Horsepower/Torque estimate
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Horsepower/Torque estimate
455 standard bore.
9.5:1 compresssion
Comp cams 280H - 230 int/230 exh @ .050. .490” lift on both. 110 LSA.
J heads with stock rockers and Comp Cams double valve springs. Pocket ported. Heat risers plugged. Otherwise stock.
Edelbrock Performer
870 Street Avenger
Headers
Stock HEI
9.5:1 compresssion
Comp cams 280H - 230 int/230 exh @ .050. .490” lift on both. 110 LSA.
J heads with stock rockers and Comp Cams double valve springs. Pocket ported. Heat risers plugged. Otherwise stock.
Edelbrock Performer
870 Street Avenger
Headers
Stock HEI
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Joined: May 2018
Posts: 782
My estimates are based on Crankshaft numbers, not a chassis Dyno
My guess on a chassis Dyno would be based on what transmission, torque converter diameter and stall speed (and brand), and what rear differential is being ran (GM or FORD and diameter), and what tires and air pressure is being ran.
On a chassis dyno, running a GM400 trans, a 2500rpm 11 inch converter (decent TCI or better), and an 8.5 inch 10 bolt with 3.42 gearing and 27 inch tires with 35psi..... I would guess ........... 250-270whp/350lb ft
My guess on a chassis Dyno would be based on what transmission, torque converter diameter and stall speed (and brand), and what rear differential is being ran (GM or FORD and diameter), and what tires and air pressure is being ran.
On a chassis dyno, running a GM400 trans, a 2500rpm 11 inch converter (decent TCI or better), and an 8.5 inch 10 bolt with 3.42 gearing and 27 inch tires with 35psi..... I would guess ........... 250-270whp/350lb ft
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I agree, around 370 at the crank with 460-470 lbs/ft torque. It sounds like a stout reliable machine!!!! The one thing that really pumped my H.P. and Dyno numbers up were a Lunati Voodoo hyd. roller cam, icon pistons (10:5/1) Edelbrock heads for hyd. roller and an air-gap intake. They all work well to the tune of 531 H.P. and 576lbs/ft torque at the crankshaft. Both figures came in at a fairly low RPM. Wayne
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Got this engine running. Only been around the block but very pleased so far.
However ended up using an Erson cam and didn’t block the heat risers. Also using a 1” spacer under the carb, and used a block with 60 over bore
Cam is a single pattern 228 @ .050 with .504 108 LSA. Degreed in at 104.5. Very happy with it.
However ended up using an Erson cam and didn’t block the heat risers. Also using a 1” spacer under the carb, and used a block with 60 over bore
Cam is a single pattern 228 @ .050 with .504 108 LSA. Degreed in at 104.5. Very happy with it.
Last edited by VinMichael; Aug 28, 2018 at 06:59 PM.
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You and me both! I tell people the same thing. I bought the car with a very average 8:1 350 when I was 17 and that’s what stayed there. Never even driven a 455 until now.
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This week I picked up a set of Edelbrock heads part number 60519 on Craigslist. They are brand new and never been out out the box.
I have a set of PRW steel 1.65 ratio rockers for them.
Does anyone have an estimate for what the gain would be after swapping the heads? It runs good but want more.
Oh and I ended up going with a slightly different cam. Erson 228/228 @ .050, .504” lift, 108 LSA. Installed @ 104. And ended up using a .060 over block.
I have a set of PRW steel 1.65 ratio rockers for them.
Does anyone have an estimate for what the gain would be after swapping the heads? It runs good but want more.
Oh and I ended up going with a slightly different cam. Erson 228/228 @ .050, .504” lift, 108 LSA. Installed @ 104. And ended up using a .060 over block.
Last edited by VinMichael; Feb 8, 2019 at 01:29 PM.
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Joined: May 2018
Posts: 782
This week I picked up a set of Edelbrock heads part number 60519 on Craigslist. They are brand new and never been out out the box.
I have a set of PRW steel 1.65 ratio rockers for them.
Does anyone have an estimate for what the gain would be after swapping the heads? It runs good but want more.
Oh and I ended up going with a slightly different cam. Erson 228/228 @ .050, .504” lift, 108 LSA. Installed @ 104. And ended up using a .060 over block.
I have a set of PRW steel 1.65 ratio rockers for them.
Does anyone have an estimate for what the gain would be after swapping the heads? It runs good but want more.
Oh and I ended up going with a slightly different cam. Erson 228/228 @ .050, .504” lift, 108 LSA. Installed @ 104. And ended up using a .060 over block.
i would guesstimate you will be closer to 420-430 Hp now if the compression is 9:1
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Good point the comp ratio will be higher, I forgot they have 77cc chambers.
I can add a .027 head gasket while I’m at it. Then compression will be 10 - 10.2:1
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From: Central Fl
[QUOTE=VinMichael;1153475]
thanks man, yeah I paid $1,000.
Good point the comp ratio will be higher, I forgot they have 77cc chambers.
I can add a .027 head gasket while I’m at it. Then compression will be 10 - 10.2:1
Every little bit helps!
Good point the comp ratio will be higher, I forgot they have 77cc chambers.
I can add a .027 head gasket while I’m at it. Then compression will be 10 - 10.2:1
Every little bit helps!
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Joined: May 2018
Posts: 782
Wow! awesome deal!
Yes, get the quench tighter and increase compression as much as you can,
you might be in the 450hp+ range at that point, depending on how far below deck your pistons are and how good the tune is
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As for the tune. I have an AEM wide band O2 sensor to install once I get the car back from the paint shop.
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