BBC 509cid tunnel ram efi build.
#41
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From: Finland
Actually i have no doubts, i think i am good with 9.8 or 10 to 1, DCR is under 8 to 1 with both, even if i advance the cam 8 degrees. This is calculated using the duration at 0.006" lift. Using the 050" duration and adding 15dg to intake closing point gives 8.2 with 8dg cam advance.
#42
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From: SW Ohio
The one video thats out there of racin jason at loto running 85 on sunday at shootout i think 3 years was the MPI 509 engine I dynoed and tuned that made 620/620 here. The announcer calls it a velocity in the video because he had a velocity the year before or something.
There was one I found of a 9yo kid at the wheel, dad standing behind him with his hand on the throttle, and the camera glanced down at the GPS at ~85. The description mentioned a "Built" engine, but wither I don't remember what it was, or it didn't specify. I did see the one you refer to, though. I was confused by the announcer, but now I get it.
At the end of the day, we see that the hull is good for it, with sufficient power. 85 is my goal. It will have to wait for time to refresh the 496, and I'll replace the pistons and bump the boost from the ProCharger. I'll have to upgrade the outdrive, as well, to handle the additional power. This is probably all probably a pipe dream, as the budget office is.... "satisfied".... with 77 and is pretty well convinced her knuckles are already white enough.

Thanks. Brad.
#43
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From: Finland
Looking for valve springs, Ron calls for 180-200lbs @ seat, and no more than 500lbs open. 2.3"/1.88", 11/32 stem valves. going set the rev limiter to 6000rpm. Would like to use my comp 741-16 steel retainers if possible? Those are heavy tough.
#45
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From: Finland
Starting to modify the intake. First we machine the holes for injector bungs, injector bungs are made from 40mm thick aluminum rod, and we try to fill the the intake port with the bungs, so we dont have to fill the port by welding that much. This intake is rec port, that will be modified to match flotek r-oval runner.




#46
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#47
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Joined: Aug 2019
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From: BC
The compressed air or F/A mixture will behave the same as NA for the most part.
Not my words...from Darrin Morgan.
290 Floteks have a smaller chamber, and roval intake ports. They flow very similar to the 315/317cc heads. Likely only notice a diff at WOT, where the engine may spend 5% of total run time.







