needle roller bearing ?

[33 fuel]

any hp gains in replacing cam bearings with roller bearings. I see this would help on restarting a motor [less drag ]looks like a standard mod.in prostock .Also if anyone has this done have you noticed any wear on cam .whats the life expectancy of the needle bearings thanks.

[Chris Uratchko]

If there are any hp gains it might be from less oiling requirements and the resultant windage.... other than that, there are no hp gains from one to the other as the result of friction.

[Jay Allen]

If there are any hp gains it might be from less oiling requirements and the resultant windage.... other than that, there are no hp gains from one to the other as the result of friction. Yep.......What CU said is dead nuts on the money in my book.

But what it does allow is for a bigger base circle on the cam and there is something to be said about that.

[Chris Uratchko]

Probably shouldn't end it there I suppose... as there are some reliability issues that come into play in this too.... but that is somewhat subjective as well.

I prefer roller bearings in almost everything.... but some folks won't touch them... :smt102

[33 fuel]

i just did a kb block i cut grooves front and back of bearing location to stop bearing moving {sir clip grooves} pro-mod blower motor lots of spring pressure. Cast blocks don't see any movement {yet } restarting seems noticably easier {street driven motors}.

[strlegal]

I've heard that high valve spring psi's can require the use roller bearings, due to tendencys to spin standard cam bearings on startup. Any truth to that?

Mike

[Chris Uratchko]

Well, I don't believe it will spin the bearings unless something out and out fails... I have run 1100 pounds of spring on a stock bearing(sbc)... the bearings were the coated bearings that come with Dart blocks.... they looked un-used upon teardown at the end of the year....

But, I have also seen plenty of folks hurt bearings with big pressure... I think a lot of it has to do with the oiling system, the clearances, and the tolerances in the block machining - Are the bores concentric...

Some big shops out there won't use a roller bearing because they don't trust them... some big shops out there won't use a slider bearing because they don't trust them.....

FLAVOR OF THE WEEK.

[Jay Allen]

I have customers running some real stupid pressures on a slider type bearing. It is my opinion that people do not check enough. Thenj when something fails, it just COULDN'T be their fault. It has to be the cam bearing or whatever it is that failed.

Kinda like a solid roller cam on the street. What a crock of donkey doo doo that is.

[steel town]

Sorry for high jacking this but what is the problem with roller cams on the steet Jay ?

[Jay Allen]

Sorry for high jacking this but what is the problem with roller cams on the steet Jay ?
Well, rumour has it that the excessive spring pressures will wear the lifters out. Match that with a lifter that doesn't oil and the valvetrain is FUBAR. And you have to set valves like at every red light.

Funny I have 6000 miles on mine just this summer. I guess I had better take the SR out and put a hyd roller in!

[chief67]

Well, rumour has it that the excessive spring pressures will wear the lifters out. Match that with a lifter that doesn't oil and the valvetrain is FUBAR. And you have to set valves like at every red light.

Funny I have 6000 miles on mine just this summer. I guess I had better take the SR out and put a hyd roller in!
I hear you there.Guess some people need to forget about what they read in all the magazines

[Rick_R]

....Kinda like a solid roller cam on the street. ....

I think the "myth" started a very long time ago and might have been true then, AS I remember very early solid rollers were plauged with many problems and thus shouldn't be used on the streets, hell you were sometimes lucky to get a couple of passes out of setup before you had to fix something (push rod, spring, rev kit). The science just wasn't where it needed to be on springs and lobes. The science is there now and a solid roller if properly designed can be used on the street. the problem is the "myth" still lives on, sorta like dodges don't start in the rain, That happened in the 1940's but it is still around too!

[steel town]

I was thinking you knew somthing I didn't cause I've ran my SR on the street for about 5 years

[Jay Allen]

the problem is the "myth" still lives on, sorta like dodges don't start in the rain
OMG this is funny.

[cubes]

So along with poor oiling is it the lifter bouncing off and pounding the lifter wheels against lobes due to poor spring control being one of the factors another or major cause of solid lifter bearing and axle failure ?

[Jay Allen]

The good lifters today will oil properly.

Get good springs, and you'll be fine.

Also a billet cam core as well. I cannot believe how many people use SADI cores for street rollers. That is simply asking for trouble.

Good Luck.

[cubes]

thanks, done(crower with Hi-p oiling) and done(comp pacaloy sprigs and billet core courtesy of yours truly). Just curious as to what else determines the life of a solid roller lifter given that it is well looked after by matching reciprocating parts.