jdnca1,

I believe you are right about the spring pressure being too high. You may want to check with Comp. Cams Tech dept. They make a roller lifter that is advertised for use in "street" driven roller motors. They are supose to have oiling holes that spray directly on the needle bearings to keep them cool and last longer.

We have a local drag racer that uses these lifters, and drives his car on the street. Last time we talked about it, he said he had over 900 street miles on them and 72 passes @ the track, keeping a good eye on valve lash. He has a beautifull '55 Chevy(#3600), runs a 502'' BB, and runs 10.0's all motor. All the information he told me about his engine set up is second hand, so I would recomend calling Comp. to make sure exactly what they recomend. They may have something you can use.

I have read an article that included information about Jesels lifters. The reasons they are supose to be so good is.....

*They have larger diameter bodies, (have to have block machined to accept them)
*They have bigger rollers (supose to cut down on the load on the needle bearings)
*You can use a cam with a less aggressive profile and still achieve the same durations(easier on the lifter itself)
*The lifters weigh less(shorter than regular roller lifters, and materials),but you have to have the lifter bores slotted to keep them in line(they have no bars to align them).

If you were building an engine from the ground up and didn't mind spending the extra $'s for the lifters and machine work, in theory they should last longer than others on the market.

I would give Comp. Cams a call and see what the tech's have to tell you, they may have something you can use.

Good Luck :)

Makino;

The comp lifters with the oil grooves are the ones that just failed...only 7 hrs on them. My previous set was the std. comp lifter which lasted about 35 hrs. You are correct in there being too much spring though, however with the roller lifter valve train I ran I needed at least 250# on the seat and 700# opening to stay away from valve float through 7000rpm. (the triple spring set-up was good through 8500) Everything you've stated about the Jesels are true, I'm just saying my buddy that ran them is his 940hp NA single carbed ford 360 small block didn't see them last any longer than a std lifter....Now we'll keep in mind he turns 10,400rpm with over 1" of lift and runs 380# on the seat. Just a little more "radical" than our boat set-ups:rolleyes:

JB;
I made 900HP at 6600 naturally aspirated on pump gas....a pick-up of 40hp from the old cam with 10 degrees less duration at 6000. Most 500" blower motors won't make that kind of power. Lately I've been breaking some parts, now I'm just trying something else that "might" live. I know a hydralic roller set-up will work, but really hate to give up 100HP. There is no-one harder on parts than sprint car guys and these radius lifters are living in their motors so we'll see...it should be interesting.

I assume that you are running a mechanical lifter. Would running one of the rev kits help? These are the ones that move a spring from the head to the lifter.

I run a 540 in my drag car and occasionly street drive it. My cam and springs are similiar to yours (290, 312 @50 885, 805 on a 114 center line. Springs are 350 at the seat and 1010 open. I originally had several Comp Cam lifter failures. I switched to Beileve It Or Not... Iskies.

No problems since. 250 passes and about 1000 street miles

I used to manage a speed shop and sold lots of these lifters and never heard of a failure.

Very similiar design as Jesel but a lot cheaper and don't require additional machining ( $ 475.00 Set)

302SR1;

I've been hearing the same thing from several people about the Iskies, could be something there. By the way that is a THUMPER you have in your 540..it has to sound pretty good, where do you idle 1500??

From what I understand, Roller lifter failures in boating and street occur from lots of low RPM operation (long idle zones, traffic lights, etc...). The lifter axle does not get proper oiling and the axle fails.

Iskies actually have a small bearing race on the axle itself. eliminating the need for as much oil during idle.

I think Isky might be on to something because like I said above, I would have at least a half a doze failures with other brands with the time I have on the Iskies.

With all due respect and aside from all this other talk about other lifter manufacturers, I am still very intrested in how the Schubeck radius lifters perform and endure in the marine engine environment. If these radius lifters work, Joe Schubeck is going to really have something HOT! You can check out his stuff at: www.Schubeckracing.com