External oil pumps/roller cams/bronze gears

[SFfiredog]

Originally posted by PatBuckley


Thanks Mike -

I think you will agree that roller cams (including lifters, springs, retainers, seats) have come a long way in the last 10 years - it used to be that a roller was a for sure a bad thing on a street car that was driven around with lots of idling and low rpm use - not that todays rollers should be driven like an old lady but they are more tolerant of it.

I am pretty comfortable with my choice based on the cars use, how frequently I adjust valves, change the oil, and generally keep an eye on things as well as the fact that I have a dry sump.

I suspect your comment about building an engine that would only give up 20 hp while using a flat tappet cam was kind of like saying that you could build a 300 cubic inch engine that would make almost as much hp as a 400 cubic inch engine - true if you spec'ed the hell out of the 300 incher and kept the 400 incher pretty tame.......is that what you were saying?

Take care,

Pat

PS - Turk and I need some of those neat exhaust clamps - I recall you saying you had a line on them...do you still?

Pat,
You got it! It's like shooting a guy in the head with a 9mm at point blank or with a .45 ACP at point blank. They are both gonna make a big hole, just like a street engine. Now, if you shoot Jamo in the head with a 9mm (not that anyone would EVER do that )
It might bounce off, so you would need to step up to the .45 ACP,
just like a race engine
You are a meticulous gear head like myself and you do very nice and competent work so I have no doubt that you will have no problems with the maintenance required of a roller cam.
I am also sure you used top of the line components as well.
Your big advantage is the dry-sump. As you stated, there is next to no load on your distributor gear so it should last a very long time. Purchase a good on-engine valve spring tester and keep an eye on the seat pressures and also be very aware of changes in your valve lash during adustment. A gradual or sudden change in valve lash is the first sign a roller bearing is going away.
And, I'll bet that Jamo is not a wrench-head and would rather be driving his beautiful car instead of paying someone to work on it. That's why I figured he would be happier with a flat tappet.
Exhaust clamps like the ones you guys installed at Turk's are no problem. Just let me know the size and how many you need.
All the best,
--Mike