Competition Need 12 valve tuning help...

[Morse]

Well, the last time the truck ran was at the TS race a couple months back. . I believe water pressure was my problem causing a blown headgasket. That was taken care of with an electric pump. I also went ahead and installed a billet cam. The truck had good power in Bowling Green, and rolled through the eighth mile traps at 94 mph with only a few seconds of wide open throttle. I put it on the dyno, and this thing is making no power or torque. I could only make a third gear pull with no lockup, but the numbers were horrible. It was around 500 hp, and 700 torque. Everything seemed to be screwed up. . My boost gauges were hardly moving. I don't see how I could have trouble with boost gauges, but I did, even though everything looked fine. I did go with . 120 lines instead of stock, but I didn't think that should hurt much. timing was set at 23 degrees. I spun it to 4500 rpm in third. . Wheel speed was 121 MPH. I just feel something must be bad wrong to show such low numbers. . Especially the torque. . Does anyone have any ideas? I'd love to go to Rockingham, but there's no way I'm taking it the way it is. Anyone have an idea why the numbers are so low? I don't even know how to set my wastegates, so that lets you know how lost I am. I may have to make a call, and see if Garmon can get me in. .



I came to KY to get the race truck and go to Rockingham, and already broke the output shaft on my daily driver dually as well. Not a good time so far.

 

[DPS]

Couple thoughts, cam timing could be an issue? I personally think your timing is too low to turn big rpm with good hp, but I deal with pullers normally not racers and I know there are big differences in how we develop revs. As far as the twins setting the gates will need the advice of who ever built the setup to determine the optimal pressure ratios between the two



Josh

 

[zstroken]

I think that 23 also seems a little low for 4500. Dynos don't load a truck like sled pulling. I could hit 1750 on the pulling track and could only hit 1300 on the dyno.

 

[Morse]

I took a look at the sheet, and it made peak power around 3700-3800 rpm. At 4500 rpm, it hit 1600 degrees and was climbing fast. For a third gear pull with no lockup, I heard 121 mph was pretty good, though there are just issues that are majorly holding it up. The turbos were setup by Shane at Industrial Injection. A combination of timing and wastegate tuning is hopefully the answer. Too bad I just don't know how to do it. . haha. . I have really been looking forward to going to Rockingham, though there's no use me going with it like this. If tuning the twins is going to be fairly difficult, there will be an II hybrid big brother poole twin setup made for a 2nd gen on the market very soon. I have the nitrous now, and I'll just run the 66.

 

[Timbeaux38]

It will take a single and spray to be competitive. I know of 4(dodge) trucks minnimum that will be running that combo in Rockingham

 

[JoshPeters]

Give the boys at II a call. Tell them what you are dealing with. They will probably have an answer right away.



They can also tell you how to tune on the twins you bought from them.



JP