Chrysler Repair: rev-limiter?, plymouth sundance, coolant temp

Question
QUESTION: I have a 91 Plymouth Sundance and at around 3000 rpm the engine sounds like it's hitting a rev-limiter.  The car is actually a fwd race car, so a bunch of the wiring is gone, unfortunately I bought it this way so I don't know what all has been done to it.  How can this be fixed?

ANSWER: Hi Doug,
Without knowing which wiring is 'gone' it is hard to know. If it had to do with the engine then all that I can think of is to talk to whoever owned it to find out in what ways the stock set up was changed both as to wiring and to modules/sensors/settings.
What engine is in it? How has it been modified? I have the stock wiring diagrams for the car and they cover about 80 pages. I can xerox copy and postal mail those to you. It cost me about 10 cents a side and with postage it would be about $10 to copy and mail. Other than that I can't thing of a rev limiting device unless there were a rotor that disconnects the spark centrifically, but I doubt it was used on such a race vehicle. It could be that your catalytic converter is plugging up, which will cause this, or perhaps your fuel filter is clogged or the fuel pressure is below spec. Those are the common cause of high end restriction. The compression of the cylinders would probably also be a relevant thing to know. Also checking the setting of timing would possibly explain why you have this limitation. It should be 12 BTDC at idle with the coolant temp sensor disconnected. Let me know which engine is in it if you write back.
Roland

---------- FOLLOW-UP ----------

QUESTION: Roland,

Thanks for the response.  It has a 2.2L 4cyl.  The car is completely stock, just the wiring for the lights (tail & head are gone.

Any more help?


Thank you very much!

Answer
Hi Doug,
No, I can't think of anything other than the items that I mentionned in my first response. So take a look into those and see what you find. I would suspect the catalytic converter or muffler of being partially obstructed. But check the timing and the fuel pressure/filter too. Compression would be an overall assessment of the piston rings and valves.
Roland
Roland