The car currently leaves with no discernable tire spin on ET Streets. My 14 year old son says it doesn��t look like the slicks are spinning, I don��t feel any slip behind the wheel, and the videos don��t show much either way. Based on this, I think I can hit the tires harder for a better launch and shave some time.

The car currently has new stock suspension (the Magna kit from Mustangs Plus) with Shelby under-ride bars. It has a Detroit Locker with 4.11s and a C6 with 18% lower first gear ratio (something approaching 4.30 equivalent in first gear). When the car leaves, the back squats a bit, the front rises a bit, and the car takes off pretty flat out of the lights.

Armed with my newfound ignorance based on the Door Slammers book, my instant center appears to be below my neutral line (hence the rear squat and front lift). I��m guessing I��m not overpowering the tires off the line (only 390 lb-ft torque in third gear at 3000 rpm based on chassis dyno). Therefore, can I pick up a tenth or two by playing with the instant center?

From what I understand, the Cal Tracs setup moves the instant center forward compared to stock so it likely won��t result in an increased hit to the rear tires. What options do I have to hit the tires harder and get a better jump out of the lights?

Thanks a bunch,

Scott

You're fairly close to where I live. I'd like to see your car sometime. Any local cruises happening this spring?

Anyway, what RPM are you leaving at now? From what i've learned here, to utilize your motor's full potential on launch, you want to launch your car at the motor's peak torque RPM level. So if your car made the most torque at say 4500, you'd want to launch at or near that. SteveW and Alex can get more specific to that matter.

Also, from what i've learned from Alex, SteveW and Co. you want the front to lift but the rear NOT to squat. The weight transfer to the rear will aid in "planting" the tires with the FULL weight of the car on the rear tires at the moment of launch.

Caltracs, again from what i've researched here, will transfer power faster to the tires without wrapup of the differential and springs. I've seen Melissa's and SteveW's '66 coupe barely lifting the front tires before they had the caltracs and monoleafs to lifting over a foot in the air and from what I recall made a difference in almost .4 - .5.

I hope I said that right, being away from this site made me forget this stuff a little. I'm glad to be browsing and posting again.

Erik

I kinda figured the rear squat wasn't helping much. Now that everything else is working, it's time to put some effort into the rear. Mono's and Cal Tracs are an option, I just want to make sure it's the right option. I don't get much wrap-up now thanks to the under-ride bars. I just need to know how to eliminate the squat.

Thanks,

Scott

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SCOOP

oddly obsessed with big scoops on little Mustangs

2.26 60'S
14.9 @ 90.86MPH

65 coupe,351w,C4,Big Boss 429 hood scoop,8" 3.40 TracLoc.

Door slammers is mostly geared to Ladder bar/4 link cars. If you don't want to back half the car get CalTracs, mono leaf springs, and Rancho 9000 shocks from John Calvert. John will personally help you with getting it set up right too. Order them from Alex and he'll help you too.

There've been many bracket races at Infineon when the back half cars with 14" wide slicks got loose and couldn't run the number against the leaf sprung 10" tired '66. Enough to make me think back halfing a car is not the only way to go.

Alex, looks like I need some cal tracs from you. How much do I need to send you???

Thanks,

quote:

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Originally posted by Scott (69Mach):
Zeater, I'm running 1.76s now coming off idle on the last amber.

Alex, looks like I need some cal tracs from you. How much do I need to send you???

Thanks,

Scott

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From M&Ms Classified Ads:

"Mustang Cal-Tracs always in stock. $317 plus shipping.
For product info click here http://www.calvertracing.com/

For ordering info e-mail me at [email protected]

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Alex Denysenko
Co-Administrator and Moderator"

Just remembered, if you haven't already done so, clamp the leafs on the front half of your leaf springs. If you do that before this weekend's run, you may see a noticeable difference in your times.

Just read your "New Times" thread and noticed that you already have a 3000 stall converter. Ever try leaving at 2500-2700 or so?

Erik

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1966 Ford Mustang 2+2
Father & Son built w/M&M Help

(Quote)
From what I understand, the Cal Tracs setup moves the instant center forward compared to stock so it likely won��t result in an increased hit to the rear tires. What options do I have to hit the tires harder and get a better jump out of the lights?
(endquote)

That's not true the caltracks are infinately adjustable, especially combined with good rear shocks. They can hit the tires real hard set on the top hole with a stiff shock setting and a lot of preload. We run them pretty soft so they won't blow the tires off on poor track surfaces. They have plenty of adjustability.

Also when you hit the tires harder things will get more unpredictable. Don't ask how I know.

I'm still coming off idle just because I'm still having to think about too many things at the line. I'm brand new to the game. Today I'll launch a few times off the converter and see how much that helps.