Blown Engine.......What do you think happened?

[usafracer]

60# hot when racing 25-30 at idle when I come off the track. 100 shows on the same motor never freshened and it finally let go last weekend. Bearings look good but something in the fuel system went south and motor ran lean and burned a piston and valve.

Changed oil every three shows with delo 400 15-40.

[Egoracing]

HOLY CRAP!!! We always shot for 10 PSI per 100 RPM with regular oils and between 2-Psi per 100 RPM with Synthetic race oils. Do you have any idea how much power you are using up trying to pump 100 psi, not to mention that the pressure on the distributor is going to have the thing scattering spark all over the place and killing ignition timing.

[dirty white boy]

HOLY CRAP!!! We always shot for 10 PSI per 100 RPM with regular oils and between 2-Psi per 100 RPM with Synthetic race oils. Do you have any idea how much power you are using up trying to pump 100 psi, not to mention that the pressure on the distributor is going to have the thing scattering spark all over the place and killing ignition timing.

100lbs with rod cap lose!! to much oil will ruin barrings as fast as no oil will anything over 70lbs hot is washing the barrings away,...lernt that on 1st motor i ever built!

[Mosidebite]

60 pounds at start up....45-50 pounds at 8500. Dennis Wells has sold me on volume not pressure.

[dirtbandit]

As expected, the engine builder did not stand behind the motor. Had all kinds of excuses. Then said the cap screws were old and probably stretched.....( I would think he would have noticed that when assembling the engine and call and make the suggestion that they be replaced.

Engine didnt have 100psi of oil pressure. Cold start up had 65psi and after running had 28psi.

[merc123]

why in the hell would you have 100# oil pressure ? how do you keep rear main seals in it ? you never need anything over 80, and i normally never run anything over 70.... 30# hot at idle after a race is fine

Not like my pump has a dial on it... It's just what the gauge reads. I didn't build the engine... It's down to about 45 to 50 after the race though.