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Discussion Starter #1 (Edited)
'77 2 bolt block, .060 bore, .005 deck height, H693CP60 -20.0cc dome, '72 3999241 heads 113cc chambers for 10.3:1 compression.
Manley Street Flo 2.19/1.88, Crane springs, Comp 11-671-4 Nostalgia+ LS6 solid lifter cam, Crane roller rockers
Edelbrock RPM Air Gap oval port manifold, Holley 750 double pumper modified by Raube Wan, 110 race gas
Pertronix HEI, Moroso 8mm wires, AC plugs

To tell you the truth I was expecting between 450 and 475 hp, the builder predicted 425. To say I'm pleasantly surprised is an understatement. The builder said if he would have thought it would make this kind of power he would have talked me into spending more money on the rotating assembly.

later, dozer
695145
695146
 

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'77 2 bolt block, .060 bore, .005 deck height, H693CP60 -20.0cc dome, '72 3999241 heads 113cc chambers for 10.3:1 compression.
Manley Street Flo 2.19/1.88, Crane springs, Comp 11-671-4 Nostalgia+ LS6 solid lifter cam, Crane roller rockers
Edelbrock RPM Air Gap oval port manifold, Holley 750 double pumper modified by Raube Wan, 110 race gas
Pertronix HEI, Moroso 8mm wires, AC plugs

To tell you the truth I was expecting between 450 and 475 hp, the builder predicted 425. To say I'm pleasantly surprised is an understatement. The builder said if he would have thought it would make this kind of power he would have talked me into spending more money on the rotating assembly.

later, dozer
View attachment 695145 View attachment 695146
Nice nr’s!
 

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Would help if you put up the complete screen,,,,,
What are those two columns supposed to be?
If HP & Torque something is very wrong with that dyno,,,,,,,,
 

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Discussion Starter #5
Would help if you put up the complete screen,,,,,
What are those two columns supposed to be?
If HP & Torque something is very wrong with that dyno,,,,,,,,
He's going to run it one more time this morning when the air is cool. I'll post the video and complete print out after I pick the engine up.

later, dozer
 

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Is that 578hp? Congrats.

There was a similar build to this one on here in the past. Wish I could remember who posted it to compare the #'s.
 

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Looks good!
Let us know how it runs.
 

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Discussion Starter #13
This is who built my engine, I chose the components and built the carb out of spare parts. They do a lot of race motors for dirt track and truck pulls. Great people, quality work and fair prices. His next dyno pull should be a 392 Hemi. They're also on Facebook you should check out their dyno videos.
Thanks to Tony, Lexi and Bill!


later dozer
 

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Discussion Starter #14
Oh lucky day! The parts car I've got parked in the south forty had a 307, so it had the tall frame mounts in it. The 396 was riding on smallblock mounts. Not my work.

later, dozer
 

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You might want to check the dyno there. Typically the peak TQ at say 5000 rpm is about 80% at 3,000 rpm. So 80% of 578 is like 462 you are like 362. A 270 hp increase from 4,200 to 5,500 is another issue (practically double the HP in 1,300 rpms). Also the peak TQ and HP of only 400 rpm is another issue typically around 1,500 rpm delta. Guys with other BBC engine dyno chime in here on what % you have on yours given a 5,500 rpm peak power is yours at 3,000 rpm. I think your/engine builder previous estimate is about right.
 

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I dont want to knock the build as those are respectable numbers but the torque seems low in the lower rpm range. With a 239/246 cam and 112 lsa in that combo I would expect a broader fatter torque curve. For comparison, while similar and not apples to apples, my 461 10:1 229/241 109 lsa was at 560 lbft at 3000rpm peaking at 4100 with 578. HP peak was around 6k. If it rips on the street then this is a moot observation but I think its worth looking at.
 

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Discussion Starter #17 (Edited)
I watched him make that run and I don't know anything about dyno operation but it seemed to me like he eased into throttle instead of just going wide open in a flash. He has many of his dyno videos on the Victory Engine and Machine Facistbook page. He's highly respected in the area with a lot of winning engines on dirt tracks in four states. I've got the final dyno sheet but have been waiting for the video to post it. This is my first engine dyno, I've put several of my bikes on chassis dynos. The sheet is Greek to me compared to anything I've ever seen before. Maybe I can get that video here in the next couple of days and post it.

later, dozer

p.s. I don't Fascistbook
 

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Discussion Starter #18 (Edited)
Here's the chart, I'll try to get my hands on the video. Looks like: [email protected] and [email protected]
He said he was afraid to take it any high because we didn't build the bottom end to handle these numbers and didn't want to scatter it. Remember, we were expecting less than 500hp.

later, dozer
 

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I'm guessing your dyno operator tried different timing? we only did 5-6 pulls on my 489 but it liked 35* at 3500 and from 34* to 35* it added a few tq #s but lowered hp #s a couple numbers, I didn't get the different columns either, I only understood HP & TQ LOL, last bike chassis dyno I did the clutches started slipping, made a funny looking graph (y)
 

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Discussion Starter #20
I'm guessing your dyno operator tried different timing? we only did 5-6 pulls on my 489 but it liked 35* at 3500 and from 34* to 35* it added a few tq #s but lowered hp #s a couple numbers, I didn't get the different columns either, I only understood HP & TQ LOL, last bike chassis dyno I did the clutches started slipping, made a funny looking graph (y)
I think he made 4 runs setting it up and the fifth run for the money. I got to see two of the runs
 
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