Reply With QuoteRun it.
OK guys, need opinion,
Blown alc inj 505 bbc, started and warmed up best i could, still less than 100 degrees after idiling out 5 gal of alcohol at 1500 rpm. block just warm to the touch.
did leak down, results #1 18% #2 8%
#3 7% #4 10%
#5 6% #6 14%
#7 18% #8 10%
cranking compression all cyls 140# except#6 130# and #1 130#
motor has about 12 1/4 mile passes on it
tear down or not???????
Thanks
Run it.
Teardown???, if you got good oil pressure, run the shit out of it!!.......
your running alcohol, that is common to wash the cylinders clean of any oil because of the volume of fuel that is in the cylinders. sounds like your real rich at idle and just off. are you running water in the block or just in the heads or any at all? If yur really conserned about getting heat in the motor before a pass than run 110 octane fuel through it and be sure to shut your shutoff valve way down the lean the fuel mixture or run it on alc and shut the fuel down to lean on it this will cause a higher rpm and build up heat do to it being lean. I'm assuming its blown and injected??
yes, it is inj, and i'm sure it is pretty fat. oil pressure is excellent 90 idiling over 120 quick blip of throttle.
another friend of mine mentioned the cyl wall wash down possibility.
hulshot, im going to try the gas warm up thing next time. seems like no matter how hard i run that motor it will never get over 140 degrees. when im waiting at the in ramp i always fill the block with a small elec pump, turn it off, and go to the holding rope, make pass, and drive back to trailer still with no temp.
yes i do seem to have quite a bit of oil contamination. use castrol 20/50 oil, always have, but if youre familiar with that stuff it always looks like a milky mess at change time anyway. still have had good luck with it. change after every weekend of racing.
thanks for youre input. hoping to get away without a rebuild.
by the way, the boat is the red and blue kurtis hydro in the "race boat gallery" section under "drag boats" in the picture area.
if u will lean it out with the shut down and build the temp to 180 it will run alot better . and the milk oil problem will go away alot.. boss has an alcohol drag car..
it makes alot more horsepower around 180 degrees.. up to 210 degrees..... above 210 power starts to fall off again...
Where is it leaking rings or valves? What kind of rings did you use? I guess you used 100 PSI to check it.
[This message has been edited by Infomaniac (edited March 24, 2002).]
Info,
All of the leakage was in to the pan, checked it with a sthescope and could hear it plain as day.
Has speed pro file fit rings. Fresh hone, and best i can remember had .026 end gap. What ever Speed Pro recommended for blown applications.
Yes did use 100PSI of air.
Info, I have always valued your opionion on here, what would you do?
Those cyls. are still good. When they reach 30% leakage then think about freshening up the engine. Consider you are leaking a cold engine that has been fuel washed. If you still have doubts then do a "wet" test. Don't put too much stock in a leak-down test, rings work best when the engine is running.
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