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GPM 03-18-2018 09:55 PM

I would think you would be close enough at 9.9, but that's just me.

Baja Rooster 03-18-2018 11:15 PM

2 Attachment(s)
I found some -6 of the same design and those seem to land me right where I can fine tune chamber volume with head gaskets.

GPM 03-19-2018 02:15 PM

There you go, good luck with your build !!

getrdunn 03-19-2018 04:25 PM

I get where your at now just most piston manufacturers consider domes a +cc so in original post I assumed dish. No biggy. What is the part number on your heads? #60479? Also you are you leaving heads untouched. A little work on those would make your engine happy and would increase CC's if you did some chamber work and a little unshrouding. GM oval ports flow similar with not a lot of effort with 2.19/1.88 valves. Regardless your gonna have a nice reliable build.

MILD THUNDER 03-19-2018 05:40 PM

IMO, going from a 224/234 110 LSA camshaft, to a 226/236 112 LSA cam, is a waste of time. 2 degrees of duration, and 2 deg of LSA , arent going to change much.

I would much rather have went to at LEAST the crane 741 cam, preferably even a tad larger being that you are going to be 10:1 compression. I think the 731, with that much compression, you're gonna have to run 93, or be very close on your tune up. The HP500 cam, is slightly smaller than the 731 and ZZ502, but also was like 8.75:1 static. Id guess with either of those cams, she will be done around 5200RPM as far as making HP. At that point, you might consider keeping the ZZ502 dual plane intake, the Victor JR might not even begin to outperform it until close that area...I'd really lean towards the 741 cam in this build myself.

getrdunn 03-19-2018 06:42 PM

Some good points.

Baja Rooster 03-19-2018 08:48 PM

The serial number on the head is 19510 and 6045. I bought this engine off of Vintage Chromoly years ago and he had the heads massaged a bit. When I had them rebuilt last year the machinist said that they looked pretty good.

When I started this project I didn’t plan on changing much and got the 731 cam to use with the flat tops that are likely about 9.3:1 or so but a lot has changed. At this point I’ll probably grab a Comp cams EFI525 clone or 741 if one pops up.

MILD THUNDER 03-19-2018 09:13 PM

I'd also be very careful what piston you choose with those heads bajarooster. That head has spark plugs that are closer to the center of the bore, which some dome pistons can hit.

MILD THUNDER 03-19-2018 10:01 PM

..


Tech Note: The Spark plug is closer to center of bore, for use with flat top or low dome pistons and will interfere with high-dome pistons for open chamber heads. If a high compression domed piston is to be used, purchase a piston designed for use with this Edelbrock cylinder head.

Tech Tip: To gain more spark plug clearance, Edelbrock recommends using Champion RC Series plugs such as the RC12YC. They are 0.230'' shorter than a conventional spark plug and have a 5/8'' hex for easier access.

getrdunn 03-19-2018 10:25 PM


Originally Posted by MILD THUNDER (Post 4616924)
I'd also be very careful what piston you choose with those heads bajarooster. That head has spark plugs that are closer to the center of the bore, which some dome pistons can hit.


i did a little reading on that also.


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