What is the max (safest) rpm i could rev on a 95mm x 81.5mm motor?
ok here's the specs:
Eagle 95mm crank
Eagle long rods
Weisco pistons
Race PNP B16 head
S2 Stage 2 cams n valvetrain
BDL 70mm TB

 

Heat is the primary obstacle to higher RPM's, with balance and timing not far behind. Forged parts transfer heat better than cast parts but other than that, you haven't really addressed these issues enough to bring up the redline that much. Also, the new pistons are now transferring heat more efficiently to a slightly thinner and weaker cylinder wall. Some suggestions to help make higher RPM's safer/possible: Have the bottom end balanced. Replace the stock balancer with a performance piece. Upgrade your ignition. Install an oil cooler. Replace/upgrade your radiator. Scrub the coolant channels around the sleeves with a small wire tubing brush to remove dirt and corrosion, blow the dust out and rinse well. Flush the coolant system. Make sure you're running a newish thermostat. Always use a quality full synthetic. Upgrade ECU & tune. Of course, there are endless little tricks to remove heat or make the motor run more accurately.

 

And all this time i thought it was piston speed and and rod angle, like every sngine design book or paper says. To the OP 8400 RPM. and that is pushing it.

 

i don't think you can rev very high. that's why honda made high rev engine with shorter strock.

 

The reasons why piston speed is a factor are because it causes heat and changes timing difficulty dufus. Try less reading and more thinking.

 

well iv got a b18c1 thats got pro i-beam rods type r pystons polished crank and ported polished head with skunk 2 build on the head and i have a chiped ecu and the rev limit is set at 10 grand. i have takn it up to 10g a number of times and no problems..........yet!

 

and it makes power up that high does it? Just because you can do something and get away with it doesn't mean you should.


you're hilarious....you have no idea what you're talking about do you.

 

Really, i did not know that. I thought heat rejection was done gy the cooling system and oil system, I will give Prof. Blair a call. LOL

 

[QUOTE=00Red_SiR;38787827]and it makes power up that high does it? Just because you can do something and get away with it doesn't mean you should.

lol no but its fun

 

I honestly I dont think your motor will make power beyond 85000 rpm's. If it was the other way around, you know big bore and a short stroke then i would be asking this question.

One question, Why are you going with this bore and stroke setup? I have seen way better results on a dyno out of a 84mm bore with stock stroke motor.

 

You mean friction creates more heat than combustion.

Lol, can you hold that rpm for 1 minute?

I will call Profs Heywood, Turns, and Wesseling and notify them they are wrong. Also, I think I need to talk with the people at Virtual 4 Stroke and let them know about this new ideal.

 

Maybe WE and those other dufus's you refered to can learn something. LOL Now I know why NASCAR 358 ci engines have less stroke than a GSR, it was heat. LOL

 

So you have an 87.2mm stroke, and you're trying to make a comparison to a 95mm stroke?