Street 572 wedge build

I'm gathering parts for my next engine build. It's gonna go to my 66 Dart street car, t56 magnum and S60 with 3.73 gears. 99% street driven.

I already have BMP aluminum block and Molnar 4.500 crank + 7.100 on the way to Finland and now I would like to get some opinions about what compression and cam I should go.

I will get my pistons from Diamond and compression options would be: 10.0 / 10.2 / 10.6 / 10.95 or 11.35

Fuel is going to be European 98 octane which is 93 octane in the US I think?

I want to use mechanical flat tappet cam because lower valve spring pressure thus easier for valvetrain on street use. I know big mechanical roller would make the most HP but this build is more of durability than maximum horsepower.

I already have heads and intake from my previous 535 cu.in engine which are going to my new engine also. Super victor 4500 flange intake and ported MW Victor heads. That 535 made 750hp @6100rpm and 685 ft.lbs @5300rpm with 272/284 @0.050 0.660/0.630 mechanical roller cam. We pulled it only to 6200rpm on the dyno and hp curve was still climbing @6100rpm so I don't know if it would have made little more even, but didn't want to push it because it had stock block.. So heads are good for 572 too I think, my head guy says they are made to peak at 6500rpm in 535 cu.in engine, of course it depends what cam is used..



I'd be happy with 700ish hp and so that engine wouldn´t be completely dead at upper rpm range..

So if you guys could give me your opinions about compression and cam I'd be very happy.

I wouldn't go any higher than 10:1 on the compression and if I was building it here in the states I'd actually stay with something in the 9.5 to 10.0 range for compression. That is with big dish piston and tight quench. Cam choice all depends on how you are really going to drive the car. With a manual transmission and a T56 transmission I'd stay really small with the cam. You don't want to be cruising down the freeway at 1800 rpm and be blowing the intake mixture out the exhaust because you have a ton of overlap. With a double overdrive transmission you need a really small cam or else you'll just pour gas out the tail pipes on the freeway.

Last engine was 11.5:1 and my new one is `12:1 on pump gas. Cam shaft will play a big roll in how much compression you will want.

If you are going to cruise in 6th gear then you'll have either a 1.87 rear ratio, or a 2.35 rear gear. So that puts you at roughly 2000 rpm for 80 mph depending on tire size. Dwayne is the guy to talk to about the cam but I'm thinking you need to stay in the 250 @ 050 range if you want to drive on the freeway at less than 2000 rpm. I'm not sure what the port velocity is going to be like at 2000 rpm with the MW Victor heads even with 572 cubes to feed. That engine might not like double overdrive, you'll just have to try it and see.

The Chevy 572/620 crate engine might be something to take a look at. Chevy went with 9.6 compression and the cam is 254/264 hyd roller. I haven't tested one of those engines but I assume it would work with an OD transmission since it is designed as a street rod type engine rather than a race engine. Chevy sells the 572/620 in their "connect and cruise" package with a T56 double overdrive transmission. Maybe jump on a Chevy board and see if you can find some reviews of that camshaft with the double overdrive in a car with your weight, tire size and rear gear.

I worked with Dwayne on my mild 541 build. The application is decidedly different since it is a very heavy car with an automatic and 3.23 rear gear. We planned for the 518 OD transmission. The cam is a 235/241 hydraulic roller made to play nicely with the power brakes and still make silly amounts of torque through the mid range.

I've got the engine together now and trying to work out the scheduling to get it on the dyno.

With an aluminum block and aluminum heads you can get away with a LOT of compression on pump gas. The block will which away heat so quickly NONE of those ratios you listed would concern me as far as to much for the octane of the fuel goes. If it were me I would be shooting for the upper end of that scale if not higher. It is very difficult to build cylinder pressure in an aluminum block. Also if it were me I would look at a roller cam, solid preferable but hydraulic at least, they done have to be big to make power and not worry about lifter life.

I'm really interested in this thread.
Andy F and Al Alguire are both vastly more knowlegible than I am. It seems there is a bit of a difference in opinion on how far
one can go with this particular engine build, for it's use.
I am not fanning any flames here, or at least not trying to.
Interested in learning.

Not much experiance on a deal like this, but a short duration cam and some form of boost might be very interesting!

Here is an older archived build for comparison, click here for link

I remember that thread. A little over 10 years ago. Be interesting to get an update on that engine and car.

Those early A bodies have virtually no room( engine bay) for headers ( even the TTI ones suck to install ) on a small block. Or much else
Can’t imagine working on one with a big block, no room for nothing unless you chop up the car.

edited


I thought he posted an update somewhere, but all I can find is that it ran 10.9’s @ 124 and was still being sorted out. He hasn’t been on the Charger board in a year and hasn’t posted in 2 years

On your deal, I'm building a very similar race 572 with B1 heads now, I would shoot for 10.6 to 1 compression and tuned it for max power and tire spinning torque with that fuel
Have fun, my new race car is a 1965 Dart 270 that I'm going to run the 1966 front end on it for better aerodynamics
My current plans are using a after market race Powerglide with 4.30 gears in the Dana 60 and the biggest tire I can run legally, probably a16x34x16 bias ply slick on 16 inch wide bead locks