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Quote:

Originally Posted by ThisIsLivin (Post 4592355)

Just caught this thread. I have a 524 similar to what you are looking to build. It's a 4.565 bore with a 4" stroke, 6.385 Eagle H-beam rods, AFR 305 Rectangular heads with CNC chambers and bowls, Brodix HV2000 intake that has been ported with the heads. Custom Holley 950 cfm 4150, custom hydraulic roller cam with .611/.623 lift 242/252 @.050, 10.1:1 compression, Crower stainless rockers with a stud girdle. MSD 6M ignition and Lightning wet headers. It sounds awesome, a little too, I had to put Gibson mufflers on it to keep from getting tickets. First time I started it after the rebuild in the marina, it sounded like thunder. I never had it dyno'd but it runs better than it sounds. I've had my boat to 90 with 4 people and a full tank of gas, I can only go half throttle getting on plane or the prop blows out. Acceleration from 45 is absolutely amazing. Big bore short stroke engines are very efficient and love to rev quickly.

you did not post hp or torque numbers,was this engine ever on a dyno?it sounds like a good combination.

89/90 octane ethanol free is what is available where we fuel at, should I stay around 9:1 with the srp flat tops or would the srp small domes be better at 10:1 ?

I run a small dome in my 548 at 10:1 and I run normal 91 octane Costco gas. No issues so far and no detonation.

Quote:

Originally Posted by TylerBurich (Post 4592466)

89/90 octane ethanol free is what is available where we fuel at, should I stay around 9:1 with the srp flat tops or would the srp small domes be better at 10:1 ?

Are you going to be running aluminum or cast iron heads.

Just saw aluminum for your heads.
Are they 119cc chambers.
If so I would go with the 10-1 and put a thicker head gasket on it that would probibly put you at high 9s or 10 even.Which with a correct tune and timing should be good to go with the aluminum heads.

Cast iron heads and you would be pushing it.

Quote:

Originally Posted by Warship2k15 (Post 4592471)

Yes, 119 Chambers. That could change if I have any work done on the chambers when the heads are redone. I'll make sure to get the piston height and quench right on the money if I go with the small domes.

Quote:

Originally Posted by Tahoe540 (Post 4592467)

I run a small dome in my 548 at 10:1 and I run normal 91 octane Costco gas. No issues so far and no detonation.

You run at real high elevation though, right ? You are probably super safe at that compression up there. You can run a bunch more on the same gas than those of us near sea level.

Crane Hydraulic Roller with 234/242 and 112 LSA looks good as well as the 741. Does anyone have any really good software they can plug that combo into?

Slight side track:

I looked up Tahoe's Elevation (6,225 ft) and couldn't help notice this fact:

Depth: 1,645 ft WOW !

Damn I get a little queezy when I pass over a 180ft depth spot on my lake.

You guys ever worry about a dinosaur or something coming up to the surface. :lolhit: :bunnydance:

Quote:

Originally Posted by SB (Post 4593088)

Slight side track:

I looked up Tahoe's Elevation (6,225 ft) and couldn't help notice this fact:

Depth: 1,645 ft WOW !

Damn I get a little queezy when I pass over 180ft depth on my lake.

You guys ever worry about a dinosaur or something coming up to the surface. :lolhit: :bunnydance:

I felt the same way on Lake Macdonald in Montana... 10 miles long 700' deep!