness issue, is would happen on each hole. The centers is the only location where the exhaust valves(heat) are next to each other. My current tigers heads, we put the insert between the centers. We blew out the gaskets within 6 pulls on the dyno. Added the water mod and have gone 37 runs before pulling the heads to inspect. No issue. We got rid of the heat, we reduced the problem.

I have several years worth of personal experience with tigers and boost.... do you? I had issues other than the center exhaust ports...I had some of the first ones... first thing we did was move the intake valve .050 and interlock the seat...your welcome... maybe the castings have gotten better...I'm sure they have... AP cares about its customers...No need to expound....carry on.