PDA

View Full Version : over revving the engine



hgrewal
12-26-2006, 09:47 PM
first off the car starts up runs just fine as it did before but i m just little paranoid since i last went to the track. it was my first day on the track with this car and since there is no rev limiter i noticed that i was shifting somewhat late ... late = around 7000 - 7500 rpm, whereas the stock redline starts around 6500... the engine is not totally stock it is overbored and balanced.

first thing on my to do list is to install a shift light but for now i am just looking for some info in terms of what kind of damage can be caused by over revving and in my case since i have not noticed anything out of the ordinary even after the event is there something that might have been damaged or i should be wary off?

thanks in advance.

its66
12-26-2006, 09:55 PM
Harry,
The first thing that usually happens when you over rev one of these is you bend the 4 exhaust valves. If it still idles fine and pulls good vacuum at idle, the valves are probably ok. I guess it is possible to hurt the bottom end also-causing premature wear on the rod bearings. (doubtful though) FWIW, I shifted mine at 6200-6400. I didn't see much advantage to twisting it up higher than that. (HP peak was at 5900)

hgrewal
12-26-2006, 10:07 PM
Jim,
thanks for the response.
as for idling now i have noticed that it does idle tiny bit higher then it did before... its actually around 1k now and before it was less then 1k maybe around 800. but the idle is very stable as it does not fluctuate up and down. i am thinking about doing a compression test as well. as for shifting at higher rpm the car still seemed to pull around 7000 and not having the shift light doesn't help either.

thanks

joeg
12-27-2006, 07:33 AM
Don't worry about it! You are going to have to rebuild a motor someday, regardless.

Get your shift light, however.

The higher idle is not a symptom of anything horrible.

Noises would be a real symptom.

Generally overrevving will affect the upper end components first. After that it would be bottom end--rod bolts and rods/ crank--but you would know that via a ventillated block.