getrdunn

iTrader: (7)

Was wondering the same. Valako knows me all to well and very adamant about staying in the 240-246 (max) range to run at 6,300 with his ported heads. He knows his heads very well and can't argue with him but it's amazing how the cam tech guys advising me to be in the 256-262 range. Are they trying to get me closer to peak torque? Just guessing!

A bit confusing but I like to listen to my head guy. He doesn't want me to sacrifice velocity I'm pretty certain and to optimize HP at said rpm. I rember Mild Thunder using several different grinds in a 540 platform simulation a few years back. But with a stock afr 325 head if I recall. Was a good informative thread he took the time for all to see. What's kinda funny when I dropped my rotating assemblies off at more power racing yesterday for balancing they are still using mostly the old school 741, 651, and 881 crane shelf grinds on the majority of their builds. Dick (owner) said the few customers that bring in their own custom grinds for their builds fell on their face and end up swapping out to old school. Hard to believe and I'm sure doesn't apply to all.

dunnitagain

Mark and Kirk at Bullet are damn good , and price and turn around are excellent.

TomR

I can't tell from the cam card but if the cam has Asymmetrical lobes you have to consider this when degreeing in the cam. Instead of checking @ .050 you check at .020 from max lift.

getrdunn

iTrader: (7)

Hmmm! You’d think Note: on cam card. Good info regardless.

getrdunn

iTrader: (7)

Did you ever go aftermarket heads? Seems like I recall you had ported 088's and a 252/252-652/652 and high elevation but I may very well be incorrect... Just what I recall from years ago. Either way keep us posted with your dyno session and wish you the best of luck.

boostbros

we used ported cast iron darts used a crane dynoed at 807 but was a terrible combo it loaded up had a spike in power getting on plane from bogging to snapping to life kinda like a dirt bike the bullet really tamed everything out and winds up much higher i did not dyno the bullet cam

Tahoe540

I did measure at .020 and was the same. I did read about the asymmetrical lobes.

This motor now has BB2xtra CNC heads with Jesel shaft rockers. It also has a matching brodix intake.

I also got a set of Johnson lifters from Teague.

I think the heads are too big for this motor but it is what I have.

This motor is going into a jet boat I bought. I am running an A impeller and from the HP chart it should run 5800-6000 rpm.

I want to have it dyno'd after I am done building it.

getrdunn

iTrader: (7)

Just curious if you dyno'd yet? Hope all works well with close to meeting your goals. Might need to modify your impeller a bit to get your rpm's up a bit more. Be nice to see that turn around 6,500. Would be fun to bring it down closer to sea level for a weekend.
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