Steve93Talon
20+ Year Contributor
- 1,629
- 175
- Jan 20, 2005
-
Philly Burbs,
Pennsylvania
Well am I the only one? I've run a t31 60-1 with no exhaust with the stock BEP internal gate. No creep. I've run the h1c with no exhaust and a 29mm hole with a 38mm external gate. No creep. . . What am I doing?
This is funny because I remember back in the day DSMers b!tching about not being able to run more than 20-22psi with their rs49s and bep 50-trims and other bep bolton housing turbos. The flapper would blow open and boost would not go over 22psi. I don't know about you but there's no turbo you want to put in the bep housing that you want to be running under 20psi. So if it were creaping to 20 psi then blowing open and not holding more than 22, then these bits of information were never relayed by all those reviews. And again, I've had 2 of these housings with 2 different turbine wheels, both with either stock BEP hole or 29mm hole and have never seen creep. But I have blown open the flapper.
I think the difference here is internal vs external gates. I ran a Tial on the o2, so opening up the port leading to it allows the gate to function effectively. On an internal configuration, you're dealing with a lower spring pressure so porting the passage only puts more exhaust pressure on the flapper to blow it open sooner.
I agree that you shouldn't really be worrying about running less than 20-22psi on a turbo using these housings, but I was trying to dial in a new setup from scratch and it's no fun doing a baseline pull at 14.5psi gate pressure and watching your gauge shoot to 25 in a blink.
This is basically a "your mileage may vary" kinda thing. Wheel size/efficiency, engine VE, gate size/spring pressure, displacement... will all affect how the wastegate operates. I guess the rule of thumb should be external on o2 - port the hole, more cant hurt. Internal gate, start with the standard hole, watch for creep, go from there.
Id rather find around a 17cm or so t4 housing that will work with it and get the JHRacing manifold like the hx52 guys are gunna use, but i havent found any t4 housings in the teens yet. I havent really seen any divided t3 manifold that id want to spend the money on. A divided t4 manifold has a wider variety of turbos that i could use it with, and would probably have an easier time selling if i changed my mind.
. I'll retract and say that he has all the upgrades to his old setup to shave several tenths off his last best time.
, i had an old one hanging around and it was the perfect size!