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#1
05-14-2021, 03:28 PM
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Another 428 thread
So to make a long story short, I’ve got a 68 428 .030 and have the same L2257F sealed power pistons in it like “Racerboys” post. 4 reliefs and a 2 1/4” dish.... got a set of #13s that measure 75-76cc and flow about 240cfm. At about 9.7cr it should support a roller 230 to 240 at .050, right? 3.70 9” and a TKO600.
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 "NSDQ"
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#2
05-14-2021, 04:59 PM
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Using common specs like 12 cc total for the dish and valve notches, 9.4 CCs for a head gasket , ,019” deck , 1.5 cc ring land volume and 75 cc heads I come up with a compression of 9.66 which should be just fine with a iron head and that Cam.
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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
05-14-2021, 05:11 PM
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Butler gaskets are 46 thou.All I use now.Tom
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#4
05-14-2021, 08:40 PM
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Quote:
Comp QXI 13448 283 @ .006 231 @ .050 152 @ .200 .389 lobe lift |
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#5
05-15-2021, 09:08 AM
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I kind of remember this engine. Was it originally rebuilt by Spaniels in Lincoln? Did you take it apart and look over what all was done to the short block and heads?
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#6
05-15-2021, 09:35 AM
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Heads were done by him, and short block was done by a guy named Andrews. He had done the machine work on my 400 I have in there now. I have just pulled a head to confirm the pistons used. May just pull one rod and check clearances.
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"NSDQ"
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#7
05-20-2021, 02:00 PM
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So, I have two sets of #13 heads to consider for this 428. One have been ported, no flow sheets, and the other has only a valve job and no visible grinding in the ports. Found a guy local to me, to flow one cylinder on each just to know if the porter did well, or ruined the heads. The ported heads seem like the intake valve is sunk in a bit, so who knows what it will turn up. I will post both the stock and the ported flow when I get them back. Should have them back in a week or two.
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"NSDQ"
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#8
05-27-2021, 10:39 AM
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Quote:
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1971 Pontiac Trans Am Cameo White 1968 Firebird 400 coupe, Verdoro Green w/black vinyl top 1968 Firebird 400 convertible, Verdoro Green w/black top 1970 Buick Skylark Custom convertible(driver) Fire Red 1972 Buick GS 455 Stage 1 Royal Blue |
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#9
05-27-2021, 11:11 AM
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No, not as of yet. With my work schedule it will be a couple weeks before I can get back there and pick them up.
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"NSDQ"
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