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 Post Posted: Wed Nov 12, 2008 7:44 pm 
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Scott Smith wrote:
I forgot to tell ya I need the Center to center length of the bottom bar too.




Forgot to put that in there ](*,)  ](*,)  It was tough to measure but looks like 20 1/2 long

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 Post Posted: Wed Nov 12, 2008 7:50 pm 
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Beretta wrote:
Scott Smith wrote:
I forgot to tell ya I need the Center to center length of the bottom bar too.




Forgot to put that in there ](*,)  ](*,)  It was tough to measure but looks like 20 1/2 long


Then what I posted should be good.

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 Post Posted: Wed Nov 12, 2008 7:50 pm 
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gearhead1011 wrote:
Beretta wrote:
I got the #s...It was not easy but here they are..
The lower bar is 4* down in front so that looks Ok right???

The front lower bar is 6 1/2" from the ground and the upper is 14 3/8
The rear lower bar is 7 3/8 from the ground and the upper is 20 7/8

So what does that tell you??????????

Im going to plot O:) it out my self and see what it comes out to


Assuming your bars are close to the length of mine (20.75") I get an IC of 51.8" out and 5.3" high. Sounds like a good place to start. I had mine at 49.6" X 5.7" but moved it out to 56.5" earlier this year to take some of the wheelie out of it.



Wheelie!!! That is just it It does not even pick the front wheel off the ground at all....

So should I leave it or move it back up one hole???

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 Post Posted: Thu Nov 13, 2008 8:26 am 
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Beretta wrote:
Wheelie!!! That is just it It does not even pick the front wheel off the ground at all....

So should I leave it or move it back up one hole???


I don't know if moving it up 1 hole will help. It looks like it's just not getting the weight on the back tires. I was looking at some of the other stuff on the logfile you sent me and it looks like your launching at 4000 rpm and the driveshaft speed is slow coming up. I'm not much on convertors and automatics but could it be it wants more launch rpm or could the stall be wrong for your combo.  Sometimes if your not applying enough power on the launch the chassis just won't work. When I had the Pinto I kept the little motor for a spare after I built the fast motor. I wounded the good motor and slapped the little one back in it to finish up the race season. The car didn't work worth a crap.  I figured the suspension settings for a more powerful motor would work fine with a lower HP motor but it wouldn't. The setup was all wrong. By the time I found the right settings we were about finished racing. I took the little motor out and sold it :-$ . I know you're building a different motor and was just wondering if the rest of your set up isn't more closely matched to what you're going go?

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 Post Posted: Thu Nov 13, 2008 9:09 am 
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Chuck I just kind of removed the motor and trans from the Vega when I sold it and put it right in the Beretta....the Beretta is 250lbs lighter that the vega was and the only other difference is the tire size and the rear gear.

Vega, 456 gear and 14x32 tire
Beretta 4.30 gear and 16x33 tire


I had the 456 gear in the Beretta but rpm was 74+ at the finish line so got a 4.30 gear and 71 hundred now.... :-k

What are you other guys with glides seeing at launch???

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 Post Posted: Thu Nov 13, 2008 10:59 am 
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Beretta wrote:
Chuck I just kind of removed the motor and trans from the Vega when I sold it and put it right in the Beretta....the Beretta is 250lbs lighter that the vega was and the only other difference is the tire size and the rear gear.

Vega, 456 gear and 14x32 tire
Beretta 4.30 gear and 16x33 tire


I had the 456 gear in the Beretta but rpm was 74+ at the finish line so got a 4.30 gear and 71 hundred now.... :-k

What are you other guys with glides seeing at launch???


Like I said I'm not much on the auto stuff but it sounds like there may be something to this.  You went to a lighter car that is geared higher,  not only the ring & pinion but the taller tire raises the ratio.  

I did the same thing as you did Barry. I took the motor & trans out of the Pinto and but it in a lighter,  higher geared car BUT a clutch works a lot different than a convertor.  I did find that the same clutch set up I ran in the Pinto and could get a full season out of didn't fair so well in the Probe. The 1st year out with the Probe I went through my spares and had extra built. I think 4 of them altogether.

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 Post Posted: Thu Nov 13, 2008 12:37 pm 
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Barry, don't think it'll be much help but heres the last two runs and they are the first 2 as far as logging driveshaft goes.

first run is on six cylinders and was just really a drive through.. (10.1 @138)
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Second one was a bit harder but there was no grip at all. (9.1 @ 148)

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 Post Posted: Thu Nov 13, 2008 12:49 pm 
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PS that converter is sposed to stall at around 5800 but there again I have not hit the throttle hard yet.

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 Post Posted: Thu Nov 13, 2008 4:21 pm 
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Barry, the instant centers have very little to do with weight transfer to the rear. It is determined by center of gravity location and the amount of forward force at the contact patch.  The higher powered cars like lower and forward COG, lower powered cars like higher and rearward COGs. The IC will only have primary effect at instant of launch. It can create more or less contact pressure at that time, but when you do that you can set yourself up for oscillation in that contact pressure as a secondary effect, that is usually addressed with spring/shock settings. The ideal is to set COG hight to match traction and power and set IC very close to neutral. There is always a balance between COG-Power-Traction.  There are a lot of things that influence those three things. First
Weight. For our purposes there are 4 kinds of weight. Weight that is forward is only weight you have to transfer. Weight that is rearward is weight you don't have to transfer. Weight that is low is weight that is hard to transfer. Weight that is high is weight that is easy to transfer. These weights can be exchanged for each other Depending on limitations of moving weight. Forward weight can be exchanged for low weight. Rear ward weight can be exchanged for high weight, to get your balance for your car. All cars are different in weight, power and traction, so one size does not fit all.
Traction speaks for it's self. Good tires of right size and enough pressure on contact patch and not over powered equals traction.
Power is not only dependent on your engine, but how much stored energy your engine has,(centrifugal weight of turning parts) how much gear you have, Higher gear(lower numerical) cut power. Then engine RPM as it relates to your torque curve. A little under and you could be applying less power than you think and a little over too much.
As I have seen the pictures of your car when you was building it, I would say your COG is pretty low and possibly a bit forward, maybe too low for the power you have now. There are a few thing you can do to get balance. The one we all like is more engine. the others are lower gear if trap RPM allows. Higher stall to get farther into torque curve or raise weight.

More engine costs money. New gear costs money. Torque converters cost money. Moving weight don't cost a lot but is labor intensive. So an easy way to test this is to add some weight to the right spot. I would suggest a temporary weight of just 50lbs securely, very securely attached to roll bar centered behind head and watch 60s and weight transfer. If it works you can raise engine or fuel tank, batteries ect or other things mentioned in off season.

Once you get the balance close all the other parts such as 4 link, shocks, springs even converters to some extent have less to do and that makes them much more effective.

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 Post Posted: Fri Nov 14, 2008 12:59 pm 
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Thanks Dennis.....

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