Turbo Dodge Forums banner
1 - 4 of 4 Posts

·
Registered
Joined
·
1 Posts
Discussion Starter · #1 ·
Here we go. I went to the NHRA Division 4 race this weekend, at the Motorplex in Ennis, Texas. Weather was great. Entered our little minivan in Stock Eliminator. We added a little weight to run D/FS. D is 19 pounds per
the "factored horsepower" rating of 175HP. Hot dog, 14.509 right off the trailer. And at 3530 pounds, no less. "Hey fellas, that could be a record if you can back it up", we're told. COOL! Second pass, an easy 14.560. Weigh again and go through fuel check then we'll come tear you down. Great. Minimum weight is 19 x 175, plus 170 pounds for a driver = 3495.
Fuel came from a fresh drum of VP C-10, unleaded. All is A-OK, right?

All right, get the head off that thing, separate the manifolds and then I'll get you to pull a pair valves out. After a 2 hour thrash... the pistons are illegal. WHAT? Illegal how? The NHRA 1989 Technical Specification Guide calls for the "dish" in the piston to be .325 deep. We set the National Record and were Low Qualifier, for all of Stock, with a totally stock minivan and now we're disqualified! Dude.

Back at the shop, we measured a 1989 piston out of a blown up turbo 2.5 stick shift minivan and a 1989 turbo 2.5 piston out of our "spare" wrecking yard motor and they're all in the .280 range. What the #%* is going on here. Was there a 2.5 Turbo piston ever made the had a .325 dish ?!?!? Help. I'll buy a MOPAR replacement 2.5 turbo piston, if it's NIB, with a legible part number, to send to NHRA. I'd bet it doesn't have a .325 dish.

Racing: I guess if it was easy... everybody would be doing it. Kirk
 

·
Registered
Joined
·
2,602 Posts
I think you got hosed. I've been torn down twice, but never to the piston. Once, they had me pull the intake, exhaust, throttle and turbo for inspection. Once, the only checked out the throttle bore and then the rest of the car.

I have OEM Mahle pistons in mine, too. I just checked the NHRA BP specs and they do show a 0.325 dish. Which I don't believe is correct. If the actual stock parts are a 0.280" dish, how could they be illegal? The OEM pistons have a pentastar on them, it should be obvious they are OEM. You should have had the tech guys call Glendora and sort it out before they tossed you...
 
1 - 4 of 4 Posts
Top