J Chen

Todd, BTW, I did tried both set up & found
that in my case regulator before reliaboost
work much better. Lastly, are you using
stock or aftermarket wastegate ? That would
make a difference due to the spring tension
in the wastegate. In anycase, be gentle with
the settings.

toddk911

Ok, I will try that set up.

So your running the Reliaboost as the relief valve?

As that may be why you saw a difference instead of using the relief valve mentioned in the article.

I have a GURU rebuilt, so the spring is improved from stock.

J Chen

Yes Todd. Once again be very gentle
while setting the boost level. I over did
it & momentarily saw 25 psi but thank
goodness I was in third gear on an
uphill climb.

dhallilama

Whoo-hoo... 25psi musta felt good for that brief moment!
I so worry about high boost... dont exactly want to come back down from it. Must be kinda like heroine.

had a 240sx with a turbo sr20det... got to the point where i was daily driving it with 28+psi. Blowing stuff like crazy, but (at the time) a cheap engine to replace.

toddk911

So when are you seeing full boost JChen?

J Chen

I was more worried about a blown
engine or causing a blown gasket
dhallilama.

J Chen

I'm seeing 1 bar at 3000 rpm but that's
with a slightly leaking exhaust. Going
over to an Apexi AVCR soon cause I'm
getting one for free. BTW, I'm running
a GT25TO4S turbo.

toddk911

Well, when I was taking it apart to try reversing regulator and relief, as Jchen suggested, I tried adjusting the regulator and blowing and found that the body itself was not tight and was leaking. So I tightened it and no more leak. I will try it again on the car soon. Hopefully that was the problem.

Jchen, you are useing this same setup except:

The reliaboost as the relief

And you run the regulator first, then the relief

Correct?

toddk911

Ok, 1 bar at 3K is nice!!. When were you seeing full boost beofre this controller set up?

J Chen

Yes Todd correct & am still using it.
Before got to see 1 bar at 3300rpm.
Try both set up & see if it makes a diff
for you.

DanG

Hey guys. I don't own an 951 (yet) but have been following this post. I started messing around with turbo dodges a few years ago to learn how to blow up engines the cheap way. I'm finally through the "boost till it blows" phase and am approaching the level of maturity required to own/tune a car thats not quite so cheap to replace engines in (try $300 for a good used shortblock on the turbo dodges).

Anyway, I thought I'd share a couple turbo dodge boost control links...

http://www.thedodgegarage.com/turbo_boost.html

http://www.xmission.com/~dempsey/perform/

they cover many of the same ideas you guys are talking about here. They also go into some designs of staged boost control, which is basically just multiple boost controllers at different settings, selected via soleniods. The other good thing is everything they design is CHEAP.

Just thought some of it might be interesting reading for you guys. I don't think they have any new secrets, just a little more discussion on the topic.

Also, J Chen... did you ever finish/evaluate that cheap DIY anti-lag device I posted about back in July '04?

toddk911

Chen: Are you still running with the Audi Controller? And did you say you used the reliaboost in place of the other regulator?

toddk911

Oh sorry, the relief.

And in what order are you running them? relief first then regulator?

I tried running jsut the Reliaboost with the check valve and did not notice any difference.

Right now I have the relief and then the Reliaboost as the regulator and not noticing much difference.

toddk911

Dan, do you have under hood pics of the DIY device?

J Chen

Hi Dan,
How's the going ? Yes I did try it on my friends Imprezza.
It does work but it was not like night & day diff. The AFR
did require some readjustments too.