It may also be the bolts stretching. And congrats, that is amazing power out of an old Y.

Paul, There's nothing much you can do. Either it stands the boost or not... Crank is still the same old forged truck crank and Callies Compstar rods should stand at least 800 hp as they advertise. Well, we went a little over that... 292 +.030  block has no cement and main caps are stock with stock bolts and that may be the issue with losing oil pressure. What I think is that under heavy load the caps deform and let the oil flow out of bearings. That's definitely not a good thing and for next block we have to change better caps and put that girdle on what is almost done already. We just haven't needed it yet... For now all we can do is chance arp studs to main caps.

 Seppo from Järvenpää, Finland
www.hollowheads.net (just click the hole in the head to proceed)

Wow!! Congratulations!  Not only are the numbers almost un believable, but what are you doing to keep that engine together?!


Paul

John, you're correct with that oil pressure issue. It has to be issue with crank case pressure under heavy load. Vacuum pump or do you have any other solution? Dry sump would be great with three or five stages.

 Seppo from Järvenpää, Finland
www.hollowheads.net (just click the hole in the head to proceed)

The numbers look great. Good job.   It looks like oil pressure is falling form 70 to 25 psi during the run.  Hopefully you guys have a handle on that.  Look forward to seeing more videos.



http://ford-y-block.com 

20 miles east of San Diego, 20 miles north of Mexico

BTW. Advance was 38 degrees in 32 lbs boost at 6300 RPM / maximum power point.
Dynoman thinked, under that engine cant even run without popping.

E85 is quite hard to get knocking.


Hyvinkää, FI

John did the heads and piston domes I have now.

Cliff

Imagine what that set up would give with Mummerts latest heads ???

 Seppo from Järvenpää, Finland
www.hollowheads.net (just click the hole in the head to proceed)

GOOD JOB, I'm doing all I can to make 625 HP form 320 CID with iron heads (don't know if i'll make it).

Cliff

Thanks Ted. That 300 hp estimate can well be true and maybe even little high as our compression ratio is well under 8.5. But still, those iron heads still stand strong! And, we hit that over 900 hp many times yesterday.

 Seppo from Järvenpää, Finland
www.hollowheads.net (just click the hole in the head to proceed)