vintage chromoly

iTrader: (3)

800 HP and around 800 Ft lbs. Of torque from the research I've done. Spinning 7500 to 7800 RPM.

sutphen 30

thank you
700hp is gonna be a tall order for a 517ci engine at 6000rpm.

mike tkach

iTrader: (3)

a 4.560 bore with a 3.910 stroke would be 510.84 cu in.i thought i read that the bore was going to be 4.560 and the stroke was 3.910.with 10 to 1 compression ratio spinning a max of 6000 rpm it should be a good running engine but 700 hp might be a little high.my guess is around 650.650 in the 24 ft boat with a bravo drive should be a rocket ship and a blast to drive.

vintage chromoly

iTrader: (3)

The crank measured 3.920 and the bore will be 4.560 so that should be a 512.

When I started the thread I thought I had a 4 inch crank with a 4.530 bore. It ended up being a 3.920 crank and a 4.540 bore to make a class legal 509.

The dyno will tell the tale as far as where we end up power wise.
As mike said. In a 24-7 hull, it should prove to be plenty fun.

Thanks for the interest guys.
I'll keep updating as we go.

Have a great Christmas all,
Rob

rmbuilder

S-30/Mike,
All good observations regarding the specific output of this engine. In the initial conversations concerning the transformation of this engine package, the target of 700 hp was based upon a semi-compression engine turning in the neighborhood of 6600 RPM. After a number of exchanges, all the practical aspects were assessed, and the project moved towards a more performance orientated recreational engine rather than a competition package.

With the move to 9.5:1 compression ratio and max wide open throttle target of 6000 RPM, the number 650 to 670 is much more realistic in this application. The subsequent reduction in duration (we have changed the cam specs four time so far) will build better acceleration in the midsection and yet still carry RPM beyond peak. The 55 mm core with its decreased deflection and reduced pressure angle will make for a very stable valve train.

My experience in racing a 510 engine making north of 700 hp is; they are a blast to race, but not a recreational engine you want to live with on a daily basis. The service life of your parts go down and your maintenance cycle goes up, not to mention the lack of maneuverability in tight spaces gets real old real quick. This is a well thought out project and will certainly make its marks for both performance and durability.


Merry Christmas and Happy Hanukkah. We wish you all a healthy, happy, and prosperous new year.

Bob

mike tkach

iTrader: (3)

bob,no doubt that this build will reach the intended hp goal,i really like the idea of the 55 mm cam.650 in a 24-7 should be a rocket.merry christmas,happy holidays to all.

vintage chromoly

iTrader: (3)

Thanks bob.
We will be ordering the cam and associated hardware shortly.
I appreciate your patience and help on this as we want to get this right.

Have a great Christmas all.

hogie roll

I doubt that's how much torque they made, just based on hp and rpm.

endeavour32

iTrader: (4)

So anything new with your project? Did you ever get the flow numbers for your heads?

vintage chromoly

iTrader: (3)

Ordered the Pistons last week. Went with CP bullet Pistons. One of the cool things about them is you can order them with .150, .180 or .200 walled pins. I went with the .200 wall pins.

My friend is dropping off the block, crank, pistons and rods at victory engines sometime later this week. We will be resizing the rods, boring the block to 4.560, sizing everything up to order bearings and we're having the bronze lifter bored bored and honed for larger .903 lifters. Oddly enough, they were .842 lifters.

Going to order the cam, lifters, springs and hardware from bob shortly. Going with morel needle bearing lifters and the isky tool room springs that bob recommended.

Also, got the barnes dry sump pump all cleaned up and ready to re-assemble. Had to switch the location of one of the mounting plates to align the pulleys.