The M.D. Dyno has the ability to let you run the 1/4 mile. I have no idea how close this is to the drag strip, but my Neon buddy ran his car here and posted a best time of 15.6 at 89 mph. His best strip time is 15.07 at 91 mph. What does this tell me about the time I posted on the dyno!!? This was not a hard launch, so the 60 ft time shows that. I am quite pleased with the imporvement, and there is more to come. I didn't post it yet, but the power curve shows the car still quits making hp after 4900 rpm. If you look inside the throttle valve, you will see how small the throat is on the stock PT. The way the stock intake splits up top into two sections is fine for low end torque, but murder on hp up stairs. Again, this is just an air pump, so any restriction will effect its' efficiency. Plus I don't really have control of the fuel curve yet, so it is rich up top. One interesting note, is the Whipplecharger totaly replaces the stock PT intake, so there is no restriction to deal with in the intake track. As my boost pressure is going up, I am beginning to see a fall back in boost, (2-3 lbs) while accelerating through the lower gears. I am not sure if this is a flow issue or the way I have been "tricking" the boost controller to jack the boost above the pre-set 6 pound level from Hahn. It didn't begin to show up until I exceeded 10 psi. I tried 12 lbs boost last night and the motor seems happy. The supprise I did get was the clutch broke loose in 4th gear. I was at 50 mph comming onto the interstate, pushed the pedal down, the boost spiked up to 12 psi and at 65 mph the engine reved up slightly. I backed off, tried it again with the same results. This may be the spot where I have to deside to stay 10 psi or below, until I change engines and/or clutches. The clutch is still grabbing fine, launches and hard 1-2 shift bark the tires at will, but at 12 psi boost the engine is possibly making over 240 ft lbs of torque, to a clutch that is rated for 200, so I'm told. I will be checking that out. None the less, I have found the first weak link in the "drive train".... NOT a failure, but it will be if I don't back off the boost!
At this point, my PT has surpassed what Bill Hahn had estimated I would get from a stage I system. The large intercooler is part of the reason. It "allows" me to run more boost, without the death rattels of detonation. In talking with Hahn, he feels I should go ahead and finish the conversion to a full stage two, with larger injectors and an electronic boost controler. This will allow me to get back down to a "low earth orbit" with my fuel pressures, (55-95lbs).
You know what I'm thinking, .. if I can take .5 sec off my time and add a few mph, like the Neon results, ...bla-bla-bla!!! We'll see next week I hope. A fully dressed PT in the mid 14s' at almost 100 mph,!?... That would be cool! Check ya later Bob |
