Turbomaster, stock programming

[big61fourby]

Been reading some of the archives on the turbomaster (P0236 the other night...), but wonder how many of you guys 1996 and up are running one. Noticed on Heath's site that its not recommended with stock programming, whereas the pre-1996 unit doesn't have that clause. So what's the deal with OBDII trucks, can you not use the resistor trick to fool the computer?

[GMC Hauler]

I ran it with no problems. I don't think there any problems with running it, as long as you keep boost below the maximum the PCM wants to see. If you fooled the PCM into thinking that boost was lower with the resistor as you stated, it wouldn't be the wiser. Although.... after a point extra boost is useless unless you apply extra fuel to it.

You can use the resistor trick

[big61fourby]

That's exactly what I wanted to know. Thanks!

BTW, are you still running it, or no? I didn't see the pics on your page, but maybe I'm imagining things...

[DaveNY]

Have been running TM with stock set up and all is well. When first installed I had problem with 0236 but installed boost gauge and found that GMC Hauler's suggestion was correct and the Heath setting for stock unit was too low. I ran the nut in untill I saw 8-9lbs max and the truck was very happy.
Dave
PS: The -1.94 TDC Offset really helps out

[GMC Hauler]

That's exactly what I wanted to know. Thanks!

BTW, are you still running it, or no? I didn't see the pics on your page, but maybe I'm imagining things...
I never used a resistor to fool the boost sensor. I got boost to 8 lbs with the stock PCM and a turbomaster. Later, I ended upgrading with the Heath PCM, and then changed springs on the turbomaster and adjusted for a higher boost level.

You should not need more than 8 or so lbs with the stock PCM.

If i remember correctly, the engine without the EGR (i.e. a F code) is tolerant of more boost. Which version do you have, with or without the EGR?

[big61fourby]

I have the non-egr version. I don't remember the RPO off hand, but IIRC it's the 8600 GVW (the heavier 3/4 ton). I don't know the actual build date, but it must be real late in the 1996 model year, because I have dual t-stats, upgraded CAD, and the newer fan/clutch.

I'm really not looking for huge boost numbers, mainly a simpler alternative to the current vac system. 10 psi peak is all I'm looking at. I guess the nice thing is I can tweak it until I'm not setting codes all the time. :) Thanks!

[GMC Hauler]

If you're looking at getting rid of the vacuum system, you can do it easily. You can remove the vacuum pump easily, and use a shorter belt, about 20mm shorter. Remove the vacuum lines and dashpot on the turbo. The solenoid can be left in place, or a 20 watt, 50 ohm resistor can be used to replace it.

You can make your own spring wastegate, or buy one from Kennedy or Heath.
You are right on, tweak until you set a code or the exhaust is clear without smoke.

[JohnC]

The solenoid can be left in place, or a 20 watt, 50 ohm resistor can be used to replace it.

Just FYI, a 5 watt resistor ought to by plenty big enough.