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Discussion Starter #1
I am taking my Torino to Memphis Thursday for test and tune. Hoping to run low 14s- high 13s more so on the 13 side. I have a mild .040 429 [email protected] .50 .509 lift hydraulic, performer rpm w/ 750 dp, 1 5/8 shortys, harland sharp rolllers, C6 with a 3k stall and detroit locker 3.89 gears, my guess is the car is weighing around 3900-4k w/ driver it was about 3750 w/ me and the 351c. I can't get it off the line with out blowing the tires bad, I have a set of off brand 255/60/15 on the back but also have some goodyear DOT specials (thats whats on the tires bought them used) they have 8x 26.5 on them I threw them on this morinig and they make the car pretty squirelly off the line, I foot braked to about 2k ,but didnt heat them up either, should I burn out first? Any help would be greatly appreciated, I raced a guy in a 2k Mustang GT auto who said he ran a 14.0 a week ago and from a 25 punch I took him by 1- 1 1/2 cars, I did spin through first that was on my 255/60s

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87 Mustang GT 5spd 2.73 daily driver
70 Torino GT 429 C6 3.89
70 F100 360 C6 3.25L (in lots of pieces)

<font size=-1>[ This Message was edited by: MGT351 on 3/6/02 12:17am ]</font>
 

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Your car is front-heavy like all the older cars. Here are some of the things I woud consider depending on your desire to mod a classic:

1- sticky tires are a must
2- relocate battery to trunk
3- if your engine compartment is like mine, mount engine/trans back an inch or so
4- traction bars to stabilize the leaf springs
5- frame ties if the Torino is a unibody(more traction will add torque to the frame)
6- aluminum heads for front end weight reduction

etc...
 

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Discussion Starter #3
I do have traction bars, forgot to mention that, the sticky tires, the sticky tires make the car harder to control, anybody have any insight to this? the car does wheel hop on the 255/60s. Those are all good ideas, but I am going to track in 2 days so i kinda am stuck with what I have for now, just got the BB springs under the front other than that the car is stock suspension
 

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Was the air pressure the same on both sides?
 

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Discussion Starter #5
they were both 15psi, however the front was 17 on the driver side and 28 on the passanger. didnt catch that till after though.
 

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I would think that the DOT specials might be dried out.Thats why you are getting squirrly on the launch.You said the 255's give you wheel hop.that tells me you are getting better grip with them if they are twisting the rearend.a set of traction bars should fix this.I would do a couple of short burnouts b4 you goto the track to see what air presure gives you the best contact patch.if the patch is dark on the sides increase pressure if its too dark in the middle decrease pressure .you want an even patch of rubber all the way across.Dropping the air pressre too much with radials will cause cupping and youll lose traction.Also dont stay in the waterbox to long or the tires will get greasy.When I use radials I usually stay in th water only a few seconds then stay under power out of the box till I hear the tires screech.
Bob
 

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Use your sticky tires, and make sure the fronts are inflated to at least 35psi. Many folks, including me, put extra air in the fronts to decrease rolling resistance. (You ever try and pedal a bicycle with near flat tires?)


Do a burnout, and try it again... this time with air in the front tires!
Also remove all the dead weight out of the car... spare tire, jack, junk in the trunk, etc. Weight means as much as horsepower. Every 100lbs is worth around a tenth in most street cars. A cool engine also runs better.

Good Luck!
 

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It seems to me that you are under-cammed, considering that you have the RPM manifold, 3.89 gears and 3000 rpm stall. You probably have tractor-like torque at your stall speed which is creating major traction problems with the low axle gearing.

I'd be tempted to try something with at least 230-236 degrees of duration @.050". That would be a "rumpety-rump" cam with a small block, but should be more than mild and tractable with 429 cubes. This would kill a little bit of the excessive low-speed torque to get that heavy car moving, and more than make up for it with additional torque higher in the range, after the tires have hooked.

One limiting factor with this combo could be compression ratio; you'd need perhaps 9.5 to 1 for a strong street/strip combo with iron heads and this cam timing. If you have "smog" heads with big chambers and 8 or 8.5 to 1, this cam timing would kill net mean effective cylinder pressure (dynamic compression). As Mustangzrule suggested, then it would be aluminum heads (and 10-1 compression) time. Big money, but big performance and less front-end weight.

Both compression and budget on the low side? You might go quicker with taller axle gearing and the very conservative cam. Taller gearing would reduce the axle torque at launch, allowing you to hook, while letting you compensate for that initial lost axle torque by staying in the lower gears farther down the track. Average axle torque under the curve = total acceleration potential.

Only other limiting factor I see in the larger cam scenario is the 1-5/8" headers; a little small for the rest of the combo. Good luck!

Steve Amos
 

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Discussion Starter #9
The heads are DOVE-C, I have dished pistons, im guessing around 9.5 cr, they have stock valves with mild pocket porting, I removed the exhaust bump and port matched them, the intakes are ported to a CJ size only because the previous owner already had one head done this way. I ran this cam because it was the biggest i could get away with, without having the heads machined. This was to be a budget motor only have about 1500 in it, to get me by till my 466 roller motor is ready. I do have traction bars and I noticed the tread that I left @ 15psi looked like a outline only the outside is contacting. Should I run more pressure? I am running these tires on Explorer rims 15x7 they are Goodyear brand.
The front tires are 235/60/14 on 14x6 wheels.
_________________
87 Mustang GT 5spd 2.73 daily driver
70 Torino GT 429 C6 3.89
70 F100 360 C6 3.25L (in lots of pieces)

<font size=-1>[ This Message was edited by: MGT351 on 3/6/02 10:17am ]</font>
 

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If you are seeing a tread mark on the pavement that is dark only at the outside edges of its width, you are indeed under-inflated.

Gradually increase the tire pressures until you put down an even, black mark across the full width of the imprint. If it starts to get darker in the middle, you've gone too high with the pressure.

More rubber on the ground will definitely help you in this big-torque application.
 

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Try unhooking the front swaybar, should let the front end rise more, putting more weight on the rear tires.
Roger
 

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Don't get radials wet in the burnout box. The water will stay in the treads and actually lose you traction. Burnouts are for slicks and treadless types only.

Read that in an old issue of MM&FF...
 
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