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They have a 502 for sale near by but not very sure about the set up, so what do ya'll think. It's going in my 65 Chevelle if I get it. Thanks for the help, 502's are new to me. Heres the ad:

Gen 6 502 BBC with 502hp/502cid hyd. roller cam. Ported "781" oval port heads with hardened exhuast seats, 2.19/1.88 SS valves and three angle valve job. New Comp Cams valve springs, ARP rocker arm studs, and Comp Cams Pro Magnum roller rockers. This is a 4 bolt main block with factory windage tray, Forged Steel GM crank, 7/16" bolt GM rods with ARP bolts, Std 502 forged dome pistons and moly rings. Topping off engine is an Edelbrock Performer RPM intake, 795 cfm Qjet carb and HEI dist., comp. 9.6 to 1, cam specs ZZ502 cam. The motor should make around 525 H/P and 590 TQ. The engine was started but never finished project so zero miles. Asking price 4K.

Does the comp. sound right? I thought it would be less.
Is it ok to use 781 heads on a gen 6 502?
Price, I thank is ok but will try to get it for less.

Little shy about buying a engine form someone I don't know. I have been burned by someone in the past. They painted the thing and called it newly rebuilt on top of having several thing done wrong to it on the inside causing a failure. So for you that know 502's if something does not seem right let me know. They will be others.
Ron
 

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They have a 502 for sale near by but not very sure about the set up, so what do ya'll think. It's going in my 65 Chevelle if I get it. Thanks for the help, 502's are new to me. Heres the ad:

Gen 6 502 BBC with 502hp/502cid hyd. roller cam. Ported "781" oval port heads with hardened exhuast seats, 2.19/1.88 SS valves and three angle valve job. New Comp Cams valve springs, ARP rocker arm studs, and Comp Cams Pro Magnum roller rockers. This is a 4 bolt main block with factory windage tray, Forged Steel GM crank, 7/16" bolt GM rods with ARP bolts, Std 502 forged dome pistons and moly rings. Topping off engine is an Edelbrock Performer RPM intake, 795 cfm Qjet carb and HEI dist., comp. 9.6 to 1, cam specs ZZ502 cam. The motor should make around 525 H/P and 590 TQ. The engine was started but never finished project so zero miles. Asking price 4K.

Does the comp. sound right? I thought it would be less.
Is it ok to use 781 heads on a gen 6 502?
Price, I thank is ok but will try to get it for less.

Little shy about buying a engine form someone I don't know. I have been burned by someone in the past. They painted the thing and called it newly rebuilt on top of having several thing done wrong to it on the inside causing a failure. So for you that know 502's if something does not seem right let me know. They will be others.
Ron

I PAID $4500 FOR A SHORT BLOCK. That being said. I think that is a hell of a deal.
I don't think the 781's came on there from GM. I would get the numbers off the block to verify that it is indeed a 502. if it is pick it up and have some fun.
 

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Sounds like a good deal to me. You can use a 781 head on a Gen VI , but you have to use the newer style head gaskets. The 502's come with a truck style oil pan, if it hasn't been already changed to a car pan.

Dave
 

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502 block should have 8.2 raise on the side of the block . that's good price, am selling the long block alone for $2500 that need rebuild but my have Square port heads
 

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They have a 502 for sale near by but not very sure about the set up, so what do ya'll think. It's going in my 65 Chevelle if I get it. Thanks for the help, 502's are new to me. Heres the ad:

Gen 6 502 BBC with 502hp/502cid hyd. roller cam. Ported "781" oval port heads with hardened exhuast seats, 2.19/1.88 SS valves and three angle valve job. New Comp Cams valve springs, ARP rocker arm studs, and Comp Cams Pro Magnum roller rockers. This is a 4 bolt main block with factory windage tray, Forged Steel GM crank, 7/16" bolt GM rods with ARP bolts, Std 502 forged dome pistons and moly rings. Topping off engine is an Edelbrock Performer RPM intake, 795 cfm Qjet carb and HEI dist., comp. 9.6 to 1, cam specs ZZ502 cam. The motor should make around 525 H/P and 590 TQ. The engine was started but never finished project so zero miles. Asking price 4K.

Does the comp. sound right? I thought it would be less.
Is it ok to use 781 heads on a gen 6 502?
Price, I thank is ok but will try to get it for less.

Little shy about buying a engine form someone I don't know. I have been burned by someone in the past. They painted the thing and called it newly rebuilt on top of having several thing done wrong to it on the inside causing a failure. So for you that know 502's if something does not seem right let me know. They will be others.
Ron
The zz502 arrives at 9.6/1 with the 110 cc chamber.The 781 chamber is larger by who knows.The oem heads are all over the place.Even with a 1/2 point static cr differential..your butt o/meter will not pick it up.The zz502 is underated at 502 hp/565 ft lbs.More like 535 hp/580 ft lbs.This is with Eddys tin heads with 2.250 intake valves.You did mention the 781,s have been ported with a competition grind..this is good.They might just make as much or more power than the eddys.FWIW..we woke up our zz502 with more initial timing than recommended and swapping out the 850 vac secondary for a hardcore 870 double pump.IMHO only..the zz502 is seriously under cammed.This is a weeny cam over 502 cid.Better suited for marine application and not hot street usage.The quadrajet would make for a nice daily driver with its tiny primarys and ability to move a/f when the secondarys roll in.I do believe though..that 502 cid can gobble up more cfm than 795.
 

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The motor would be 8.75-1, if the heads are at 119cc chambers, the 781/049 are known to be as big as 123cc. They should have used the 71-72 heads with the 113cc chambers would have help alot making comp ratio more like 9.25-9.5.
 
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