I have the IP turned up on my 6.2 and really enjoy the extra drivability it provides. When I'm puting my 6.5 together, I figured that it would be a good time to crank up the fuel delivery a bit, but thought that I should ask for advice first. I turned the 6.2's pump up about 3/8 of a turn and it's still completely smoke free. Would a similar amount corellate to a 6.5 turbo IP too?

Oh, yeah, I have a boost gauge and EGT gauge to install at the same time. My turbo is healthy with no shaft play at all. I am probably going to make a mechanical wastegate controller to get a little bit more boost.

So, I guess after all of my humming and hawwing, what I really need to know is what are the hard numbers for how much boost and how much extra fuel (measured in x/8 of a crank on the IP's fuel delivery screw) would give me a mild increase in power (and fun)?

Are there different mechanical IPs for the turbo version 6.5 as opposed to the non-turbo version 6.5? I would think that if the answer is yes, then you would want a turbo IP version as it is already set for increased fuel. That way the turning up of the IP wouldn't be so drastic.

If not, then I guess this post was just a waste of everyones time :rolleyes: Sorry!

I turned mine up about 1/4 turn and got some smoke but higher egt's. I also had straight pipe exhaust. I didn't care for the outcome - not much more power. I definetely would not do it if you haul anything heavy.

I do tow from time to time, so maybe I'll just leave well enough alone. The power from the 6.5 is so much better than my 6.2, so that is an improvement as is!

I fabbed a adjustable wg controller for my '93, had the GM-3 turbo on it then and bumped it to about 10psi. Then i turned up the fuel 1/8 turn, made a great improvement. I'm installing a GM-8 this weekend, should be interesting to see what that looks/feels like. I've got gauges, and i think the increased boost & more fuel go hand-in-hand. To tune it you'll have to watch the boost & pyro to get it in good shape. Good luck.
Don

Without a better than factory exhaust, wastegate controller I wouldn't touch the fuel just yet.

Daustin I'll be interested in your results of the turbo swap.

I'm hoping that with the long weekend i can get her running. With the GM-3 and std wastegate controller it ran ok, but didn't tow up to my expectations. I fabbed an adjustable controller, but didn't tow with it and decided it was time for injectors..etc. It ran better with the boost cranked up some, i had about 4-5 psi with the factory setup, and with the adjustable one i pumped it to 9 psi (with some reccomendations) and 1/8 on the 4911. I'm hyped on seeing what it's like with the -8 and the new downpipe. I've fabbed a mechanical actuator for the -8 as well, another $15 and an hour. hehehe Have to see if the spring i chose is ok for the application. (secret but avail at any auto parts store, i'll post if the results are ok) I've been working out of town, 61-65 hours/week and only back home for 24-36 hours on the weekends. I lack straightening the A/C radiator fins, re-installing the radiator and new downpipe, new balancer/pully and SSD dmax fan/HD clutch and fire her up.
I'll post with my "butt-dyno" results. :D
Don