Now I'm getting into my 200-4r rebuild the questions are coming thick and fast
For some background, I bought a very rough looking core unit after a long search, to put in my 1980 vette. See the thread linked here:
http://www.turbobuick.com/forums/transmission-talk/310891-cu-code-200-4r.html
I want to build it for reasonable power, although my vette is probably under 300 hp/tq, I want it durable, and capable of coping with any further engine upgrades I might carry out.
So I'm building a shopping list of jobs and parts for this unit. One thing I've noticed is that many folk seem to advocate rollerising in some of the thrust surfaces where plain thrust washers are normally used. I'm debating whether I will do this or not. If I do, I can machine the bearing pockets myself, but I'm wondering whether this is really necessary for a non-competition transmission.
I happen to know a bit about bearings and lubrication so I hope I'm making educated assumptions here, but am I right in thinking your prime goal in replacing plain thrust washers with roller thrust units is the reduction in losses?
In theory (a dangerous way to start a sentence I know!) the load support of a properly lubed plain bearing should be a lot greater than that of a similarly sized roller unit. But in terms of drag losses the roller unit is much lower. That to me says that for durability one would stay with plain, but for all out racing where every little fraction of HP is crucial, you can justify going to rollers.
I'm not trolling for an argument because "I think I know the answer" here; as I said I know what the theory says but the practice can always be much different. Just interested to hear what the experienced builders have to say.
Cheers
Theo
For some background, I bought a very rough looking core unit after a long search, to put in my 1980 vette. See the thread linked here:
http://www.turbobuick.com/forums/transmission-talk/310891-cu-code-200-4r.html
I want to build it for reasonable power, although my vette is probably under 300 hp/tq, I want it durable, and capable of coping with any further engine upgrades I might carry out.
So I'm building a shopping list of jobs and parts for this unit. One thing I've noticed is that many folk seem to advocate rollerising in some of the thrust surfaces where plain thrust washers are normally used. I'm debating whether I will do this or not. If I do, I can machine the bearing pockets myself, but I'm wondering whether this is really necessary for a non-competition transmission.
I happen to know a bit about bearings and lubrication so I hope I'm making educated assumptions here, but am I right in thinking your prime goal in replacing plain thrust washers with roller thrust units is the reduction in losses?
In theory (a dangerous way to start a sentence I know!) the load support of a properly lubed plain bearing should be a lot greater than that of a similarly sized roller unit. But in terms of drag losses the roller unit is much lower. That to me says that for durability one would stay with plain, but for all out racing where every little fraction of HP is crucial, you can justify going to rollers.
I'm not trolling for an argument because "I think I know the answer" here; as I said I know what the theory says but the practice can always be much different. Just interested to hear what the experienced builders have to say.
Cheers
Theo