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What size intake valves and which heads were on those?!!!! Nice numbers.
This is a head I developed when I was at Straub and something I was wanting to develop for a long time. These two customers (with the 427's) provided the opportunity. This is what I called my "little big port" or "game changer" which is a small 290cc rectangle port in the conventional location with a small chamber made to work on 427's and 454's. I started the idea with a 2.19 valve which really would be better for these combinations but for "marketing" I was talked into a 2.25 valve. They flow >370 with the 2.25 valve with really good low and mid lift numbers. They are done on an AFR porter casting.
I did a post on it a while back:
 

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What is the point of cutting the deck down? The CH as is doesnt seem a detriment to me.
It's not about the compression height, it's about taking advantage of the rpm potential of the big bore/short stroke. Shorter deck makes for shorter pushrods and shorter intake runners...both pretty much a necessity if you want to run in the upper rpm range and I'm talking about in the 9K+ range. It's pretty common, really, for anything turning that sort of rpm.
 

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What size intake valves and which heads were on those?!!!! Nice numbers.
We did a few like that with various results.
265377


  • 1969 052 block, 100 over
  • Eagle 4.00 stroke so 475 inches
  • Eagle +.250 rods
  • Je pistons
  • .904 Comp roller lifters
  • .715 .258 on .114 Comp cam
  • trends pushrods
  • 1969 074 heads ported with 2.25/1.94 valves
  • Comp 1.7 roller rockers
  • 1969 198 dual plane intake ported

785Hp from 6700to 7200. 705Tq @ 5100
 

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So, 0.18 shorter pushrods and intake runners are the difference between good performance and great?
I wouldn't say that. Just lessening the issues for higher RPM. Was also done yrs ago for a weight saving in an NA engine as well.

This one of mine is just under 9.600 DH. Will double check CH on piston, but 3.75 stroke and still ran a 6.660 al rod. Comp was right around 1". Numbers come in at 4.535 but need to add for al rod stretch, so has me believing 9.560 area for DH.

NOTE upper water pump holes.

265385
 

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Long Live The King
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I wouldn't say that. Just lessening the issues for higher RPM. Was also done yrs ago for a weight saving in an NA engine as well.
You wouldn’t say it and neither did Scott. As you are aware It’s about the optimization of the combination. if you’re building something to run and live at 9,000 every little bit helps and eliminating the push rod flex and weight goes a very long way.
kind of Engine Building 101.

it could be the difference between “running good” and then running better ( isn’t that always the goal) or “running good” and one step closer to running perfect. Those shortened lighter weight push rods just might be the answer to a much better/smoother operating valvetrain.

PS: Several little things added together = a large step.
 

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Diamond quoted us 21 days on 2 pistons we needed replaced and it took over 3 months to actually get them.



If you were going to push the RPM then I'd tend to agree on shortening the deck as much as possible, but with an intended 7500rpm max it'll be fine working with it as-is. - I'm all for working with stuff I have laying around, but for what you're wanting out of it a nice 4" or 4.250" crank would make more power at that relatively low rpm peak.
 

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Discussion Starter · #49 ·
Diamond quoted us 21 days on 2 pistons we needed replaced and it took over 3 months to actually get them.



If you were going to push the RPM then I'd tend to agree on shortening the deck as much as possible, but with an intended 7500rpm max it'll be fine working with it as-is. - I'm all for working with stuff I have laying around, but for what you're wanting out of it a nice 4" or 4.250" crank would make more power at that relatively low rpm peak.
I have all the stuff and it's back to school shopping for 2 girls so new crank is out of the question. It was supposed to be a 532 but my old cola crank didn't mag. I've looked for a good used crank online. Can't afford a good new one.
 

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Long Live The King
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I have all the stuff and it's back to school shopping for 2 girls so new crank is out of the question. It was supposed to be a 532 but my old cola crank didn't mag. I've looked for a good used crank online. Can't afford a good new one.
Was this from the fire ?
 
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Discussion Starter · #51 ·
Was this from the fire ?
It was from the fire. I think it's ok and just needs to be turned. It's currently at a machine shop in Arizona along with my dart heads. My buddy dropped the crank and heads off and called me and said the heads are good but need guides and seats obviously. But said the crank was bad. I'm going to take it to marine crankshaft and have them tell me. So I have the Bryant left.
 

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Discussion Starter · #52 ·
Was this from the fire ?
Just got the block back from another machine shop lmao. It's good it had to be bored to 4.60 from 4.56 and the decks got taken down to 9.78. Only had 20 passes. Anyway my machine shop woes are done now. I won't say that I have enjoyed working with any machine shop lately. It's funny I pay money and most of them act like they are doing me a favor to get done on time or answer the phone. I will be assembling this one myself with my buddy Spike over my shoulder.
 

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Long Live The King
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It was from the fire. I think it's ok and just needs to be turned. It's currently at a machine shop in Arizona along with my dart heads. My buddy dropped the crank and heads off and called me and said the heads are good but need guides and seats obviously. But said the crank was bad. I'm going to take it to marine crankshaft and have them tell me. So I have the Bryant left.
I was going to suggest Marine Crankshaft. I’ve heard some good things about them.
 

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Discussion Starter · #58 ·
You are confused.
I was going to suggest Marine Crankshaft. I’ve heard some good things about them.
They come highly recommended. Ya know I was sitting here laughing about building a small 500 cubic inch big block. Growing up in the 80's a 500 cubic inch big block was made of unobtanium for mere mortals. 🤣 I'm going to be completely happy with this thing. Couple years down the road I will pull it and change it up to a 565.
 

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I appreciate and value your opinion, but in this application color me skeptical.....
Allow me to shed some light on this for you:

Post: 14
If you're going to spin any kind of rpm, your limit (@ 500ci) is going to be the heads and intake. I was thinking a little more outside the box with the short stroke/short deck combination and a LOT of rpm but your induction won't support it. I would target your build around making peak power somewhere in the low to middle 7k rpm range. I agree with Nick. ^
805 350 1159
" I was thinking ...." is PAST TENSE ...

" I agree with Nick" should be self explanatory (assuming you read Nick's post #7 )

Post 43
It's not about the compression height, it's about taking advantage of the rpm potential of the big bore/short stroke. Shorter deck makes for shorter pushrods and shorter intake runners...both pretty much a necessity if you want to run in the upper rpm range and I'm talking about in the 9K+ range. It's pretty common, really, for anything turning that sort of rpm.
" If you want to run ..." is referring to his (Scott's) first blush thought on the application he first had in mind (see post 14) , before he agreed with Nick's assessment (post 7) and stated " I would target your build around making peak power somewhere in the low to middle 7k rpm range."

The Low to middle 7K rpm range is a different application than what Scott originally suggested cutting the deck height down on. It's now reasonable to conclude that Scott would not suggest cutting the deck down for the 7k application as it's not necessary for this application and the intended rpm range. He agreed with Nick's "RECIPE" when he stated in post #10:
lol...or that^.
I hope that sheds some light on this for you.

You're welcome.
 
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