Re: Which Is Faster - 600hp@6200 or 600hp@7100
Posted: Wed Nov 08, 2017 11:50 am
$50 says this goes 30 pages...........
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Which Is Faster - 600hp@6200 or 600hp@7100
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Re: Which Is Faster - 600hp@6200 or 600hp@7100
Posted: Wed Nov 08, 2017 11:52 am
Perfect example Randy. That shows why RPM is king and none of this 28 pages of drivel. Thank You.
Re: Which Is Faster - 600hp@6200 or 600hp@7100
Posted: Wed Nov 08, 2017 12:12 pm
Randy,randy331 wrote: ↑Wed Nov 08, 2017 11:46 am While this won't answer the OP question specifically, it may be an interesting observation.
I did a 383 ( Pseudo ) and a 355 that both made 525 peak HP. Pseudo made peak HP at 6000 rpm while the 355 made peak HP at 7200 rpm.
Both went in powerglide, Coan converter cars. Pseudo had 4.56 rear end gear and the 355 5.43. Both 30" tall tires.
Weight was 2950 for pseudo and 3000 for the 355.
TQ at peak HP rpm would be 460 LBs for pseudo and 383 LBs for the 355 at peak HP rpm.
Pseudo ran a best
1.368 60'
6.38 @ 105.2 1/8 mile
10.24 @ 127 MPH
The 355 ran a best
1.349 60'
5.37 @ 106 1/8 mile
10.11 @ 130 1/4 mile
In my experience the set in the car favored Pseudo, yet the 355 produced better ET and MPH.
With less TQ at all locations on the track, why is the 355 faster ?
Randy
What was the stall for each?
Stan
Re: Which Is Faster - 600hp@6200 or 600hp@7100
Posted: Wed Nov 08, 2017 12:45 pm
Randy,randy331 wrote: ↑Wed Nov 08, 2017 11:46 am While this won't answer the OP question specifically, it may be an interesting observation.
I did a 383 ( Pseudo ) and a 355 that both made 525 peak HP. Pseudo made peak HP at 6000 rpm while the 355 made peak HP at 7200 rpm.
Both went in powerglide, Coan converter cars. Pseudo had 4.56 rear end gear and the 355 5.43. Both 30" tall tires.
Weight was 2950 for pseudo and 3000 for the 355.
TQ at peak HP rpm would be 460 LBs for pseudo and 383 LBs for the 355 at peak HP rpm.
Pseudo ran a best
1.368 60'
6.38 @ 105.2 1/8 mile
10.24 @ 127 MPH
The 355 ran a best
1.349 60'
5.37 @ 106 1/8 mile
10.11 @ 130 1/4 mile
In my experience the set in the car favored Pseudo, yet the 355 produced better ET and MPH.
With less TQ at all locations on the track, why is the 355 faster ?
Randy
If both convertor locked up / zero slippage the 355 @ 130 MPH is turning about 7900 and the 383 @ 127 MPH is turning about 6500 RPM. I would really want to see what each of those HP / Torque curves looked like after peak HP.
Stan
Re: Which Is Faster - 600hp@6200 or 600hp@7100
Posted: Wed Nov 08, 2017 1:44 pm
The answer is obvious, and has been mentioned at least 90 times in this thread. But I like how you ask questions with a question. It makes people THINK. Thanks for posting this.randy331 wrote: ↑Wed Nov 08, 2017 11:46 am While this won't answer the OP question specifically, it may be an interesting observation.
I did a 383 ( Pseudo ) and a 355 that both made 525 peak HP. Pseudo made peak HP at 6000 rpm while the 355 made peak HP at 7200 rpm.
Both went in powerglide, Coan converter cars. Pseudo had 4.56 rear end gear and the 355 5.43. Both 30" tall tires.
Weight was 2950 for pseudo and 3000 for the 355.
TQ at peak HP rpm would be 460 LBs for pseudo and 383 LBs for the 355 at peak HP rpm.
Pseudo ran a best
1.368 60'
6.38 @ 105.2 1/8 mile
10.24 @ 127 MPH
The 355 ran a best
1.349 60'
5.37 @ 106 1/8 mile
10.11 @ 130 1/4 mile
In my experience the set in the car favored Pseudo, yet the 355 produced better ET and MPH.
With less TQ at all locations on the track, why is the 355 faster ?
Randy
Re: Which Is Faster - 600hp@6200 or 600hp@7100
Posted: Wed Nov 08, 2017 3:59 pm
It's funny last time I accelerated an engine through the gears it was at the peak hp rpm for a very very short period of time. Hence you will never understand what's going on unless you know what happens before and after the peak rpm as it's the cumulative effect that matters not what happens at an instantaneous moment
Also it gave up a full second at the 1/8?
Also it gave up a full second at the 1/8?
Re: Which Is Faster - 600hp@6200 or 600hp@7100
Posted: Thu Nov 09, 2017 9:21 pm
Thought I'd make a correction on this.
The 355 didn't run a 5.37 @ 106 in the 1/8 mile.
It ran a 6.37 @ 106
But I'd guess most anyone that has drag raced would have figured that out.
Probably be kinda hard to run a 5.37 @ 106 then also run a 10.11 @ 130 on the same pass.
Randy
Re: Which Is Faster - 600hp@6200 or 600hp@7100
Posted: Thu Nov 09, 2017 11:25 pm
I thought a second quicker seemed really goodrandy331 wrote: ↑Thu Nov 09, 2017 9:21 pmThought I'd make a correction on this.
The 355 didn't run a 5.37 @ 106 in the 1/8 mile.
It ran a 6.37 @ 106
But I'd guess most anyone that has drag raced would have figured that out.
Probably be kinda hard to run a 5.37 @ 106 then also run a 10.11 @ 130 on the same pass.
Randy
Any idea what the average tq was in the used rpm range of these 2 combos?
Re: Which Is Faster - 600hp@6200 or 600hp@7100
Posted: Fri Nov 10, 2017 10:01 am
That would be good.
I don't know where the sheet to the 355 is right now. It wasn't down loaded and put on computer with the others.
Randy
Re: Which Is Faster - 600hp@6200 or 600hp@7100
Posted: Fri Nov 10, 2017 10:08 am
5800 rpm for 355 and 5700 rpm for 383.
Coan said the 355 needed 6400-6500 for best et, but we never tried it. He had me build bigger engine instead.
They said 5500-5600 for best et with 383.
That's part of why I said the set-up in the cars favors the 383.
In my experience, a little too much stall speed is better than not enough, especially in a powerglide car.
Randy
Re: Which Is Faster - 600hp@6200 or 600hp@7100
Posted: Fri Nov 10, 2017 11:11 am
60' -0.019
1/8 -.01
1/4 -.13
Odd that the 1/8th time shows there should have been minimal difference @ 1/4 mile.
So many variables. If you're saying the wider powerband is easier to get the gearing/converter etc. right, that's probably true.
Re: Which Is Faster - 600hp@6200 or 600hp@7100
Posted: Fri Nov 10, 2017 11:59 am
Had the 355 had 6500 rpm stall speed (like Coan said it needed after looking at the dyno sheet ) with a custom cnc billet stator the 1/8 mile ET would be better.
Better power curves are of course a plus, but I have little doubt the 355 had more ET left on the table than the 383 did.
Randy
Re: Which Is Faster - 600hp@6200 or 600hp@7100
Posted: Fri Nov 10, 2017 12:27 pm
AMEN on stall speed.randy331 wrote: ↑Fri Nov 10, 2017 10:08 am5800 rpm for 355 and 5700 rpm for 383.
Coan said the 355 needed 6400-6500 for best et, but we never tried it. He had me build bigger engine instead.
They said 5500-5600 for best et with 383.
That's part of why I said the set-up in the cars favors the 383.
In my experience, a little too much stall speed is better than not enough, especially in a powerglide car.
Randy
Re: Which Is Faster - 600hp@6200 or 600hp@7100
Posted: Fri Nov 10, 2017 5:31 pm
Re: Which Is Faster - 600hp@6200 or 600hp@7100
Posted: Fri Nov 10, 2017 7:14 pm
Fifteen posts on this page! A couple more and we'll hit the magic thirty that stealth forecast! 