Don Terrill’s Speed-Talk

I'm almost ready to start assembly on my SBM race motor.

The normal deal is to "tube" the right side oil gallery that feeds the lifters then drill out that copper tube so you still have oil to the crankshaft.

These engines leak oil around the lifters and the bores themselves are short so you may expose the oil band when using a high lift cam.

Bushing the lifter bores is best but this oil tube deal works well, too.

You wind up with splash and drip oiling to the lifters. The rocker shafts are fed from the oil gallery in the block and heads. No pushrod oiling.

The lifters I have are solids with no oil feeds or oil band.

I don't think an EDM drilled lifter will do any good...opinions?

The best option is to bush the lifter bores, and pressure feed oil to the bushed lifter bores. Run the AMC lifter(#998), with the EDM'd oil hole in the lifter face.
If you're worried about too much oil passing thru the pushrods, run pushrods with solid tips.

The "Tube" deal scares the hell out of me. With no pressurized oil to the lifter bores, and only relying on oil draining around the lifter, there's a potential for problems.
The more aggressive the cam, the higher the spring rate, and the higher the rocker ratio, the more side loading the lifter will see.
At some point, the pressures will be high enough, where the oil draining around the lifter won't be enough to keep the lifter spinning. as soon as a lifter stops spinning, you have cam failure.

When Chrysler cam out with the "R" block, we did quite a few for circle track racing, and we ran the EDM'd AMC lifter in all of them.

Bushing the lifter bores isn't cheep, but it also allows you to true the lifter bores, and that also increases reliability.

I'm sure you know that tubing the block was Mopar's answer to keeping the bottom end alive in endurance engines. They even sold the jig used to drill the new holes in the tube to keep the oil flowing to the right places.

Can't be any worse than what happened to front crank journal in this engine when it was run cold with thick oil.

I'll do my best to keep that new Jones cam in good condition. If it blows up I'll tell everyone it was a Comp Cam....

Update......

Since my machinist still hasn't finished my block and heads I have been thinking about oiling system mods.

Instead of relying solely on splash/drip oiling for the lifters I will still tube the right oil gallery but I think I will drill small holes in the copper tube to provide lifter oil....maybe 1/8"?

In addition, to keep a steady supply of oil to the main bearings, I will tap into the pressure oil line coming from the oil supply line to my Accusump, run it thru the rear China wall, and tap into the front of the block into the gallery that feeds the front main.

That's a common deal on these SBM engines. It should stop any leaks from the lifter bores while still supplying sufficient oil to the lifters along with crankshaft splash and gravity feed from the heads.

This way the main bearing feed will be direct without having to share oil with the lifters.

Comments?

Krooser wrote: ↑Sun Jun 28, 2020 11:12 am Update......

Since my machinist still hasn't finished my block and heads I have been thinking about oiling system mods.

Instead of relying solely on splash/drip oiling for the lifters I will still tube the right oil gallery but I think I will drill small holes in the copper tube to provide lifter oil....maybe 1/8"?

In addition, to keep a steady supply of oil to the main bearings, I will tap into the pressure oil line coming from the oil supply line to my Accusump, run it thru the rear China wall, and tap into the front of the block into the gallery that feeds the front main.

That's a common deal on these SBM engines. It should stop any leaks from the lifter bores while still supplying sufficient oil to the lifters along with crankshaft splash and gravity feed from the heads.

This way the main bearing feed will be direct without having to share oil with the lifters.

Comments?

Are you suggesting one .125" hole per lifter? That's an awful lot of oil. Probably need to be around .020" hole size per lifter

Charliesauto wrote: ↑Sun Jun 28, 2020 6:11 pm

Krooser wrote: ↑Sun Jun 28, 2020 11:12 am Update......

Since my machinist still hasn't finished my block and heads I have been thinking about oiling system mods.

Instead of relying solely on splash/drip oiling for the lifters I will still tube the right oil gallery but I think I will drill small holes in the copper tube to provide lifter oil....maybe 1/8"?

In addition, to keep a steady supply of oil to the main bearings, I will tap into the pressure oil line coming from the oil supply line to my Accusump, run it thru the rear China wall, and tap into the front of the block into the gallery that feeds the front main.

That's a common deal on these SBM engines. It should stop any leaks from the lifter bores while still supplying sufficient oil to the lifters along with crankshaft splash and gravity feed from the heads.

This way the main bearing feed will be direct without having to share oil with the lifters.

Comments?

Are you suggesting one .125" hole per lifter? That's an awful lot of oil. Probably need to be around .020" hole size per lifter

The stock supply is huge hence the need to tube the block.

Im no hydraulic engineer but you may be right...i know a slight increase in orifice size allows much highr oil flow. You figure is likely better. The oem hole is about 3/8”.

Here's a shot of the tubed lifter bores. You can see the copper tube as well as the OEM oiling holes. They lose a ton of oil on their way to the crank journals.

I figure I can drill from the lifter valley, thru the lifter bore then plug the hole in the valley.

Pic is not my block BTW.

you could groove the lifter bores from the oil passage to the bottom but would still have to have oil to the lifters
you do the side of the lifter bore on the leading edge- opening side
7200 rpm and no time to do the lifter bores?
just use the AMC edm lifters and check your clerance
hv pump hard shaft
I'd run oil through the pushrods heavy wall 3/8 or 7/16 dual taper
did you find springs?

I have been grooving lifters for 30+ years. Use a Dremel with a 1" cutting wheel, 0.020-0.025" wide & grind the groove. Start at the oil band & go to withing 1/8" of the lifter base, not critical. Use 180 emery on the groove to smooth any high spots.

I use a mag bed plate grinder and a V block to make the chevy V6 style flats but it gives a lawn sprinkler effect- all around where it's needed
better is grooving the lifter bore for hyd and edm for solids
and no tiny tiny edm either
some use two holes, some offset slightly
jury is still out on thatI appreciate the comment on cooling
then there is nitriding and coating

Right now I have Crower/Comp style lifters w/o an oil band. No chance to expose a non existant oil band in those short lifter bores.

I'm leaning toward a small hole in the lifter gallery tube. There's a Mopar pavement racer I've talked to and that's how he does it.

I know tubing the block makes Mike Jones nervous... I told Mike if the cam goes bad I'll tell everyone it was a Comp grind.

As far as springs go the Crowers you mentioned in a PM on fabo may be the ticket. Waiting to hear from dart19666...the LS7 spring would be good too

FWIW, my vote is for doing it the way Mike described. He didn't just fall off a turnip truck yesterday. No need to risk wiping a cam lobe especially given all the recent oil related cam failures.

Just sayin'......

Harry

MadBill wrote: ↑Tue Jun 30, 2020 10:25 pm https://www.tdotperformance.ca/comp-cam ... tYQAvD_BwE

Says it’s for .842/.875 lifters. Doesn’t say if you can get it for .904 lifters.

ClassAct wrote: ↑Wed Jul 01, 2020 8:57 am

MadBill wrote: ↑Tue Jun 30, 2020 10:25 pm https://www.tdotperformance.ca/comp-cam ... tYQAvD_BwE

Says it’s for .842/.875 lifters. Doesn’t say if you can get it for .904 lifters.

That is a screaming deal....think they will ship to the US without a huge ship fee??
Both Comp and Powerhouse get $150 for a single head version.

Comp Cams #5007 is the .904" version.