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#1
08-10-2014, 06:21 PM
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Edelbrock head question
on a 462 engine with a with flat top pistons, running a comp 274h cam would 72cc heads produce too much compession for pump 93 fuel?
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70orbitorange |
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#2
08-10-2014, 07:53 PM
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I would say you would be right on the edge even if the pistons have 4 valve notches with that cams cranking compression you will have.
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Wernher Von Braun warned before his retirement from NASA back in 1972, that the next world war would be against the ETs! And he was not talking about 1/8 or 1/4 mile ETs! 1) 1940s 100% silver 4 cup tea server set. Two dry rotted 14 x 10 Micky Thompson slicks. 1) un-mailed in gift coupon from a 1972 box of corn flakes. Two pairs of brown leather flip flops, never seen more then 2 mph. Education is what your left with once you forget things! |
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#3
08-10-2014, 08:13 PM
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that's what I thought too.
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70orbitorange |
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#4
08-10-2014, 11:47 PM
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Yes, very poor cam choice for a 455 engine with E-heads and that much compression, it will not be a pump gas friendly engine.....Cliff
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If you can read this, thank a teacher. If you can read this in English, thank a Veteran! https://cliffshighperformance.com/ 73 Ventura, SOLD 455, 3740lbs, 11.30's at 120mph, 1977 Pontiac Q-jet, HO intake, HEI, 10" converter, 3.42 gears, DOT's, 7.20's at 96mph and still WAY under the roll bar rule. Best ET to date 7.18 at 97MPH (1/8th mile), |
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#5
08-11-2014, 08:25 AM
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It would be a toss up between not using that 274 cam that you have and getting a tad bigger one, or have a shop grind in 4 to 6 more CCs into the E heads chamber on the deep side across from the intake valves.
The cam or the chamber rework would be about the same bucks with a shop that knows what it's doing if you can not your self!
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Wernher Von Braun warned before his retirement from NASA back in 1972, that the next world war would be against the ETs! And he was not talking about 1/8 or 1/4 mile ETs! 1) 1940s 100% silver 4 cup tea server set. Two dry rotted 14 x 10 Micky Thompson slicks. 1) un-mailed in gift coupon from a 1972 box of corn flakes. Two pairs of brown leather flip flops, never seen more then 2 mph. Education is what your left with once you forget things! |
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#6
08-11-2014, 04:04 PM
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Most of the 72cc E heads I've checked come in around 75cc.
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Skip Fix 1978 Trans Am original owner 10.99 @ 124 pump gas 455 E heads, NO Bird ever! 1981 Black SE Trans Am stockish 6X 400ci, turbo 301 on a stand 1965 GTO 4 barrel 3 speed project 2004 GTO Pulse Red stock motor computer tune [email protected] 1964 Impala SS 409/470ci 600 HP stroker project 1979 Camaro IAII Edelbrock head 500" 695 HP 10.33@132 3595lbs 1964 Corvette Coupe 327 4 speed |
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#7
08-11-2014, 07:26 PM
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A small amount can be gained too, by "unshrouding" the intake valve to the gasket. We have a dedicated "Mira" cutter set to the size, but most decent shops have one. A radius of at least .125" should be used (all the way down to the seat). You'll gain another 2-3 CCs, and maybe 5 CFM. Worth it.
Agreed, XE274H is not a good choice. With those heads, you really need at least [email protected] to make them "work". XE284H fits in the parametric range, but may also be "too fast" for the compression. If you must stay with the flat tappet, I'd prefer something in a symmetric lobe solid. 236/[email protected], maybe .550-.570 lift would do the trick. We get "custom" grinds all the time. No big deal. FWIW Jim |
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