roller bearing turbos.....

roller bearing turbos.....

Author
Discussion

andygtt

Original Poster:

8,345 posts

271 months

Tuesday 21st September 2004
quotequote all
Anyone here have experience with these......

I wasn't planning on fitting these to my V12 as I thought the engine would spool some large T4's up quite easily anyhow and the fact that its a 5L V12 will mean more than enough low down torque for my 1100kg mid engined car.

However I have been told the throttle response alone would make them worth it.... then there is the fact that I can run larger turbo's with less lag and less stress.

any views?

stevieturbo

17,535 posts

254 months

Tuesday 21st September 2004
quotequote all
Generally speaking, the claims of increased performance with roller bearings is actually small.

They may claim perhaps say 20% better spool up time. But if that only takes 1 sec, then the gain is only to shorten that to 0.8sec.

One area they are better, is that they resist high thrust loadings better, and tend to allow higher rpm's ( turbine rpm's not engine ) before they destroy themselves, so in some ways are more robust.
But generally speaking, most full roller bearing cartridges cannot be rebuilt if damaged.
that means new turbos.
Many gains fom people swapping from an old oil bearing turbo to RR arent soley from the RR, but from the different compressor and turbone specs they happend to upgrade to also.

Basically, if you can afford it, then by all means do, but a well sized oil bearing turbo, will be virtually as good, a fraction of the cost, and if damaged, easily repaired.

cymtriks

4,561 posts

252 months

Tuesday 21st September 2004
quotequote all
I can't see why a ball bearing turbine and compressor shaft should be any better than a roller bearing one. I suspect that there are other factors in the turbocharger assembly that make the real differences.

By roller bearings do you mean taper rollers? This type would be less capable of high speed than other types and would probably have greater drag. A plain roller mounted shaft would still require a ball bearing somewhere on the shaft to take the thrust load as plain rollers have very little axial capacity, especially at speed.

Large jet engines have one ball bearing and one or more roller bearings per shaft. Smaller engines are similar though the smallest ones sometimes have two ball bearings on a shaft.

stevieturbo

17,535 posts

254 months

Wednesday 22nd September 2004
quotequote all
To be honest, not actually sure of the makeup of the bearings, but they are branded Roller Bearing turbos, and they do work well..

But they are also about twice the price of the equivalent normal type turbo, which is also tried and tested.

A few turbo links....

www.forcedinductions.com/
This guy has always been very helpful with enquiries.
Or try his Forum, not usually too busy though.
http://forcedinductions.com/ipw-web/bulletin/bb/
At least if you ask on a public forum, others may benefit from the answer too....

http://store.yahoo.com/cheapturbo/gartur.html
Despite the name, I think Jose at Forced Inductions can match or beat their prices.