Computer chip questions

[Jim P]

I just installed a used chip that I bought from Phil Holmen.BTW thanks Phil. It did not have any instructions but I just removed both ecm fuses and then removed the ecm and installed the chip. Is there anything else that I need to do?

I took the truck for a drive and it definitely has more power. The only thing is that now it smokes a little even after the boost comes up. Is this normal, with a chip? I am running 15 psi boost after the intercooler. I also have high flow injectors. It used to smoke pretty heavy if I would mash it to the floor when I was going slow in high gear but the smoke would clear up after the boost came up.

With my vertical exhaust, I think my new 30' fifth wheel camper is going to look like the side of a semi van being pulled by an old Mack.

[charliepeterson]

From your signiture youv'e done alittle work to the truck. Now you have more fuel going in with the "chip" and boost is good, what is the timing of the engine now. Try bumping it up to -1.94 TDC to get a little better fuel management.

[gmctd]

You could also stand more Boost with that 18:1 engine, to 18-20psi full throttle.
If you're running the GM-X series turbo, 15 psi is a little over max efficient boost, so would require replacement turbo, maybe a Mitsu TE06H, or a set-up Garret T-4.

Black smoke is too much fuel, not enough air - you need more Boost, and a charge air cooler would certainly help.
And timing, if it's still at factory 2500 setting.

If your truck were the 2500 EGR no HD, you would already be at -1.5deg, so have that checked, as Charlie suggested.

[whatnot]

Originally posted by gmctd:
If your truck were the 2500 EGR no HD, you would already be at -1.5deg, so have that checked, as Charlie suggested. Mine was at -0.5 when I got it. It is a L56 K2500 (non-HD)

[gmctd]

Good info (raises yet another question), and further reason to have that timing checked.
Boost, timing, and cool air should be the fix.

[Jim P]

My timing is set to -.5. I wish that there was some way for me to set this myself. I have access to a scanner that will read the offset but I have yet to figure out a way to change it. The truck is a hd. I will also try turning the boost up a little. I already have the liquid intercooler installed.

[Turbine Doc]

Jim P,
I changed mine by APP to floor key on key off reading Snap On scanner for position and then loosen/rotate IP to correct setting, mine was -.5 now -1.5 , but mine is OBDII PCM, I don't know if it works the same for OBDI if you want I can email what I used.

[Jim P]

The way I understand, the method of using the accellerator pedal only works for the OBDII. If anyone knows of a way to do it on the OBD I, I would love to hear about it.

[gmctd]

My engine started out in life as K1500 EGR -1.5 TDC Offset.
I used a K3500\NV4500 PCM to prevent problems with using a T400 auto trans.
The K3500 TDC was -0.5, and the thing ran somewhat hard for a while, but settled out.
I later had the timing checked, and the OBD-I PCM had learned the new timing and -1.5 TDC Offset over a period of starts, maybe 50, as the manual suggested it could.

You might give it a try, moving the inj pump incrementally. You will be advancing the pump from 3.5deg to 8.5deg, but not all at once, without a Tech-X scanner.

[gmctd]

I need to restate something here, considering all the info I overlooked in your post - 15psi is absolute useable limit with the GM-X series turbo.

No need to try any higher boost level with it, as exhaust back-pressure goes outta sight over 15psi.

Up goes EGT, up goes IAT, up goes ECT, down goes power.

You've got hi-flow injectors and now higher fuel rate, so you will need more boost, but not with that turbo.

And more timing - to 8.5 ~ 10.5deg.

John Kennedy played with these 18:1's the most, and very successfully, so a call to him would be more productive.