Wit's End Turbo Owners - Thread #2.....
- Thread starter OutlawMike
- Start date
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I'm currently running an innovate SCG-1 for boost control/wideband (subject to change as I move to a standalone) but currently running a 4psi spring and a 3 port solenoid.
Light boost/part pedal I see around 3-5psi
I have boost control set to 7psi (easily achievable above 2400rpm with heavy pedal)
Truck is 160k, but its a fresh (ish) build ~5000mi on a brand new OEM shortblock and I went though the head/had it cleaned up. MLS headgasket, arp studs, kelford valve springs. Injectors were reman units with the new engine, new fuel pump, fuel filter, pressure regulator, etc all at the same time.
As @scottryana mentioned I am probably also struggling due to current temps here (single digits) making the air extra dense.
Light boost/part pedal I see around 3-5psi
I have boost control set to 7psi (easily achievable above 2400rpm with heavy pedal)
Truck is 160k, but its a fresh (ish) build ~5000mi on a brand new OEM shortblock and I went though the head/had it cleaned up. MLS headgasket, arp studs, kelford valve springs. Injectors were reman units with the new engine, new fuel pump, fuel filter, pressure regulator, etc all at the same time.
As @scottryana mentioned I am probably also struggling due to current temps here (single digits) making the air extra dense.
- Thread starter
- #224
A little late on my reply:
Running a boost T with the Wit's End wastegate running 8.5 PSI springs. I have the boost T adjusted for a max 10 PSI boost.
The boost T also has a feature to reduce wastegate creep, so, it comes on boost a little faster.
When I really get on it I overshoot 10 PSI and the boost alarm goes off. I see 10.3 PSI before the wastegate catches up and gets it back down to 10.
I am running Landtank Scaled Injector Kit with a Supra fuel pump. I do not see any lean conditions.
I swapped in a ZF8HP75 transmission two years ago and it really woke up the turbo swap. I stay in the boost during shifts now and pulls like mad.
182,000 miles.
Running a boost T with the Wit's End wastegate running 8.5 PSI springs. I have the boost T adjusted for a max 10 PSI boost.
The boost T also has a feature to reduce wastegate creep, so, it comes on boost a little faster.
When I really get on it I overshoot 10 PSI and the boost alarm goes off. I see 10.3 PSI before the wastegate catches up and gets it back down to 10.
I am running Landtank Scaled Injector Kit with a Supra fuel pump. I do not see any lean conditions.
I swapped in a ZF8HP75 transmission two years ago and it really woke up the turbo swap. I stay in the boost during shifts now and pulls like mad.
182,000 miles.
- Thread starter
- #225
Found a boost leak location - EGR Vacuum Modulator Valve
A lot of guys are probably not running their EGR valve, but, if you are, the Vacuum Modulator Valve is a potential boost leak location.
A few weeks back I noticed getting on the freeway that I was not hitting 10 PSI boost when I railed it. Got out the Amazon smoke machine and found smoke pouring out of the EGR Vacuum Modulator Valve. Looks like I blew that thing open with the higher boost.
I picked up three check valves and installed them on the vacuum lines. No more smoke comes out, and I am hitting max boost just like before.
If you find you are not hitting the boost you think you should be, smoke the engine and pay attention to the Vacuum Modulator Valve.
Mike
A lot of guys are probably not running their EGR valve, but, if you are, the Vacuum Modulator Valve is a potential boost leak location.
A few weeks back I noticed getting on the freeway that I was not hitting 10 PSI boost when I railed it. Got out the Amazon smoke machine and found smoke pouring out of the EGR Vacuum Modulator Valve. Looks like I blew that thing open with the higher boost.
I picked up three check valves and installed them on the vacuum lines. No more smoke comes out, and I am hitting max boost just like before.
If you find you are not hitting the boost you think you should be, smoke the engine and pay attention to the Vacuum Modulator Valve.
Mike
G
I’ll run another smoke test to see if this one is torched. Good idea on the check valves
Interesting. I had one fail one me that was old and figured it was just worn out.
I’ll run another smoke test to see if this one is torched. Good idea on the check valves
If if your vacuum lines are holding and you still lack the boost, look at the exhaust system…mine was a new OEM system maybe 4 years old and restricted boost like you wouldn’t believe..custom 3” from the down pipe back got me all the boost I had paid for
Just following up on this in case its helpful for anybody in the future.
I was running a set of "bosch style" reman injectors from cruiserparts, they were an older version that what they seem to currently be selling. Based on googling part numbers I believe they were actually slightly lower flow than the OE denso units.
I freshened up my set of stock injectors and put them in and the truck was happy running around 5-6psi. Fuel trims seemed better as well.
I ended up moving to a standalone/bigger injectors which makes it a non-issue, but just a warning about non OE injectors.