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Re: Which Is Faster

Posted: Mon Sep 25, 2017 8:10 am
by Warp Speed
Geoff2 wrote:I said on page 1 the 6200 rpm engine would be faster. Look forward to what DV has to say.
Congratulations, does that instantly make you correct in your assumptions?

Re: Which Is Faster

Posted: Mon Sep 25, 2017 8:50 am
by CGT
vortecpro wrote:
David Vizard wrote:
vortecpro wrote:I'am going to ask the same question I asked on the Chevelle forum.


"Which engine is faster down a dragstrip and why"




A 427 that makes 600 HP @ 6200 RPM
A 427 that makes 600 HP @ 7100 RPM

?
Absolutely and without doubt the 427 making 600 hp at 6200.

I will explain when I return from down under next week.

DV
David

Can you use those red letters in your post when you explain, I really like those. Be safe.
You don't like the yellow or blue? lol

Re: Which Is Faster

Posted: Mon Sep 25, 2017 9:33 am
by vortecpro
I like the red letters he use's when addressing my posts, infact its a topic of conversation around my shop and at lunch. But I was waiting and hoping David would get in here! Pretty sure Warp has something to say as well...............

Re: Which Is Faster

Posted: Mon Sep 25, 2017 11:27 am
by Krooser
Just wondering which engine would be faster in a dirt oval application?

I've never spun any of my engines over 6800 or so... I guess I really old school from way back when we didn't have the components that would hold up to that strain. Now my buddies spin 'em 7800 with SBC stock blocks or Dart block SHP with import cranks and rods... that just scares the hell outta me.

My 2018 deal will be a small block Mopar with a good Mopar forged crank, stock 340 bushed rods, 500 gram Ross pistons (or equivelant), solid flat tappet cam, W2 heads with Crower springs, Ti retainers and 3/8" valves... not today's lightest deal but good quality stuff.

My heads should flow close to 300 on the intake... the engine dyno'd at 575HP when new using an old Mopar purple shaft cam (don't know whch one).

This engine was originally built in '93 (for a WISSOTA A-mod), sat for many years under a guys work bench after his home track switched from dirt to pavement in '95. He loaned it out in '07 to a 'friend' who broke the cam the first night out. It went back to the original engine shop (good reputation) got a $3K freshen and then proceeded to blow it up after, what I think, was using too heavy of any oil with some 'goo' added to the oil. Seems he didn't warm up the engine on a cool fall night and spun a bearing but kept his hoof on the throttle until she seized a rod bearing.

Sorry for rambling... and hijacking this thread.

Re: Which Is Faster

Posted: Tue Sep 26, 2017 5:23 am
by Geoff2
Warp speed,
Thank you for your warm congratulations...

Re: Which Is Faster

Posted: Tue Oct 10, 2017 11:22 pm
by vortecpro
David Vizard wrote: Sun Sep 24, 2017 8:36 pm
vortecpro wrote:I'am going to ask the same question I asked on the Chevelle forum.


"Which engine is faster down a dragstrip and why"




A 427 that makes 600 HP @ 6200 RPM
A 427 that makes 600 HP @ 7100 RPM

?
Absolutely and without doubt the 427 making 600 hp at 6200.

I will explain when I return from down under next week.

DV
David

Can we get back to this.

Re: Which Is Faster

Posted: Wed Oct 18, 2017 9:08 pm
by cjperformance
:roll:

Re: Which Is Faster

Posted: Thu Oct 19, 2017 3:32 pm
by David Vizard
vortecpro wrote: Tue Oct 10, 2017 11:22 pm
David Vizard wrote: Sun Sep 24, 2017 8:36 pm
vortecpro wrote:I'am going to ask the same question I asked on the Chevelle forum.


"Which engine is faster down a dragstrip and why"




A 427 that makes 600 HP @ 6200 RPM
A 427 that makes 600 HP @ 7100 RPM

?
Absolutely and without doubt the 427 making 600 hp at 6200.

I will explain when I return from down under next week.

DV
David

Can we get back to this.

Sure, but let me ask first who, if any, have experience actually doing multiple track testing of a situation like this.

As it happens I have a couple of thousand laps of Silverstone testing Mini's (as well as about another couple of thousand testing and setting up other drivers cars) from 850 cc 87 hp & 74 lbs-ft through to 8 port 1000 cc screamers putting out 137 @ 11000 or so rpm to 1500 plus cc five port jobbies cranking out similar outputs.

For performance out of a slow bend and outright lap times showed that for a given hp the big torque motor wins every time.

It's all to do with the MOI of the parts involved and an analysis of such indicated the theoretical results are emulated by those found on the track. It is not by much but the mean deviation of my lap times is much less than the difference between tests so the results pretty solid. Remember all of these cars were Mini's mostly with all else very similar or the same between each vehicle. In many cases it was the same vehicle. I got to select the final drive ratio in all cases and for this I used the power curve versus total drag with the data run through a Sinclair calculator. And BTW for about 7 years I was the second fastest Mini around the 'Stone and that really ticked me off.
DV

Re: Which Is Faster

Posted: Thu Oct 19, 2017 4:05 pm
by digger
That isn't isn't answering the question pertaining to drag strip though

Re: Which Is Faster

Posted: Thu Oct 19, 2017 4:14 pm
by cjperformance
vortecpro wrote: Sun Sep 17, 2017 6:01 pm I'am going to ask the same question I asked on the Chevelle forum.


"Which engine is faster down a dragstrip and why"





A 427 that makes 600 HP @ 6200 RPM
A 427 that makes 600 HP @ 7100 RPM

?
This is about a Drag strip test/ from a standing start!

Re: Which Is Faster

Posted: Fri Oct 20, 2017 12:03 am
by vortecpro
David

Thanks for responding. I hope in the future you will use the "RED" letters when you respond to my posts. I really enjoyed your small block Chevy book where you built the low dollar combinations, information you can use, probably could partially blame you for my desire to port production heads, and work with production parts. My memory isn't that good but I can remember the articles on ported BBC heads around the K&N days, or the ported 186s which I always aspired to get 260 CFM out of per your book. I used to work the junk yards like a boss back in the day, and still do but its not the same. Your definitely a engine guy and that's a good thing.

Re: Which Is Faster

Posted: Fri Oct 20, 2017 1:47 am
by GARY C
vortecpro, when you say K&N are you referring to his filter testing? I was just curious because I actually have that filter and case, it was in the trunk of the car when I acquired it.

Re: Which Is Faster

Posted: Fri Oct 20, 2017 1:53 am
by vortecpro
Yes

Re: Which Is Faster

Posted: Fri Oct 20, 2017 1:55 am
by GARY C
vortecpro wrote: Fri Oct 20, 2017 1:53 amYes
I added the pictures, maybe after your post

Re: Which Is Faster

Posted: Fri Oct 20, 2017 9:26 am
by vortecpro
GARY C wrote: Fri Oct 20, 2017 1:55 am
vortecpro wrote: Fri Oct 20, 2017 1:53 amYes
I added the pictures, maybe after your post
I remember that 13 sec engine tester. Ahh the good ole days!