14:1 /454 Gen 3 Gemi making 700 hp naturally aspirated

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Wild one

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dhay13

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Never built a Hemi but built plenty of V8 Chevys. My 454 was pushing 650HP n/a back in 1993-ish. 454 .060 over, 12.5:1. stock oval port heads, .685/.692 lift Lunati roller with 280* duration at .050 lift. Can't remember the intake but think it was a Victor Jr. 850cfm Holley double pumper. 2.25" ****** super comp headers. 3800-7400 RPM. Loved it...lol. Had this in my '69 Chevelle with a 6pt roll bar and a 9" KTRE rear end with 4.56's and Moser axles with an 8" ATI convertor in a THM400.
The last one I built was a 393 SBC. De-stroked 406. 6" Oliver rods. 10.7:1 Ross pistons. AFR aluminum heads. Sommers Bros gear drove, 4 bolt splayed caps. Hank the Crank forged crank. Victor Jr intake. 750cfm double pumper. Comp Cams roller. Can't remember the specs but it was about a .650 lift. RPM range was 3500-7000. Dynoe'd at 552HP at 6500 RPM on pump gas. Had that in my '57 Chevy with 6pt roll bar and mini tubs with 4.10's with a 10" TCI convertor with a THM350
 
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Wild one

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Never built a Hemi but built plenty of V8 Chevys. My 454 was pushing 650HP n/a back in 1993-ish. 454 .060 over, 12.5:1. stock oval port heads, .685/.692 lift Lunati roller with 280* duration at .050 lift. Can't remember the intake but think it was a Victor Jr. 850cfm Holley double pumper. 2.25" ****** super comp headers. 3800-7400 RPM. Loved it...lol. Had this in my '69 Chevelle with a 6pt roll bar and a 9" KTRE rear end with 4.56's and Moser axles with an 8" ATI convertor in a THM400.
The last one I built was a 393 SBC. De-stroked 406. 6" Oliver rods. 10.7:1 Ross pistons. AFR aluminum heads. Sommers Bros gear drove, 4 bolt splayed caps. Hank the Crank forged crank. Victor Jr intake. 750cfm double pumper. Comp Cams roller. Can't remember the specs but it was about a .650 lift. RPM range was 3500-7000. Dynoe'd at 552HP at 6500 RPM on pump gas. Had that in my '57 Chevy with 6pt roll bar and mini tubs with 4.10's with a 10" TCI convertor with a THM350
We could only dream of having heads that flowed as good as the newer 6.4 heads flow
 
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Wild one

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Don't know, but the Hemis of old flowed pretty good. Our AA Fueler was doing 2500 HP back then in the 70's with no computers.
There were exceptions to the rule,if you had enough money,lol. Not many guys ran a top fuel engine on the street though :Big Laugh: The top fuel heads of yesteryear are down a bit in comparision to what's available today.
These days it's not uncommon to make in excess of 1100 rwhp from 400 cubes on a daily driven street car,in the 70's you weren't making that power and daily driving it on the street,let alone from 400 cubes,lol
 

04fxdwgi

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There were exceptions to the rule,if you had enough money,lol. Not many guys ran a top fuel engine on the street though :Big Laugh: The top fuel heads of yesteryear are down a bit in comparision to what's available today.
These days it's not uncommon to make in excess of 1100 rwhp from 400 cubes on a daily driven street car,in the 70's you weren't making that power and daily driving it on the street,let alone from 400 cubes,lol
Ahhh.. The magic of onboard computers. Don't for a minute think they would even come close today either, if it were not for computerized electronic ignition / fuel injection / fuel control / variable valve timing.

Old ones were doing pretty good with carbs / mechanical FI and points in the magnetos
 

dhay13

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And thats the biggest difference. In my Chevelle I had to run race fuel and it wasn't very driveable on the street. I drove it on the street but it wasn't fun after about 20 miles. Today you can make 700HP naturally aspirated and still drive it across country. My '57 wasn't as bad but it was only 552HP but it was a small block. Still not nearly as hard to drive as the Chevelle. But today 552HP is nothing for a daily driven car
 

Tray Burge

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We could only dream of having heads that flowed as good as the newer 6.4 heads flow
Sad thing is, back when I lived in Texas 20 years ago and I sold CNC's for HAAS, I knew the shop owner that had a contract with Hendricks Motor Sports to run all their Nascar racing heads with his highly secretive patented 5 axis port and polish program. If I had only had my truck back then...?
 
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