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Discussion Starter · #1 ·
Well I got the Hoosier Quick Time Pro DOT's and do they every bite! I ran 3 runs on them and noticed that they had spun on the rim. They were originally mounted with the "I" in Hoosier aligned with the valve stem. I have tubes installed and used 20lbs of air for each run.



The above tire rotated 4 1/2". The driver's side only 1". Time to drill and add screws.

The Hoosier's did drop half a second off my old 60's and nearly 1 1/2 seconds off the quarter from my normal street tires!

The best run of the night was the first. [email protected] with a 1000rpm launch, little to no apparent spin in first gear.

60'=2.023
330'=5.449
1/8th'[email protected]
1000'=10.630
1/4=12.62

The other 2 launches were at 3000 (spinning in first) and the next best was [email protected] with a 2.015 60'. Not quite sure what happened to the mph in that run, but the 3rd run was [email protected] with a 2.056 60'.

Luckily (???) I had brought along my old slippery bias street tires to finish out the night. Much more fun to launch, but absolutely no traction in first and second gears at full throttle in any rpm. Best was a [email protected] with a 2300rpm launch and a 2.603 60'.

I never was good at being consistent, but I have a lot of fun!


Before my next trip to the track, I plan on replacing my KYB shocks with the Rancho's and hopefully get to play with the Caltracs and work more on my launch technique.

_________________
Dennis

65' STANG, 3160 lbs

393W, 2.78 Toploader 4 Spd, 9" 3:70 Posi
Pro Comp Heads, Vic Jr. Intake, 750dp, 236/561 Solid Cam, 9.6CR, 1 3/4" Headers, Lakewood, Subframes, Caltracs





<font size=-1>[ This Message was edited by: dennis111 on 8/23/06 5:51am ]</font>
 

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you've still got to get at least 3 more tenths off of that 60 ft, that would probably get you in the 12 teens or twenties. Crap, I was scratching off consistent 1.82's on 225/60 street tires, I know you can do better than 2.0's on slicks. That mph sure does look good!

If I ever get through with this head swap, I have a feeling slicks will be my next purchase, I'm seriously looking at the Hoosier's like you have. They sure look good on those magnum 500's.

<font size=-1>[ This Message was edited by: indigo66 on 8/23/06 3:51am ]</font>
 

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Damn!! Your car must really come on strong after the 1000' mark because I'm running 5.236 at 330' 8.197 at the 660'@83mph and 10.786 at the 1000' mark and run 12.9'[email protected]
I don't get it....
 

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Discussion Starter · #4 ·
On 2006-08-22 13:01, 82GT wrote:
Damn!! Your car must really come on strong after the 1000' mark because I'm running 5.236 at 330' 8.197 at the 660'@83mph and 10.786 at the 1000' mark and run 12.9'[email protected]
I don't get it....
I checked the 3 good runs and have 10.630, 10.654, and a 10.721 1000'ers.

I don't know if it matters, but I do shift from 3rd (6200rpms) into 4th almost exactly at the 1000' mark. This gets puts me back to a little under 5000rpms which is at the beginning of the powerband of the engine. Goes through the traps about 5500rpm.

_________________
Dennis

65' STANG, 3160 lbs

393W NA, 2.78 Toploader 4 Spd, 9" 3:70 Posi
Pro Comp Heads, Vic Jr. Intake, 750dp, 236/561 Solid Cam, 9.6CR, 1 3/4" Headers, Lakewood, Subframes, Caltracs




<font size=-1>[ This Message was edited by: dennis111 on 8/23/06 4:35am ]</font>
 

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65' STANG, 3160 lbs

393W, 2.78 Toploader 4 Spd, 9" 3:70 Posi
Pro Comp Heads, Vic Jr. Intake, 750dp, 236/561 Solid Cam, 9.6CR, 1 3/4" Headers, Lakewood, Subframes, Caltracs
Something more fundamental seems wrong here. 3160 lbs at 114 with a 393?

Have you dynoed this combo? It seems like you're getting sub 300RWHP with this.

I would look for power in the carb, exhaust, timing.

Then regarding the traction -- what exactly is your rear suspension setup? Do you have the CalTracs installed?
Are you running a pinion snubber?


Hmmmmm.........
 

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Are you doing a proper burn out?
 

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Discussion Starter · #7 ·
On 2006-08-22 13:33, allenman85 wrote:

Something more fundamental seems wrong here. 3160 lbs at 114 with a 393?

Have you dynoed this combo? It seems like you're getting sub 300RWHP with this.

I would look for power in the carb, exhaust, timing.

Then regarding the traction -- what exactly is your rear suspension setup? Do you have the CalTracs installed?
Are you running a pinion snubber?


Hmmmmm.........
Do you really think there is much more? That is encouraging.


This is a street/strip car with only maybe 10% track time. It was never intended to be a full on strip car and great driveability is a must. My goal is not lofty, but I do intend to eventually cut a 12 second flat quarter, which is my IHRA track's limit for no roll bar.

The engine hasn't been dyno'ed, just street tuned with virtually no strip time. It has a a Biggs 750 Stage 5 dp, full 2 1/2" dual exhaust with dynomax mufflers and tailpipes, and I am running 35 degrees max timing at 3000rpm.

The Comp 282S cam is pretty small for a 393w and I consider this and the suspension as being the 2 weakest links.

I am fully aware that I need to work on the suspension. 2 second 60's are nothing to write home about. I certainly don't have anything to brag about and the 4 speed adds to my aggravation--although I wouldn't have it any other way.

I have the Caltracs installed, subframe connectors, new std rate leaf rear springs, and crappy gas-adjust shocks that don't allow the rear to drop like I want it too. Front suspension is stock with GT sway bar and the Shelby drop. Again, I have the gas-adjust shocks which I plan to replace. I plan on replacing all 4 shocks with Rancho 9000.

I haven't investigated a pinion snubber yet, but this is a rolling work in progress and I will check into it.

Tires must be DOT for my class and the Hoosier's come highly recommended. Although they get very, very sticky when hot, I still can't launch them at a very high RPM. I am sure that with full slicks plus the higher launch that it could run faster right away, but they are not consistent with my plans.

_________________
Dennis

65' STANG, 3160 lbs

393W NA, 2.78 Toploader 4 Spd, 9" 3:70 Posi
Pro Comp Heads, Vic Jr. Intake, 750dp, 236/561 Solid Cam, 9.6CR, 1 3/4" Headers, Lakewood, Subframes, Caltracs





<font size=-1>[ This Message was edited by: dennis111 on 8/23/06 5:30am ]</font>
 

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20psi is pretty high for qtp's in a 3100 lb car. I run 18 - 20 in my 4200 lb Gal and yes they bite like mad. I run 1.73 short times without tubes and have not noticed mine spinning on the rim. Spinning that much with those 60' times tells me something aint right. That said many people including myself believe letting it spin on the rim is ok as long as it's not excessive.Just watch that the tubes aint spinning also.
 

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i dont drag but tubes may push on the center of the tread and the low tire pressure might not let the tire seal to the rim well. all i know is when i get tires they are loose until air is put in. the tubes are for safety right?
 

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Hey Dennis you're running some decent times and having fun with the car,that's what counts. There is always someone who's going to be faster or slower with the same combo.

To keep the tires from spinning on the rim and ripping out the valve stem I'd just toss the tubes.The ET Streets on my Falcon have no tubes and don't have a problem running 15PSI at the track for some 1.6XX 60 foots. The 26x10x15 Hoosier slicks on the Morris are run tubeless also and are good for low 1.4xx 60 foots running 13PSI. You'll get better 60 foots with less PSI and a some practice launching the stick.
 

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I started out with the 26 X 15 X 9 or so QT Pros and they worked very well, but, as horsepower increased and tires wore down, traction (slight spin) became a problem. I bought a set of their xtra soft compound (not available in QT Pros) 26 X 15 X 10 slicks and they are unbelievable. I run through the water, haze them and immediately hit the line and they are good to go!

P.S. I ran both without tubes and found they worked well at 17 psi. By the way, at 113 mph you ought to be close to knocking high 11s. Your launch RPM is too low but beware because if you crank it up much higher, depending on your axle set up etc., you may be twisting the end off! I have the cal-tracs also. Are you in the bottom hole or upper hole in the front of the cal trac?

<font size=-1>[ This Message was edited by: 63SportsCoupe on 8/23/06 9:52am ]</font>
 

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Dennis -- the concept of the rear 'dropping' is backwards. Cars that plant force the axle down into the track. And you've heard "for every action there is an equal and opposite reaction" which means the body has to come up. Especially true on a leaf spring car -- you can see the fast cars 'separate'.

And yes -- you are leaving a lot of power on the table. A quick calc shows 361HP. That doesn't sound right, now does it for a 393?
I would expect 475 MIN and 525 for your combo.

You know the traction is limiting ET but it's not cutting into the MPH by much. That said check the following:
1) Is the carb opening 100% when you stand on it? Have a buddy check with you.
2) Is your timing pointer timed correctly? Did you check it mechanically?
3) Duals cost you 20 HP pk -- so uncorking would bump you 2 mph or so.
4) Where was the cam timed? Intake centerline....

You might not be fueling the motor enough or too much. Have you checked at the end of run? Check ALL plugs. Do you see evidence of detonation? (black specks on the porcelain).

I think you'll uncover the problem and start seeing 120MPH times!

Bill
 

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Discussion Starter · #13 ·
On 2006-08-22 16:17, FoMoCo wrote:
20psi is pretty high for qtp's in a 3100 lb car. I run 18 - 20 in my 4200 lb Gal and yes they bite like mad. I run 1.73 short times without tubes and have not noticed mine spinning on the rim. Spinning that much with those 60' times tells me something aint right. That said many people including myself believe letting it spin on the rim is ok as long as it's not excessive.Just watch that the tubes aint spinning also.
Hmm, interesting. I guess the tubes were a bad idea. In my case the tubes spun too.

With my first trip out on the tires, I wasn't trying to let too much air out thinking I would be safe. It took only a 3 runs to spin them. I've heard that they could probably be run as low as 14lbs if needed.

A lot of the tire spinning is, I believe, due to the fact that a 65/66 does not have a wide wheel well and tires need to be sized accordingly. They get overpowered from the bottom end torque. I am fortunate that I had rolled the wheel well flange plus I pushed the flairs out a little further when I innitially did the body work. Still, I only end up with about 8" of tread with the 26x9.50x15 Hoosiers.

Nice Galaxie, by the way!

_________________
Dennis

65' STANG, 3160 lbs

393W NA, 2.78 Toploader 4 Spd, 9" 3:70 Posi
Pro Comp Heads, Vic Jr. Intake, 750dp, 236/561 Solid Cam, 9.6CR, 1 3/4" Headers, Lakewood, Subframes, Caltracs



<font size=-1>[ This Message was edited by: dennis111 on 8/23/06 9:05pm ]</font>
 

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Discussion Starter · #14 ·
On 2006-08-22 17:10, trukstopcowboy wrote:
i dont drag but tubes may push on the center of the tread and the low tire pressure might not let the tire seal to the rim well. all i know is when i get tires they are loose until air is put in. the tubes are for safety right?
Good point about the tread center. Yes, it does look like the tubes might be pushing mostly on center, but wouldn't just plain air do the same thing? Isn't the pressure going to be equal?

I am running a 7" wide rim, which is within the recommended 6-8".

I put the tubes in for safety and to help keep the tires aired up over a longer duration.

_________________
Dennis

65' STANG, 3160 lbs

393W NA, 2.78 Toploader 4 Spd, 9" 3:70 Posi
Pro Comp Heads, Vic Jr. Intake, 750dp, 236/561 Solid Cam, 9.6CR, 1 3/4" Headers, Lakewood, Subframes, Caltracs



<font size=-1>[ This Message was edited by: dennis111 on 8/23/06 8:54pm ]</font>
 

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Discussion Starter · #15 ·
On 2006-08-22 18:40, 63SportsCoupe wrote:
I have the cal-tracs also. Are you in the bottom hole or upper hole in the front of the cal trac?

<font size=-1>[ This Message was edited by: 63SportsCoupe on 8/23/06 9:52am ]</font>
Currently at the top with zero preload (just touching) on both side. I think it might hit better on the bottom though. Any suggestions?
 

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Discussion Starter · #16 ·
On 2006-08-22 18:46, allenman85 wrote:
Dennis -- the concept of the rear 'dropping' is backwards. Cars that plant force the axle down into the track. And you've heard "for every action there is an equal and opposite reaction" which means the body has to come up. Especially true on a leaf spring car -- you can see the fast cars 'separate'.
I guess I don't understand the above paragraph and what you are trying to tell me. What i conclude from you statement is that I shouldn't try to plant the rear axle into the ground with drag shocks that allow the front to rise and the rear to drop during acceleration? Need clarification, please.

And yes -- you are leaving a lot of power on the table. A quick calc shows 361HP. That doesn't sound right, now does it for a 393?
I would expect 475 MIN and 525 for your combo.
Hmmm, I could only wish!
I have been under the impression that my current combo was good for maybe 400-420hp flywheel tops.

You know the traction is limiting ET but it's not cutting into the MPH by much. That said check the following:
1) Is the carb opening 100% when you stand on it? Have a buddy check with you.
2) Is your timing pointer timed correctly? Did you check it mechanically?
3) Duals cost you 20 HP pk -- so uncorking would bump you 2 mph or so.
4) Where was the cam timed? Intake centerline....
1. Yes, the carb is fully opening.
2. True TDC was determined when the engine was built and the stock cast timing pointer was modified to match. Initial is timing is 12 degrees.
3. Agreed.
4. Intake centerlilne is 106 and the cam was installed straight up. Lobes were verified during assembly.

We have a chassis dyno in the area. Perhaps when I can get the car hooking better I'll spend the $340 for a tuning session.

You might not be fueling the motor enough or too much. Have you checked at the end of run? Check ALL plugs. Do you see evidence of detonation? (black specks on the porcelain).

I think you'll uncover the problem and start seeing 120MPH times!

Bill
I've only pulled a couple of plugs and there is evidence of it being slightly rich. This something I need to do more research on.

Bill, I do thank you for your comments and insight. Every little bit helps to stimulate the gray matter.


_________________
Dennis

65' STANG, 3160 lbs

393W NA, 2.78 Toploader 4 Spd, 9" 3:70 Posi
Pro Comp Heads, Vic Jr. Intake, 750dp, 236/561 Solid Cam, 9.6CR, 1 3/4" Headers, Lakewood, Subframes, Caltracs



<font size=-1>[ This Message was edited by: dennis111 on 8/23/06 8:37pm ]</font>
 

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Discussion Starter · #17 ·
On 2006-08-22 18:04, Just Jim wrote:
Hey Dennis you're running some decent times and having fun with the car,that's what counts. There is always someone who's going to be faster or slower with the same combo.

To keep the tires from spinning on the rim and ripping out the valve stem I'd just toss the tubes.The ET Streets on my Falcon have no tubes and don't have a problem running 15PSI at the track for some 1.6XX 60 foots. The 26x10x15 Hoosier slicks on the Morris are run tubeless also and are good for low 1.4xx 60 foots running 13PSI. You'll get better 60 foots with less PSI and a some practice launching the stick.
Hey Jim, thanks for your input. It is all about having fun and to me, nothing is better than rowing the 4 speed! I am out to race myself, not the other guy. Of course I want to be faster, but that will take time and more experience.

I guess I really need to ditch the tubes. Glad to hear that others don't have problems running without them.

Yes, I certainly need a better 60' and that is where I want to focus. I need more traction. I suppose it certainly doesn't help my 60's shifting into second during it (@6200 rpms.)

Need traction, need traction, need traction, need traction. . . . .


_________________
Dennis

65' STANG, 3160 lbs

393W NA, 2.78 Toploader 4 Spd, 9" 3:70 Posi
Pro Comp Heads, Vic Jr. Intake, 750dp, 236/561 Solid Cam, 9.6CR, 1 3/4" Headers, Lakewood, Subframes, Caltracs



<font size=-1>[ This Message was edited by: dennis111 on 8/23/06 8:59pm ]</font>
 

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Have you noticed "bobbing" as you leave the line? I understand that running in the upper hole will initially plant rear harder/faster. The Ranchos or other adjustable "rebound" shocks are designed to slow the unloading process at least for a brief period of time but if you are on/off throttle (pedaling) as you leave because of traction, it may be causing loading/unloading condition. Being smooth on the throttle as you launch (with the adreneline pumping) is an art, but that's the wonderful thing about practicing. It might be worth trying in the lower hole for more consistent launch "feel".
 

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I agree to ditch the tubes. I don't use them either.

When I first read the title of the post I though you must have broken something. That's when I thought there was too much traction (or not strong enough parts).

You just made a huge improvement! Enjoy it!

<font size=-1>[ This Message was edited by: 289nate on 8/24/06 12:04am ]</font>
 

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Coat the insides of the tires with dish soap, keeps drag slicks from losing air when running tubeless, works really well!

Roger
 
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