Should there be a Cam Thrust Plate on a 66 427???

[Joe L.]

Re: Should there be a Cam Thrust Plate on a 66 427???

chevy 6 cylinder engines used gear drive cam with a thrust plate. check the part number and see if the 6 cylinder used the same thrust plate

clem------



From what I can tell, the 6 cylinder thrust plate was either GM #3707916 or 2454008. Unfortunately, I don't have the part number for the big block plate since I don't have HD truck parts info. However, based on the info you provided earlier in this thread, the big block thrust plate/bearing looks like it was GM #3864862.

[Ray K.]

Re: Should there be a Cam Thrust Plate on a 66 427???

All----

The Heavy Duty truck 366 and 427 engines did indeed use a gear drive camshaft in those applications which required a thrust bearing. There is one camshaft listed for L-88 engines which was a gear drive cam -- part #3925533 and there is a notation in the H-D part catalog that it requires a thrust bearing #3887871

Ray

[Clem Z.]

Re: Should there be a Cam Thrust Plate on a 66 427???

a lot of performance parts are made from HD truck parts like the deep sump oil pan we discussed on this site before.

[Joe L.]

Re: Should there be a Cam Thrust Plate on a 66 427???

All----

The Heavy Duty truck 366 and 427 engines did indeed use a gear drive camshaft in those applications which required a thrust bearing. There is one camshaft listed for L-88 engines which was a gear drive cam -- part #3925533 and there is a notation in the H-D part catalog that it requires a thrust bearing #3887871

Ray

Ray-----


The gear drive cam for L-88 was never used on a PRODUCTION engine. It was strictly a SERVICE-only piece.

[Domenic T.]

Re: Should there be a Cam Thrust Plate on a 66 427???

For what it' worth. When I got my 67 443/427 it was bastardized with headers and a aftermarket gear drive that didn't have a thrust plate, only a teflon button to keep it from pounding the aluminum timing cover.

When I took the engine apart the gear tore up the casting and I had to machine the block and make a thrust plate for the new cam (with a double roller chain) to fill the worn area.

The gear set up is in a 454 now that is on the shelf. It does not have a thrust plate, only the teflon button.

So if I understand things, I will need to add a thrust plate or just get rid of the gears?

DOM

[Clem Z.]

Re: Should there be a Cam Thrust Plate on a 66 427???

For what it' worth. When I got my 67 443/427 it was bastardized with headers and a aftermarket gear drive that didn't have a thrust plate, only a teflon button to keep it from pounding the aluminum timing cover.

When I took the engine apart the gear tore up the casting and I had to machine the block and make a thrust plate for the new cam (with a double roller chain) to fill the worn area.

The gear set up is in a 454 now that is on the shelf. It does not have a thrust plate, only the teflon button.

So if I understand things, I will need to add a thrust plate or just get rid of the gears?

DOM

straight cut gears put no reward thrust on the cam to wear the block but helical cut gear do so you need a thrust plate. the pressure that pulls the cam in to the block is caused by the valve spring pressure on the lifters so stock springs should not cause a problem. heavy springs like after market roller cam springs will cause the gear to wear in to the block because of the added pressure and you need a thrust plate

[Domenic T.]

Re: Should there be a Cam Thrust Plate on a 66 427???

Clem,

Thanks, the gears are the loud straight cut.

You saved me some time, I was going to remove the gears.

DOM

[Clem Z.]

Re: Should there be a Cam Thrust Plate on a 66 427???

Clem,

Thanks, the gears are the loud straight cut.

You saved me some time, I was going to remove the gears.

DOM

if this is the setup with the "dog bone" holding the 2 idler gears check it for cracks as i have seen some break in two. this too late for you but i always drill a .032/.040 hole thru the block thrust area into the oil passage to get more oil to the block/gear interface