Originally Posted by Kingtal0n

I agree, 3k is no problem. 3k is 65mph. thats exactly where I told him to stay, well done good job. hes tryin to hit 3.5-4k continuously, 75-88mph. that IS a problem. too much friction, clearances are too tight for it. too much heat. rod bearing clearance on that engine is .0008" iirc. Turbine is too small. Once again, there is a reason they did not bring this engine to the USA and it has, in part, to do with climate.

Originally Posted by Kingtal0n

His problem is that redtops are not designed to be at 3600RPM on the highway in Florida weather; thats it. the turbine is too small and the gearing is too short for it. If you disconnect the turbine it will no longer overheat because thats where all the heat is coming from. otherwise, I told him to just drive 65MPH @ 3000rpm because thats where engine vacuum is 10" about as low as you want to go for steady highway speeds.

At 80MPH and 3600RPM the vacuum is around 3"-5" the engine is damn near in boost and it gets hot after 50 miles on that T-25, yeah.

the issue here is not so much cooling as the fact the engine should not be sitting at 3500+RPM for any length of time, regardless of whether it overheats or not. period.