Maybe Steve Oldani or one of the other trans experts can share thier thoughts on which way is best.
Dual purpose TH350; is it worth the extra money to have the rollers instead of the washers?
Any performance gain to be had??

free ET, no matter how big or small, is worth it, unless you are paying through the nose.

It wouldn't be free ET...

It is somewhat expensive and time consuming to try and roller everything.

There are some locations that can be easily done, and if youdon't mind robbing cores of parts it can be done.

On a TH350, later model units had a roller pump to direct drum thrust, as well as between the forwar drum and input ring gear.

The roller pump body is a good almost free upgrade. They are all rollered between the direct and forward drum, so no biggie, but the late roller style input ring gear makes me nervous for a drag application because it takes ALOT of material off the front of the input ring gear.
I've had the thicker one piece input ring gears break in N2O applications, the three locating slots cause them to fracture.

On a TH400 the rear planetary to case thrust and selective can easily and cheapy be replaced with a torrington, the forward to direct drum can also be replaced.
All the sun shaft is already rollered, and the forward drum to pump is not worth messing with, as there is very little thrust loading, I just try to set up the endplay about .015 and it is fine.

So for the most part, not really worth the trouble. I do ALWAYS do the rear thrust in a TH400 but it is super easy and cheap and requires no robbing of cores or extensive rework.

Forgot to mention...

The difference between a stock thrust washered trans and a fully rollered setup is worth maybe .005 ET... really very little effect on ET. ATF is good stuff..

But IMO more gains can be had by using specific clearances and clutch pack setups.

For example,
If you are using a TH350,
use FEWER low/reverse plates and keep a loose clutch pack tolerance as well as using the late model 4L60-E steel plates with "turbulator holes".

Reasoning is to reduce friction cause by driving through the clutch once the trans shifts out of 1st.

Same deal on the intermediate and direct cluthes as far as clearances go but retain all the clutches..

Run the directs loose because you have to drive through them in 1st and 2nd.

I would also use slightly looser band clearances as long as they have no critical upshift timing like a 700-R4, 200-4R, etc.. and use heavier band return springs.

Also letting a trans shift automatically SHOULD be worth some miniscule ET.
On a TH350 it uses the low/reverse plates in manual low but does not in auto low, so they do not have to release. TH400 is the same deal but it is a band setup instead of clutches.

Hughes I believe also has some steels with rubber on the edges to act as a spring and cause the clutch to release quicker.. A modern way of using an old trick.. and much easier.

Using loose clutch clearances might gain .01-.02 ET, MAYBE depending on how your builder sets up clearances anyway...

For a Bonneville car I use 1 low reverse friction in a TH350... redface.gif Just enough to have reverse under light throttle smile.gif

You can also use TH250 sun shell to lighten up the internals on a TH350.

Thanks for the replies.
They want $175 for the roller setup.
At this point,apparently, the money can be better spent elsewhere.