Structural Valve Cover on an RF95

[Rick Iverson]

Gents;

Has anyone used an ICP or reasonable facsimile valve cover to stiffen the chassis, midyear Van Diemen?

[Neil_Roberts]

After a few unpleasant experiences, I learned that feeding chassis loads through an engine that was not designed for them is an invitation to disaster. Reliability and power both benefit from engine installations that are structurally gentle on the engine.

[Rick Kirchner]

I would argue that the 98 VD and making the engine a semi-stressed member was what got the pinto its bad reputation and the push for the zetec.

[Lotus7]

Our RF95 is long gone, but don't I remember it as already having a reasonably-triangulated structure over the engine and down to the bellhousing ? Or was that 94? 93?

[DanW]

Our RF95 is long gone, but don't I remember it as already having a reasonably-triangulated structure over the engine and down to the bellhousing ? Or was that 94? 93?

I believe the brace was a popular mod and cured the terminal push.

[Westroc]

Our experience was not with a VD chassis BUT is applicable. We tied a billet 1 inch thick plate on top of the structural V/C and fastened it to the main rollbar by 4 bolts. 2 each side. The thinking being it would at least be better. Well not so much. All of a sudden we start having valve cover seal issues. I thought about was it poor install or was something really bad happening.. One time I found 2 of the allen head bolt heads sheered right the hell off. Yeah something really bad was happening. What was happening was the rest of the engine was flexing, moving underneath the cover. Not something I felt in the highspeed corners but medium. It had both understeer then major oversteer in the same corner. Not one lap compared to another but the SAME corner. It makes the driving pretty damn exciting. We tried 4 different bar combinations along the sides which made it better. Not good enough but it was way less exciting. I will say this definitively. If you depend on just the 2 or 3 bolts to the oil pan you are in for a bad time. No chance it's good enough by itself. JIm.

[Rick Kirchner]

94/5/6/7 had a reasonably well triangulated structure. That said, there are two rivets in the pan bear the farthest point aft on the right, that pop off every now and then.

90/1/2//3 had a couple of variants of less triangulation, and folks often added an additional bar with heims on the ends.

I'd think that if you wanted to tie in the 94-97 to the valve cover there would have to be a couple of things done:

The front mount is the head, and there are viscoelsatic mounts at the frame. As you deck the block and skim the head the head's not where it should be any more. Who knows what VD designed to....

You really need to figure out there the bottom of the motor needs to be WRT the gearbox adapter centerline, and re-do the bottom of the chassis there, mount a late model pan with the front mount at the bottom.

then you make a couple of billet mounts that pick up the block at the upper mounting points and go to where the current mounts are on the frame. A bit of a challenging 3d puzzle.

Now you have the head floating, the block and pan stiffening the back of the chassis, and you can make the mount for the valve cover.

And then you're going to need shims because the distance from the top of the VC to your frame mount will vary with every engine. Then there's the tolerances in the frame spuds at the back, the gearbox adapter, yada, yada, yada....