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Old 11-19-2020, 11:32 AM
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Originally Posted by i82much View Post
I am curious whether you are considering beehive springs and lightweight retainers? have read some about getting more high rpm power that way.
No just small diameter springs with light retainers

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Old 11-19-2020, 11:44 AM
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580 to 590 hp. 590 to 600 tq.

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Old 11-19-2020, 12:24 PM
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Originally Posted by slowbird View Post
No just small diameter springs with light retainers
thanks, looking forward to results!

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Old 11-19-2020, 12:35 PM
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I built one very similar that made 585hp on Kauffman's dyno. Had T2 intake/850 Holley though. Later switched to 950 custom built from Pro Systems and I wish we could have put it on the dyno again. It definitely made way more power.

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Old 11-19-2020, 02:25 PM
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Originally Posted by Hillard View Post
I built one very similar that made 585hp on Kauffman's dyno. Had T2 intake/850 Holley though. Later switched to 950 custom built from Pro Systems and I wish we could have put it on the dyno again. It definitely made way more power.
Cam specs? Hyd roller lifters or solid?

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Old 11-19-2020, 03:43 PM
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Example for interest....

4.212 bore
4.250 stroke
6.8 rods
473 CID
Edelbrock heads- rated 316 cfm at .700"
2.110 / 1.770 valves
9.95:1 compression
Comp hydraulic roller cam
242 / 248 at .050
0.540 / 0.562* lift w/ 1.5 rocker ratio
Victor intake w/ 1-inch open spacer / BG 850 carb
1.750" headers
92-octane fuel

588 ft.lbs torque at 4700 rpm
578 hp at 5500 rpm

After digesting the results, David Butler comments, "The numbers look very good. We've seen 600 hp and 600 lb-ft of torque, sometimes slightly more from this combination with compression toward 11.5:1, which should operate suitably on 92- to 93-octane fuel with the aluminum heads. This wasn't a 'dyno' combo, however, which might typically include borderline compression, a huge camshaft, and a large carburetor. Instead, we took a conservative approach based on the vehicle's intended use."


.

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Old information here:
http://www.hotrod.com/articles/0712p...tiac-trans-am/

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Old 11-19-2020, 05:07 PM
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Quote:
Originally Posted by Steve C. View Post
Example for interest....

4.212 bore
4.250 stroke
6.8 rods
473 CID
Edelbrock heads- rated 316 cfm at .700"
2.110 / 1.770 valves
9.95:1 compression
Comp hydraulic roller cam
242 / 248 at .050
0.540 / 0.562* lift w/ 1.5 rocker ratio
Victor intake w/ 1-inch open spacer / BG 850 carb
1.750" headers
92-octane fuel

588 ft.lbs torque at 4700 rpm
578 hp at 5500 rpm

After digesting the results, David Butler comments, "The numbers look very good. We've seen 600 hp and 600 lb-ft of torque, sometimes slightly more from this combination with compression toward 11.5:1, which should operate suitably on 92- to 93-octane fuel with the aluminum heads. This wasn't a 'dyno' combo, however, which might typically include borderline compression, a huge camshaft, and a large carburetor. Instead, we took a conservative approach based on the vehicle's intended use."


.
Interesting choice in intake for the build. Guess i wouldn't consider the Victor for a mild combo like that.

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Old 11-19-2020, 06:48 PM
Steve C. Steve C. is offline
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The Victor intake doesn't grossly sacrifice as much low-speed throttle response as many believe it does. On my previous 462 pump gas engine at 3500 rpm the Performer RPM intake made only 4 ft.lbs more torque than the Victor intake. And at their respective peak power rpm they were within 6 ft.lbs torque of each other, but as expected the Victors peak torque rpm was higher than the Performer RPM intake by 200-300 rpm depending on the dyno pull. And the Victor intake made peak power 200 rpm higher, with an additional 20 hp over the Performer RPM intake. But obviously much depends on the combination involved, mine was a 600 HP engine with the Victor intake.

The total plenum volume of the Victor intake is 946 cc's vs the Torker II with 1195 cc's. And the Victor intakes average runner length is only 0.75" longer than the Torker II intake.

.

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'70 TA / 505 cid / same engine but revised ( previous best 10.63 at 127.05 )
Old information here:
http://www.hotrod.com/articles/0712p...tiac-trans-am/

Sponsor of the world's fastest Pontiac powered Ford Fairmont (engine)
5.14 at 140 mph (1/8 mile) , true 10.5 tire, stock type suspension
https://www.youtube.com/watch?v=qDoJnIP3HgE

Last edited by Steve C.; 11-19-2020 at 06:57 PM.
  #29  
Old 11-22-2020, 10:50 PM
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How much does the compression come into play for the numbers .....I have a 461 with 340 heads and I was hoping for 650hp but I’m only at 10:1

  #30  
Old 11-23-2020, 10:15 AM
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I've built combos very similar to that in the past and dyno'd them.

I don't believe it'll hit 600hp, with that cam, heads, and intake on an honest dyno.
None of them I've been involved with ever did unless something like the cam and intake profiles were changed around.

More like 570-580hp, but it will make boat loads of torque, likely over 600 ft lbs.

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  #31  
Old 11-23-2020, 08:11 PM
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Quote:
Originally Posted by Formulajones View Post
I've built combos very similar to that in the past and dyno'd them.

I don't believe it'll hit 600hp, with that cam, heads, and intake on an honest dyno.
None of them I've been involved with ever did unless something like the cam and intake profiles were changed around.

More like 570-580hp, but it will make boat loads of torque, likely over 600 ft lbs.
That sounds like a challenge, i accept. Lol.

  #32  
Old 11-24-2020, 11:06 AM
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Originally Posted by slowbird View Post
That sounds like a challenge, i accept. Lol.


Wasn't knocking the combo, I've actually liked that particular setup for a nice street engine. Just that they don't tend to reach 600hp like that, and that's okay.

I've done 463-467ci with conventional style 320-330 cfm heads, usually round ports but the KRE D-ports you're using are similar. My favorite cam in a few different engines is the 242/248 grind very similar to what you're using, and I almost always use that RPM intake with a 950hp carb. Those engines I've done all used 2" headers though, not smaller 1 3/4 that you have.
The Pontiac just simply peaks around 570-580hp like I mentioned, usually around 5800-6000 rpm but they make boat loads of torque. Very table top flat and just over 600 ft lbs. It's a great street engine and will run mid to low 11's in a 4000 lbs street car out here.
Now if you were to step up the heads to a high port, or some serious porting on the conventional head, and maybe a little more cam, or a good single plane intake to push peak HP and rpm up a bit, I could see it. When using the RPM intake, I had to use a 1" open spacer to get the peak HP up where I predicted for your combo, but it still wasn't 600hp.

The only way I've been able to top 600hp with similar combos like that is with a BBC. 461 ci, 10.2:1 compression, RPM air gap intake and 950HP, again with 2" hooker super comp headers, and the same 242/248 camshaft, but with far superior AFR heads that flow 370 cfm, but they are still a conventional BBC head with nothing fancy. It makes 612hp up at 6300 rpm but it simply doesn't make the torque like a Pontiac, in the 580 range at a higher rpm. It's really the cylinder heads that are doing it. Far better than a conventional Pontiac head, so I don't need as much camshaft to make more HP. Personally I like the torque curve of the Pontiac. Not knocking your combo, it's a great all around package that isn't too rowdy.

Now you may find a dyno that'll move the numbers around a bit, but it is what it is. I'd like to see a video and dyno sheet, as long as they give you BSFC and LBS. per hr numbers.

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  #33  
Old 11-24-2020, 12:43 PM
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Quote:
Originally Posted by Formulajones View Post


Wasn't knocking the combo, I've actually liked that particular setup for a nice street engine. Just that they don't tend to reach 600hp like that, and that's okay.

I've done 463-467ci with conventional style 320-330 cfm heads, usually round ports but the KRE D-ports you're using are similar. My favorite cam in a few different engines is the 242/248 grind very similar to what you're using, and I almost always use that RPM intake with a 950hp carb. Those engines I've done all used 2" headers though, not smaller 1 3/4 that you have.
The Pontiac just simply peaks around 570-580hp like I mentioned, usually around 5800-6000 rpm but they make boat loads of torque. Very table top flat and just over 600 ft lbs. It's a great street engine and will run mid to low 11's in a 4000 lbs street car out here.
Now if you were to step up the heads to a high port, or some serious porting on the conventional head, and maybe a little more cam, or a good single plane intake to push peak HP and rpm up a bit, I could see it. When using the RPM intake, I had to use a 1" open spacer to get the peak HP up where I predicted for your combo, but it still wasn't 600hp.

The only way I've been able to top 600hp with similar combos like that is with a BBC. 461 ci, 10.2:1 compression, RPM air gap intake and 950HP, again with 2" hooker super comp headers, and the same 242/248 camshaft, but with far superior AFR heads that flow 370 cfm, but they are still a conventional BBC head with nothing fancy. It makes 612hp up at 6300 rpm but it simply doesn't make the torque like a Pontiac, in the 580 range at a higher rpm. It's really the cylinder heads that are doing it. Far better than a conventional Pontiac head, so I don't need as much camshaft to make more HP. Personally I like the torque curve of the Pontiac. Not knocking your combo, it's a great all around package that isn't too rowdy.

Now you may find a dyno that'll move the numbers around a bit, but it is what it is. I'd like to see a video and dyno sheet, as long as they give you BSFC and LBS. per hr numbers.
Didn't take it as you knocking it. My guess is 560-580 also. I was missing around about the challenge. The bsfc and lbs will be posted so you can figure out the raw power if you like. With a better short block i do think 600hp with a combo like this is achievable though.

  #34  
Old 11-24-2020, 02:15 PM
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What does the gross valve lift calculate at? What I see with many with these good flowing head builds is not taking full advantage of the higher lift flow capability at .600 plus. My heads flow 314cfm at .600..with a 236/246 dur ..391/.400 lobe lift cam with 1.65 Harland Sharpes at 10.8 to 1 compression. This combination has produced well over 600hp in dyno tests by the head porter. I think the limiting factor is the dual plane intake for a true 600hp build in the OP case. The build is easily attainable but make use of the higher lift flow available,get the valve lift in the 650 to 670 range, use available valve spring packages to control higher rpm use and its there.

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466 Mike Voycey shortblock, 310cfm SD KRE heads, SD "OF 2.0 cam", torker 2
373 gears 3200 Continental Convertor
best et 10.679/127.5/1.533 60ft
308 gears best et 10.76/125.64/1.5471
  #35  
Old 11-24-2020, 02:21 PM
Steve C. Steve C. is offline
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X2 ta man

Excellent post !

David Vizard is a big proponent of valve lift and points out a typical 2-valve ported cylinder head responds to valve lift without a sacrifice of idle and low speed qualities.

So is Tilden Technologies:

"Once the four timing parameters are established, the cam should be designed for maximum lift."



.

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'70 TA / 505 cid / same engine but revised ( previous best 10.63 at 127.05 )
Old information here:
http://www.hotrod.com/articles/0712p...tiac-trans-am/

Sponsor of the world's fastest Pontiac powered Ford Fairmont (engine)
5.14 at 140 mph (1/8 mile) , true 10.5 tire, stock type suspension
https://www.youtube.com/watch?v=qDoJnIP3HgE

Last edited by Steve C.; 11-24-2020 at 02:30 PM.
  #36  
Old 11-24-2020, 02:40 PM
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I bet you will fall within the two lines. 482 Buick but similar build

Sent from my SM-T817V using Tapatalk

  #37  
Old 11-24-2020, 02:41 PM
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Net lift should be .630-.640 (.398 x 1.65 minus hyd lifter give). Springs will be Pac 1255 (assuming we can get them to fit, they're used from a previous build)

  #38  
Old 11-24-2020, 02:50 PM
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Quote:
Originally Posted by Steve C. View Post
X2 ta man

Excellent post !

David Vizard is a big proponent of valve lift and points out a typical 2-valve ported cylinder head responds to valve lift without a sacrifice of idle and low speed qualities.

So is Tilden Technologies:

"Once the four timing parameters are established, the cam should be designed for maximum lift."



.
Thanks Steve. 600 hp and close to 20mpg is achievable with pump gas..with a mild 235/236 duration...try saying that 20 years or even 10 years ago.

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466 Mike Voycey shortblock, 310cfm SD KRE heads, SD "OF 2.0 cam", torker 2
373 gears 3200 Continental Convertor
best et 10.679/127.5/1.533 60ft
308 gears best et 10.76/125.64/1.5471
  #39  
Old 11-24-2020, 03:32 PM
Steve C. Steve C. is offline
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See my post number 16.... add some additional cfm flow to the heads and a bit more compression (if desired, but maybe not necessary) and...... 600 hp.

.

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'70 TA / 505 cid / same engine but revised ( previous best 10.63 at 127.05 )
Old information here:
http://www.hotrod.com/articles/0712p...tiac-trans-am/

Sponsor of the world's fastest Pontiac powered Ford Fairmont (engine)
5.14 at 140 mph (1/8 mile) , true 10.5 tire, stock type suspension
https://www.youtube.com/watch?v=qDoJnIP3HgE
  #40  
Old 12-02-2020, 08:27 PM
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Cam is officially ordered and on the way. Just need to finish some details with heads/valvetrain then its just scheduling the dyno.

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