Between rebuilds?

[W2Racing09]

How long can you go between rebuilds? If you run 15-20 races per year and not running in an ultra competitive tour? I see engines for sale that say 40-50 nights since refresh, which seems like quite a bit, but I know these motors hold up well.

Thanks,
Jeff.

[Matt49]

Count laps instead of races and you'll have a much clearer picture of how many pulls the motor has really gone through.
That being said, 2000 laps on a crate motor with no performance drop off is not unheard of. Just keep the oil fresh and stay on top of routine maintenance of the valve train and you should be good to go.

[parocket]

I went 3100 laps on an asphalt 604, when we switched to dirt. The motor was still running good but needed to be verified for Fastrak. It had good compression number before rebuild and dynoed as expected, after the rebuild it had a little better compression numbers on leak down but dyno number really no different.

[brad hibbard]

we have topped the 500 number on rebuilds and still cannot see a clear pattern for a scheduled rebuild

when you do a good job on your maintenance program---keep the rpm and timing witin limits and water temperatures in the 200 or less range----it will last a very long time but it only takes one event where one of the mentioned areas is exceeded or ignored and then you are down on power

we consatntly here "it only got hot once"-----
i am not saying every time your engine gets hot you need a rebuild but everytime it gets hot it does take some life away and it is very possible depending on how hot and what you did when it was hot that it could be hurt where it will be down on power.

Brad

[PushinTheLimit]

Brad, check your PM's and get back with me when you have a chance... thanks!

[GRT62]

We had a 602 in a late model had over 5000 laps on it got it up to 250 on water temp one night winning our first ever feature race and it was done after that blew the head gasket but the motor was strong up to that point ran up front with limited lates and 604s

[cloverleaf]

Brad, so anything over 200 on water temperature is considered bad. I was always told that the motor didn't start making power until the 210 or 215 area. What about oil temperature, what would you consider a max tempo before hurting the motor. Thanks in advance.

[brad hibbard]

NO---- 200 on the water is not considered bad----I don't even panic with 230 BUT if your target temperature is over 200 for normal operation then exceeding the boiling point on a hard run or plugged rad is potential for failure.

I have not seen much if any power benefit to high water temps (over 200)

my suggestion on target water temps is 180 to 200 and then on them hard runs or when you pick up some debris in the rad and the temp goes to 230 you don't have to call your engine builder

but if you want to target your temp at 215 to 220 (like many do) and you get a little plugged up one night now all of a sudden your at 260 and then you do have a problem

oil temps SHOULD be targeted over 220 for clean and effective oil life
if the oil is run under 200 it will not evaporate the moisture however oil temps over 260 will cut power

Brad