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512 BBM-- How much power???

Posted By: qwkmopardan

512 BBM-- How much power??? - 12/15/17 08:29 AM

Just finished a friends 512 BBM. Indy block--4.375 bore--4.25 stroke--15 to 1 CR--Indy-1 Heads--titanium valves--385 max flow on intake--Ultradyne .690" lift 281* at .050 roller cam--300# seat and 700# open spring pressure--T&D single shaft rockers--Indy single dominator intake--1050 alcohol dominator carb--Charlies dragster oil pan. It has a fairly heavy Crower crankshaft. We are expecting it to cross finish line at 7400-1/4 mile. How much aprox. power? I am thinking close to 900 horsepower. No $$$$ in his budget for Dyno.

Engine going in a car that weighs 2250# with driver. A mutt. 1963 split window Corvette. What E.T. 1/4 mile???? 2 speed trans. and 4.10 gears with 16X33 tires--2250# with driver
Posted By: Dave Hall

Re: 512 BBM-- How much power??? - 12/15/17 08:52 AM

I'm not sure it makes 900 at 7,400. I would venture a guess of 8.60's in a light car like that. Seems like the cam should be bigger??? I have a cam like that in my S/ST car with OOTB -1's. It would probably go a lot quicker with a 4.7 something gear. Should be pushing 160 mph though. My twocents.
Posted By: qwkmopardan

Re: 512 BBM-- How much power??? - 12/15/17 09:02 AM

Car went 8.60s with this engine at 12 to 1 CR and a 560" lift flat tappet cam. Crossed at 6900 1/4 mile.

Cam was bigger. 285 at .050 but someone milled the heads so far to get 64cc that valve pockets couldn't be cut deeper so we had to kill some duration to get it to all fit. Have .065 intake valve to piston now and piston is .200" thick at valve pocket.
Posted By: Dave Hall

Re: 512 BBM-- How much power??? - 12/15/17 09:04 AM

Cool! So much for what I know... up What's your best guess?
Posted By: qwkmopardan

Re: 512 BBM-- How much power??? - 12/15/17 09:12 AM

We are hoping for .4x improvement 1/4 mile and .3x 1/8th mile. Went 5.5s 1/8th mile and 8.6s 1/4 mile. Maybe 75/80 more HP. Heads had some minor update to porting also.
Posted By: rb446

Re: 512 BBM-- How much power??? - 12/15/17 03:59 PM

According to Wallace...at 2250 at the line and your gearing/tyres>
8.60's@159mph is 700hp on the day, ....@780hp it would be
60 Foot E.T. : 1.15
1/8 Mile E.T. : 5.23
1/8 Mile Trap Speed : 129.92
1/4 Mile E.T. : 8.29
1/4 Mile Trap Speed : 162
1/4 Mile Trap RPM : 6,751+slip

However from my experience with very light cars it tends to mess up the Wallace calcs/numbers somewhat for reasonable accuracy.

900hp would be>

60 Foot E.T. : 1.10
1/8 Mile E.T. : 4.99
1/8 Mile Trap Speed : 136.26
1/4 Mile E.T. : 7.91
1/4 Mile Trap Speed : 169
1/4 Mile Trap RPM : 7,081+

Posted By: AndyF

Re: 512 BBM-- How much power??? - 12/15/17 05:49 PM

Hard to say on the power, could be 800 hp with those parts or it could be 900 hp. In my experience with engines like that it comes down to details. Porting the intake is worth 25 to 30 hp, running more rocker ratio and more valve lift is worth some power, Jesel belt drive and belt driven distributor helps out, big oil pan helps the power, correct headers help the power, vacuum pump helps, gas ported pistons help, etc.
Posted By: gregsdart

Re: 512 BBM-- How much power??? - 12/15/17 08:20 PM

I have -1 ported heads ,15/1 comp 528 cubes, alky terminater injection, cam is a Jones 285/296/114 with 8.70 intake lift, .830 exhaust lift, 33 x15 inch bias slicks with a 3 speed T F , and 4.56 gears. At 2000 DA I average 8.90 at 150 in a 3065 lb car with driver. Trap rpm is 7400, I shift at 7450.
Posted By: Cab_Burge

Re: 512 BBM-- How much power??? - 12/15/17 08:34 PM

Originally Posted By qwkmopardan
Just finished a friends 512 BBM. Indy block--4.375 bore--4.25 stroke--15 to 1 CR--Indy-1 Heads--titanium valves--385 max flow on intake--Ultradyne .690" lift 281* at .050 roller cam--300# seat and 700# open spring pressure--T&D single shaft rockers--Indy single dominator intake--1050 alcohol dominator carb--Charlies dragster oil pan. It has a fairly heavy Crower crankshaft. We are expecting it to cross finish line at 7400-1/4 mile. How much aprox. power? I am thinking close to 900 horsepower. No $$$$ in his budget for Dyno.
Why not find, earn, do anything, to get the money needed to put it on the dyno to help tune it before putting it in the car? confused work
I've dyno tested a similar bracket race motor (526 C.I. 4.375x4.375 stroke, RB with 12.8 to 1 comp. ratio on 110 race gas) and a 518 CI low deck 10.78 to 1 comp. ratio pump gas motor, with the same set of CNC ported 440-1 heads with 2.25 intake valves. the race motor made right at 850 HP on 110 octane race gas and the smaller motor made 775 HP on the pump gas motor on 92 octane Oregon pump swill compared to a set of SR with M.W intake ports and the 2.19 intake valve, both sets of heads had the same 76.0 CC on the combustion chambers, same headers and so on with no other changes than swapping the heads shruggy
On your deal I wouldn't be a bit surprised to see over 900 HP at or above 7500 RPM and a little less torque shruggy
I've never ran straight Methanol alcholol so I have no idea what it is worth as far as HP and torque compared to race gas, I did test one other 511 C.I. low deck bracket race motor on race gas and then on Oregon pump E85, which tested to be E89, that motor lost 11 HP on that pump E85 but made 15 ft. Lbs more torque than on race gas after jetting both carbs. to get the best results on both combinations work shruggy
Posted By: HardcoreB

Re: 512 BBM-- How much power??? - 12/15/17 09:07 PM

Your builds tend to surprise many of us (in the best possible way). I have seen a Bob Book built -1 motor make a touch over 1000 HP and the performance backed it up. But that had a 4.5" bore or larger and on Q fuel. "Yours" would like more lift for sure and the other bottleneck I feel is the carb is 'small'. with the info given assuming you did 90% of the parts selection I would give a generous guess of between 875 and 9.
Posted By: ChrgrCuda

Re: 512 BBM-- How much power??? - 12/15/17 10:39 PM

Originally Posted By qwkmopardan
Just finished a friends 512 BBM. Indy block--4.375 bore--4.25 stroke--15 to 1 CR--Indy-1 Heads--titanium valves--385 max flow on intake--Ultradyne .690" lift 281* at .050 roller cam--300# seat and 700# open spring pressure--T&D single shaft rockers--Indy single dominator intake--1050 alcohol dominator carb--Charlies dragster oil pan. It has a fairly heavy Crower crankshaft. We are expecting it to cross finish line at 7400-1/4 mile. How much aprox. power? I am thinking close to 900 horsepower. No $$$$ in his budget for Dyno.

Engine going in a car that weighs 2250# with driver. A mutt. 1963 split window Corvette. What E.T. 1/4 mile???? 2 speed trans. and 4.10 gears with 16X33 tires--2250# with driver


Man I'd love to see some pics of that BBM in a 63 Vette!! Give my GM friends heart attacks. LMAO!!
Posted By: Dave Hall

Re: 512 BBM-- How much power??? - 12/16/17 08:21 AM

iagree Cool car I bet.
Posted By: qwkmopardan

Re: 512 BBM-- How much power??? - 12/16/17 07:04 PM

I have pictures but since photobucket wants a million dollars to use there site now, I don't know how to get pictures on here.
Posted By: Anonymous

Re: 512 BBM-- How much power??? - 12/16/17 09:59 PM

Go to Imgur, very easy.
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