I don't buy that this could be at all power robbing. This has to be a pinhole and under such low pressure I can't be putting that much on the fire.
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I don't buy that this could be at all power robbing. This has to be a pinhole and under such low pressure I can't be putting that much on the fire.
Do you notice a major throttle position difference between the two engines?
I'm curious on what they make on the Dyno ? Ed Champion said 700 to me when the boat was listed for sale
Everything else being said, I'm still thinking there is an issue with the setup or bottom. The huge differences in speed with 2" extension in or out, and the two different prop sets, makes me think there has to be a trim, bottom, drive lineup, prop configuration, etc issue as the main problem. He's not even getting the same speeds as the tests when the test boats had stock engines.....
The intercooler could be putting out the fire, but not necessarily.
You checked everything with your ignition as well? Timing? We've had a rev limiter go bad in the MSD ignitions before. It was very tough to read because the motor with the good ignition didn't have enough power at the time to pull that many more rr's than the one with the bad ignition.
If the pinhole were hurting that much you don't think the throttle positions would be drastically different when in sync?
Throttle positions are identical. Gonna pull the other cooler Sunday and pressure test that one too.
OK so the second intercooler is leaking even worse. I put 10 psi on the water side and it leaks out almost immediately. Motor is out so gonna do a leakdown on that next week and see what shows up. I have 2 new intercoolers from Frozen Boost that I'm gonna use to dyno.
I guess that's good news, kinda.....
Don't forget to check the bottom and the drive height though. You would be shocked at how much speed is scrubbed by very slight indent area.
I had very good luck with my Procharged 500EFI's. Hang in there and you will get all the kinks worked out.
There might be more then one problem at a time also
Ran an 8 foot straightedge all along the bottom today and there's no hook. Its completely flat all the way back. I'll get drive height later this week. Doing leakdown this week too.
Cool
That is a good thing. Black Thunder never had the big problems some mfg's did with pulling the hulls too quickly from the mold, but you never know.
So here's another update. Pulled the 1st motor and did leak down and compression test. Ends up there is 150 psi in 2 cylinders, 125 in 2 others and only 110-115 in the other 4, so I'm guessing that's my issue. Didn't bother to dyno after finding these results. Pulled the 2nd motor and that ones in the shop now too. While they're out we're gonna do complete rebuilds - 540's. It'll be interesting to see how these were actually "rebuilt" before I bought it or if they were done at all. We'll know more in the next week or so.
540's with the blowers? Should be a strong runner then.
Any updates to your engine builds?
Curious what cams you were running? When dynod they made 760hp @5lbs on Dyno headers and no accy. I just pulled mine out to go to a cam more favorable for NA.
Compression readings were 183-194
The cams I pulled were:
270/276 adv.
.510 lift
110 LSA
Comp grind HR270
Pretty sure the cams were just stock cams. I dont think much was done to these motors previously. They were in pretty bad shape.