toni

does any one know if a P1 has a roller bearing turbo

richiewong

AFAIK it's an IHI VF28 roller bearing turbo as fitted to STi 5's.
But could be wrong

RB5_245

I thought It was a VF30 which is not roller bearing.

I have been told I'm wrong about this though, so I don't know

.....erm.... so that was pointless

Dave

R.B

Its not a Roller Bearing turbo

CustomScoobyIOM

Not

R19KET

I'm sorry, the P1 uses a VF28 as Richiewong has stated. This IS a "ball bearing" turbo.

Personally, I've never seen "roller bearings" used in a turbo, although they may in some. Turbo's generally use either a"sleeve bearing", which is more like a bush, or ball bearings.

Mark.

toni

Mark.[/QUOTE] Personally, I've never seen "roller bearings" used in a turbo, although they may in some. Turbo's generally use either a"sleeve bearing", which is more like a bush, or ball bearings.



well i had a skyline with hks roller bearing turbos ,and the reason i ask it that when i switch the engine off on the gtr you could still hear the turbos spinning and the P1 seems to do the same,just thought it might have a bigger turbo as it dont come on real boost until 3500 rpm and it has a open neck down pipe with no cats

Scott.T

iTrader: (2)

It's a VF28 and is classed as a Roller Bearing (as per STi 5 & 6)
see http://www.isrperformance.com/turbo-data-28-3-02.pdf

It's basicaly a VF24 with an actuator from a VF22

R19KET

Ok, it's partly down to interpretation.

Some people seem to call a bearing that uses "*****", a "roller bearing". I've always been lead to believe that a "roller bearing" was made up from rotating cylinders (rollers)

Either way, the P1 had a VF28 turbo fitted as standard, the bearing is of the "ball" variety,

Mark.

TonyBurns

iTrader: (3)

Oh lots to this roller bearing/sleeve bearing thing
But to the best of my knowledge this is the difference
(in easy to understand terms )

Sleeve bearing:-
Just imagine a cup, now shove a tennis ball in there, it fills the space fully, 100% contact area (friction = wear), the down side you get is that its very hard to get moving, you will feel the drag, this means that you get slower spool up due to friction, but its a cheaper way of building turbos.

Roller/ball bearing:-
Do the same as above, just drop one of those small 1cm ball bearings into the same cup that fits that standard sized tennis ball, roll it around, minimal contact, virtually no friction, this means virtually no wear on the bearing, easier to get moving, quicker spool, more expensive to manufacture i believe due to a bigger housing? (please quote me if im wrong )

Tony

RB5_245

Sleeve bearings run on an oil film if I am correct, which means less moving parts and cheeper to overhaul, although quicker wearing.

Roller bearings are rotating cylinders which give the least friction but are not good for angular contact, ie horizontal thrust.

Ball races arn't great in my opinion as they expensive to replace and not as efficient as roller bearings although there are a huge range of clearences and types to play with.

If you were to put the wrong oil into your car, or didn't change it for far too long, the sleeve bearing one would be the most likely to hold up.

I don't think a ball race turbo would be the way to go at all, roller or sleeve for me thanks.

Completely off topic and of no point at all

(Where on earth did this rant come from )

Dave