TTi Stage X - Upgrading Turbos Questions
 

Just a few questions for the guys who have upgraded from the base Turbonetics turbos to Precision 6265 or 6266s..

1) Is there any reason to buy the 6265s now that the 6266s are available?

2) Did you go with journal or BB?

3) How is the spool relative to your older base turbos?

4) What else in the kit has to be upgraded to support larger turbos? Did you upgrade the generic 38mm gates? BOVs are a given.

Pound for pound what sort of power increase did you see?

Thanks

I don't think the 6266's are available on our cars. Did you call tt to confirm?

I haven't, no, but I thought the 66 had the same form factor as the 65.

I'm planning to answer some of these myself. I'm looking to upgrade with 6265 in the spring. TTi recommends BB without a doubt.

Probably because of the back pressure issues. I would be curious if there is anything that can be cleaned up / ported with the stock manifolds to reduce that pressure or if you're better off with a one-off T4 setup.

Pretty sure all the back pressure issues are due to the t3 turbine housing at really high power levels. I doubt port matching the manifolds will make a difference. I suppose running the largest turbine wheel (I'm sure the 6265's already have this) and clipping it might help, but I don't see many clipped turbine wheels on our turbo apps. Clipping is more common on turbo platforms that don't have a lot of upgrade support. It's not really the "proper" way to do it, but it does work.