I am rebuilding my old trusty 496 for my 72. The old engine is a 454 2 bolt .060 over with 2.06 and 1.72 stock valve size "049" lg. oval port heads with a pocket port, ran a CC 294S cam, and old ED. Perf. intake, with a 750 Edel. carb. With a 3.08 12 bolt Posi and a M-21 it ran high 12.30's and a lot more 12.40's on 28x10x15 slicks. ***My new combo I am going to a TH-400, 3.55 gears, depending on cam choice a 2400 to 3000 stall converter, a Holley 850 DP, like to stick with a good dual plane intake, and because of cost would like to stick with a new solid flat tappet cam, I got new CC magnum roller rockers. ****NEW USED heads I bought from a pal are the CANFIELD aluminum 310 cc 119 cc chambers rect. port, he used them for two years with a roller set up and now bought some bigger Brodix's for bigger motor. I will be putting all new matching valve train components in the heads alomg with new Manley valves.**** My engine builder sonic tested the block and said it is safe to go to .100 over but we feel it would be better to get some custom pistons by Ross or SRP in .070 or .080 over. He would like me to use a roller camshaft, I will consider that, If the extra price is worth it. ***This car is 80% street and 20% strip just for fun. Do you guys think these heads will make a big diffrence? Any cam and converter choices? I feel I could not pass up these used heads at the price I paid for them. Plus I will lose some weight on the front end. What about header size? I run 1/3/4" primaries now. Thanks! graemlins/beers.gif

I forgot compression ratio on old motor was 10.28. New motor will be in 10.5 to 10.75 compression ratio. graemlins/beers.gif

Tom (mc71454) uses those heads on his 540 that runs 10.70's with 3.42 gears..I don't think you'll be in the 12's anymore ;) :D

Thanks I hope so. I was looking to get into those new Brodix RaceRite oval ports, but I got these Canfields for only $600 bare. Even though they are two years old I felt the price was to good to pass up, even that they are quite bigger (runner size). I am going to check out Lunati's new site and see the solid flat tappet cams. The engine builder really wants me to use a nice street roller, nothing crazy he said, we will see. graemlins/beers.gif

I honestly wish I had waited and bought the 310 Canfields for my 496 instead of the cast-iron Merlin ovals.. Just b/c of weight, if for no other reason.. They weren't out way back then when I got the Merlins..

AND I like the 100 cc chamber size of E-brock's 290 heads for lower CR. motor, flat-top piston use, but not the roval port shapes..

I think all you will need is just an E-brock, RPM and you will be set b/c the old 294S should go better with more CR. OR maybe a good old Strip Dom. single plane to kill a little low end and add a schosh more to the high end sorta thing like I went with..

Try it first...

THEN please check with Harold at Lunati's for a more modern grind like he CAN recommend!!

pdq67

Just checked out Lunati's new site. I was thinking of going to this solid roller, it is the smallest one they have. Looks like an old Ultradyne grind. Part # 502A1LUN grind # UR-34-UR32 Advertised duration is 278 Int. 290 Exh. at .050 duration is 244 Int. 255 EXH. .630 lift Int. and .630 Exh. 112 lobe seperation. Says great power from 2000 rpm to 6000 rpm with 10.5 compression should work nice with the automatic. graemlins/beers.gif

On that big an engine the factory oval really isn't big enough for any really serious work. Your head change should make quite a bit of difference.