SpeedPro Tuning

[John Walker]

Valid question Bob.  They truck is pretty well modified currently.  I enjoy 
drag racing, which is the truck's primary use and a nice weekend drive.  So 
basically, it is a toy. :) I'm currrently running an ATI P600H supercharger 
with Intercooler, Precision Industries 3400 stall converter, 28" E/T 
streets, headers & exhaust, MSD 6BTM and Blaster 3, Trans-Go shift kit and a 
few other goodies.  Electric fan and 14psi are coming with the speedpro.  I 
reached a big hurdle in the project after I put in the converter and E/T 
streets.  When I stall the truck up to about 2000K rpm (or anywhere between 
1400 and 3000) and try to flash the converter and launch hard, the truck 
just flatlines.  I verified that the timing was infact falling rapidly 
towards 0 degrees when this happens.  I've spoken with one other person that 
is researching the same problem.  It appears to be some form of torque 
management (i.e. too much engine speed, no vehicle speed cut spark advance) 
or something to that effect.  I have tried many fixes but nothing has 
worked. On the flip side...an off idle launch around 800rpm will send the 
E/T streets into smoke. Unfortunatelly I have spoke to many people including 
a couple of active Chrysler race teams, computer programmers and no one can 
confirm the existance of torque management or the problem.  I have made 
attempts to acquire an internal engineers contact info...but have had no 
luck.

So...enter SpeedPro.  My philosophy is that if the computer is making an 
active decision to cut timing....then SpeedPro will cure the problem since 
it will be making all Fuel and Timing decisions.  I researched AutoTronic, 
Hal-Tech, Electromotive, SpeedPro, and Accell before making my final 
decision.  SpeedPro was proven and the less intrusive harness was available. 
  Besides the cost, I think it will work well.  So...if I can race 
again...i've succeded.  But a modest horsepower gain should be an added 
bonus.  Plus heads and cam are next and that would surely throw the stock 
computer for a loop.  Their are also a few hiccups the the Supercharger has 
introduced to the truck that the SpeedPro will fix (stock 1-bar incorrectly 
reads 30" of vaccum under boost causing a surge in part throttle accel).  
Plus I can ditch the FMU and run a constant fuel pressure and change pulse 
width with boost and rpm.

If your interested in more details check out my website at 
http://www.DakotaRacing.com

later,

John


>From: "Bob Wooten" <r71chevy at earthlink.net>
>Reply-To: diy_efi at diy-efi.org
>To: <diy_efi at diy-efi.org>
>Subject: RE: SpeedPro Tuning
>Date: Mon, 18 Jun 2001 20:04:20 -0700
>
>John,
>
>If you don't mind me asking why go through all the hassle for 20 HP on a
>truck?  are you planning on putting a blower on it, or NOS or is this just 
>a
>toy?  just curious is all.
>
>BW
>
><SNIP>
>
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