The V8 Owners Forum -

ok im going to make my self sound stupid like i dont know what im trying to say, but ive thought for a while how to word this but just dont know how to put it....

well here goes... the early RV8's had cams that were designed to push them selves into the back of the block so no camshaft retainer was fitted.... you with me so far lol

and on the later engines they fitted a retainer to the front of the cam.....

.... so where the cams also designed differently so they didnt push into the back of the block?????


the reason im asking, ive just bought a new up-rated cam and im sure the front of it is cut more to allow for a retainer plate, so now im worried because my 3.9 is the realy early type that didnt have the retainer, so i dont no if the cam will try to push its self out of the block.....

if this will be a problem how easy will it be to sort out???

thanks

Hi
The early engines had a distributor that drove off the end of the camshaft. The action of the skew gear tended to push the cam backwards into the block, so no retaining plate.

The later engines were distributorless, so the need for the plate to hold the cam in place.

There are some cams on the market that have machined to take a retaining plate and also have a dizzy drive. These were intended for the "intermediate" engine that had both a dizzy and a retaining plate.

If you've got an engine with a dizzy , you do not need a retaining plate.

Regards
Jim

More accurately it's the load generated by the oil pump that provides enough thrust on the skew gear to locate the cam - not the load from distributor which is not high enough on its own. That is why the plate is still required on serp drive distributor/intermediate engines (which have the g-rotor pump) as well as serp non-distributor engines.

In all cases it's a good idea to fit the plate (with appropriate feature machined into the cam if it doesn't have it already) if you have the holes in your block to enable you to do it. It's even worth drill/tapping the holes if they're not there already.

Reduced chain wear, more accurate ignition timing etc is the result.

Russ