OK, this is probably a really dumb question, but is it bad to rev the engine? I'm not talking about going over the redline, but just to maybe 4k so that when I let off it'll backfire. (sounds soooo cool) I know it can't be good, but does it hurt?

 

I wouldn't go revvin to 4k when first starting the car. I doubt every now and then will kill it.

 

free revvin will hurt it after a while.....my buddy has a 86 monte ss and every day hed rev it 5500 and let off i was like dude what a re u doing...he said ''its a chevy you cant break it"....while id love to beleive this its false...when u free rev it theres no load on the motor when the r's fall...and its possible to spin a bearing....

when u rev to lets say 4 grand and slowly bring them back down then nothing will be hurt

 

Backfire or back off??? big difference.

 

yeah it's really bad to do and it doesn't matter how cool it sounds. most people tend to believe an engine breaks because too much load was put on it, but the oppisate is more often the case, too much load was removed from it, that is after the parts are spinning at a certin rate and you remove the load they still want to continue spinning at the speed they were, that's when rod bolts break. or on the case of the little B&S engines i used on my karts the rod comes out of the case.

 

Hmm, guess all my brother's past cars will only have a few miles left on them then, lol.

 

Loaded or not, I wouldn't do it until the oil is sufficiently warm and flowing, and all the parts are at operating temperature to minimze clearance differences - unless you like rebuilding bottom ends and replacing timing chains in your spare time.

 

and
I guess you should never release the throttle then. Like after accelerating in a gear, you push the clutch and release the throttle, the motor is free spinning with no load then. I guess you shouldn't do that? Or engine brake down a hill in a low gear? C'mon, now.

I don't agree that it's bad for an engine to free rev it. Yes it put's stress and wear on parts, but they are designed for that. You won't throw a rod or spin a bearing by revving it to 4000 RPM. Although the original poster didn't mention anything about revving a cold engine, it should be obvious that that would be bad, as is any heavy use before it warms thoroughly. Once warmed up, it is fine to rev.

 

I uesd to rev my 355 TPI all the time no problems esp when I did some work to it to see how its running etc.

My freind has a Baccacuda 340 that has been out of service for ever but he would go and rev his 340 up all the time then 1 day boom. He blew the **** up real bad.

But hey its a mopar not a chevy.

 

Yeah, i ment when it had warmed up. Even I know cold engine=death when put under strain. I just did't know if it was bad to do it when it had warmed up. However, I still don't understand how no load is worse on parts than with load. Its all spinning at the same speed, right?