Looking at going XS to4S with custom wheel to replace the twins (coming over to the dark side). Checkpoint just put one in and it had lots of end play after only a few hundred miles. Sent it back to XS and they said it had oil supply failure. XS uses a restrictor on the oil feed line - but Checkpoint's only seen that on ball bearing, not plain bearing. Anyone out there have oil feed restrictors on their plain bearing setups? Anyone else had oil supply issues like this?

Just looking to not blow another bundle and not get any real enjoyment out of it.

Beast

 

I'm not very experienced in this... So it's not fact, just what I hear... But to my understanding, a TO4S/R can have an unrestricted line (-4AN~) to the turbo AS LONG as the return line can flow the oil out. It makes sense, but I have no experience. I've heard a few times that the XS kits fail due to the restrictor. Maybe someone here can clear things up.

 

I have had my T04s setup for over a year now with no problems. I do not have a restrictor in the oil line. Same is true for a friend of mine.

Chris

 

Thanks VERY MUCH!! Now I'm not scared to leave mine out.

 

I've got one...

 

No kidding, i saw that turbo and its bearings were HOSED. Obviously oil starvation, but why in the world would that happen, i would think this would have been worked out already (by XS).

I agree beast, that T04S is pretty tempting, but im gonna wait and see how the GT70R's work out....

 

I have -6 oil feed and -6 oil return and my car's 62-1 is throwing oil out the downpipe. I have to put a restrictor in my feed line.

 

Your return should be like -12AN. That could be why you are puking oil... If you're feeding it with a -6 it needs LOTS of room to dump out!

 

Based on what I've heard, there are two options:

1 - Use a restrictor
2 - Use a larger return line vs. feed line (same net effect as 1 above).

I've seen a couple of different sized lines being used, which would affect oil pressure (so would the restrictor). Any idea of optimal feed pressure?

Beast

PS to Fatty - yeah, there's always going to be some new turbo coming out, but the t04s has good history and good power/spoolup combo for street/strip. Works for me - once we approach 400 rwhp the useability factor starts going down.

 

The turbo that the beginning of this thread talks about is mine. XS fixed it and it's going back in without the restrictor. If it smokes then it'll get jetted.

 

When you go too big on the oil feed you end up starving the ENGINE !!!!.

 

Yes, once the issues with your motor/turbo are worked out, mine is next on the list. It's just tough waiting :-) I've been without my car since April....

Beast

 

April, thats nothing, mine has been there since around December. I'm very sure that it'll all work out in the end. I've got a lot of faith in Chris and his abilities.

 

Billy

I wouldnt worry too much about your car. I know its been a long time (hey its taken me years and im still working on my car) but your car is going to be wicked fast. I was there the first day the car was started, and also when it came back from its first dyno run. The car just BEGS to boost and the starting and idleing is great. Just hang in there....

I agree with the fact that the T04S has some history and is a good turbo. Im still interested in the GT70R because its ever so slightly smaller than the T78, but with better blade designs and of course full ballistic bearings. Will have to wait and see i guess. Im not going to do anything more to the motor i have now, ill wait and build a 2nd motor for that stuff (13B-RE).