Previous Thread
Next Thread
Print Thread
Page 5 of 5 1 2 3 4 5
Re: Race Engine reality, what works [Re: dvw] #2736392
01/25/20 06:00 AM
01/25/20 06:00 AM
Joined: May 2008
Posts: 5,399
Aurora, Colorado
451Mopar Offline
master
451Mopar  Offline
master

Joined: May 2008
Posts: 5,399
Aurora, Colorado
Interesting topic, wish I knew the answers.
I just have a street car, so once I got to the mid 11's more power slowed my '60 times but added to top end MPH. Besides the car has no rollbar.
I do think the entire vehicle needs to be considered when making engine changes.
For example, is 10 more peak HP worth a loss of 20 ft/lbs in the mid range. If the converter and gear operate near peak HP, then it should be quicker. If your geared more for street with a tighter converter, than maybe not?
Since when I race it is just bracket racing, consistency is more important than running a specific number.
I try to find parts that don't create alot of problems. I have had several different sets of spark plug wires, all which ran about the same when new, but after time I have had them melt. crack, burn, have the terminal ends pull off, or not snap on well.
Currently using the Accel 9000 with ceramic ends. Haven't had them on that long, so I will see how they hold up.
Engine wise, I think many overlook using the correct length and type (diameter, material, thickness and hardening) of pushrods.
Controlling fluids like oil and fuel would be another. If your car pulls just 1G acceleartion, the fluids are going to flow to the rear of the oil pan, gas tank, and carb bowls as if the car was setting at a 45-degree angle.

Re: Race Engine reality, what works [Re: 451Mopar] #2736411
01/25/20 09:13 AM
01/25/20 09:13 AM
Joined: Jan 2003
Posts: 8,005
Tulsa OK
Bad340fish Offline
master
Bad340fish  Offline
master

Joined: Jan 2003
Posts: 8,005
Tulsa OK
One surprsing gain I had was tires. I ran a few weeks on a 28x10.5 stiff wall tire a friend gave me. I moved from that tire to a pro bracket radial in the same size and shaved a good .05-.08 off the 60ft time.

I run a high resolution driveshaft sensor and there was no traction problems with the bias tire. They did have a different curve on the driveshaft speed but I believe the difference was the sidewall wrapping up on the bias tire because it was at the hit and for a microsecond.

It ran better MPH on the bias tire but that is because the engine was tapped out on RPM due to a forced gear change(broken 8.75).

I am terrible at note taking and logging passes. My Dad takes all my slips at the end of the day and logs them into a spreadsheet with the splits on it(Thanks Dad!). But I don't add enough notes to look back a year or two and remember what I changed tsk

Last edited by Bad340fish; 01/25/20 09:14 AM.

68 Barracuda Formula S 340
87 "Chrysler" Conquest
Re: Race Engine reality, what works [Re: dvw] #2741214
02/09/20 01:12 PM
02/09/20 01:12 PM
Joined: Aug 2003
Posts: 1,310
Charlotte, NC
L
LSP Offline
pro stock
LSP  Offline
pro stock
L

Joined: Aug 2003
Posts: 1,310
Charlotte, NC
Where to start -

First, there are no "tricks", pay attention to the basics - quality machine work, quality induction work, quality piston/ring/cylinder sealing, reduce friction where you can, reduce oil flow/oil pump PSI when you can, use as large of an oil pan that will fit and only enough oil to maintain PSI through the run. correctly sized header primaries/merge collector.

The .9mm,.9mm, 3mm ring combo was 10 hp avg. better than the .043, .043, 3mm ring combo in a SBC in very controlled ABA conditions, not sure why your results didn't mirror those?

And that was with leaving the top ring in the same position - Another advantage with the smaller ring package is that the ring radial widths are .125" vs. .155", allowing the top ring position to be moved up on the piston, proven power there too.

Last edited by LSP; 02/09/20 01:20 PM.
Re: Race Engine reality, what works [Re: LSP] #2742058
02/11/20 07:28 PM
02/11/20 07:28 PM
Joined: Jan 2013
Posts: 174
H
hustlin hoosier Offline
member
hustlin hoosier  Offline
member
H

Joined: Jan 2013
Posts: 174
We have built set on kill engines of all sizes and have found air flow is king, we make the same hp with a 565 as we did with a 632. The thing with the 565 was it was much easier to race. e were definitely faster with the 565. these engines were raced in nmca 10.5 . we were normally in the top 1/3rd of the field qualifying . I would like to see where we out ran the head flow. It would be my guess around 520 inches. So with all that air flow is the name of the game in my opinion.

Re: Race Engine reality, what works [Re: hustlin hoosier] #2742067
02/11/20 08:05 PM
02/11/20 08:05 PM
Joined: Aug 2003
Posts: 43,007
Bend,OR USA
C
Cab_Burge Offline
I Win
Cab_Burge  Offline
I Win
C

Joined: Aug 2003
Posts: 43,007
Bend,OR USA
Originally Posted by hustlin hoosier
We have built set on kill engines of all sizes and have found air flow is king, we make the same hp with a 565 as we did with a 632. The thing with the 565 was it was much easier to race. e were definitely faster with the 565. these engines were raced in nmca 10.5 . we were normally in the top 1/3rd of the field qualifying . I would like to see where we out ran the head flow. It would be my guess around 520 inches. So with all that air flow is the name of the game in my opinion.
iagree up


Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
Page 5 of 5 1 2 3 4 5






Powered by UBB.threads™ PHP Forum Software 7.7.1