Front to rear gear ratios for pulling competition.

I have a question for disturbed. I am running 4.11's in the front. If I run 4.56's in the rear according to my calculations that would be 10%. Would I be ok at that or is that to much.
 
Rustin said:
So, can you go back to the front end chatter problem?
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if you Over gear a Cepeck whether it is on the front or the back it will cause the truck to lunge from the tire turning faster than what the ground speed is. Its from the very aggressive tread. When the front is over driven to much it can cause the front to dance/chatter. When you run to fast a gear in the transfer case it can cause the truck to lunge. If you have ever seen someone try and wind the engine up and dump the clutch with cepeks on you would see daylight under the entire truck. Wheel speed to ground speed is very touchy with them in a 4wd setup. That's why most ride the clutch out before cutting the tires loose.

mcmullentrucks said:
I have a question for disturbed. I am running 4.11's in the front. If I run 4.56's in the rear according to my calculations that would be 10%. Would I be ok at that or is that to much.
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I've never tried 10% but some have I'm sure
 
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I'm sorry, my engineering manuals never covered a "Cepeck". It sounds like you don't know what you're talking about. Please only discuss terms that my training covered so that I can make informed snide comments on them.

DISTURBED said:
if you Over gear a Cepeck whether it is on the front or the back it will cause the truck to lunge from the tire turning faster than what the ground speed is. Its from the very aggressive tread. When the front is over driven to much it can cause the front to dance/chatter. When you run to fast a gear in the transfer case it can cause the truck to lunge. If you have ever seen someone try and wind the engine up and dump the clutch with cepeks on you would see daylight under the entire truck. Wheel speed to ground speed is very touchy with them in a 4wd setup. That's why most ride the clutch out before cutting the tires loose.



I've never tried 10% but some have I'm sure
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Cepeck Technical reference

HPIM3997.jpg

Overall Diameter: 34.1"
Overall Width: 18.1"
Ply Rating: 4 ply Tubeless
Rim Width: 18" to 22"
Tread Depth: 20/32
Lugs per Side: 30
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Aggressive.
 
that has nothing to do with the tire :) that all in the dirt of the day. Its clay content, moisture, dirt percentage, what minerals are in it. very tech stuff.:Cheer:
 
DirtyMaxx03 said:
This amazes me lol

I am no sled puller at all but damn it man, if something is proven and has been for 40 years don't argue it. Sometimes things don't work the same way in real life as they do when calculated out on a sheet of paper.
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Really, so back in the 70's and thru the early 2000's everyone set up drag cars the same.

No one believed in sway bars to help and no one set motors down and pointed the front down.

So in the 70's when i explained that and everyone did just kinda similar to whats going on here... "kid this is how it's done", no other reasoning EXCEPT "been doing it 30 yrs like this, it works" well they did it WRONG for another 30 yrs, combined doing it wrong for damn near 60 years...

Now everyone is doing what i was doing then.

Just because its being done doesn't make it all right.

.
 
Supershafts said:
Really, so back in the 70's and thru the early 2000's everyone set up drag cars the same.

No one believed in sway bars to help and no one set motors down and pointed the front down.

So in the 70's when i explained that and everyone did just kinda similar to whats going on here... "kid this is how it's done", no other reasoning EXCEPT "been doing it 30 yrs like this, it works" well they did it WRONG for another 30 yrs, combined doing it wrong for damn near 60 years...

Now everyone is doing what i was doing then.

Just because its being done doesn't make it all right.

.
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Is your name Greg Hogue?

So you single handedly change drag racing to what it is today? I mean the multimillion dollar drag teams didn't know all this but some kid from new York did? I find that hard to believe. You were drag racing in the 70's?

I'm still waiting to hear how many 4wd drive programs you have been involved in.
 
Supershafts said:
Really, so back in the 70's and thru the early 2000's everyone set up drag cars the same.

No one believed in sway bars to help and no one set motors down and pointed the front down.

So in the 70's when i explained that and everyone did just kinda similar to whats going on here... "kid this is how it's done", no other reasoning EXCEPT "been doing it 30 yrs like this, it works" well they did it WRONG for another 30 yrs, combined doing it wrong for damn near 60 years...

Now everyone is doing what i was doing then.

Just because its being done doesn't make it all right.

.
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Ok, Show some proof! Till then get that link in your signature fixed!

Because I see this
ScreenShot2014-03-17at105533AM_zps0765fc9d.png


When it is really this!
ScreenShot2014-03-17at105521AM_zps3955bddc.png


I can't respect that.
So, show some proof of your labor and let the truth make you free. Till then your not being a positive contributor to this thread.
 
When you air down the front tires how much height does the tire lose? for example a normal 33" tall tire that holds a max air pressure of 65 when deflated to 25 what is the new height of the tire?

I would measure this on my truck but its currently in more than one piece
 
Depends on what the weight box weighs. Will be different on every truck. what I can get away with on my truck, somebody else may not be able to because of the different configurations
 
DISTURBED said:
Depends on what the weight box weighs. Will be different on every truck. what I can get away with on my truck, somebody else may not be able to because of the different configurations
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Exactly. Same is true of a BFG vs STS vs XYZ. As I'm sure many know, not all 33" tires are 33". You also can't just go by what the company website says, sometimes you have to run a tape measure around the outside circumference and do trig, or maybe it was geometry? LOL Also have to take into account once the tire is mounted and what rim width, which also affects the height.
 
94 12valve said:
When you air down the front tires how much height does the tire lose? for example a normal 33" tall tire that holds a max air pressure of 65 when deflated to 25 what is the new height of the tire?

I would measure this on my truck but its currently in more than one piece
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Why do you want to know how much shorter the tires are when you deflate them down to 25 psi? You realize if you bag the tires down on the front with low air pressure and weight on them that measurement from the ground up won't give you a accurate number for a wheel speed calculation.
 
Something i remember seeing back when i was a tot with ear muffs and a su-su....

Do competitors have people come out and take a look at the front/rear tread dig patterns as the truck pulls ahead and the sled moves back to make sure they are getting a good dig pattern on all 4 corners?
 
Nootch said:
Something i remember seeing back when i was a tot with ear muffs and a su-su....

Do competitors have people come out and take a look at the front/rear tread dig patterns as the truck pulls ahead and the sled moves back to make sure they are getting a good dig pattern on all 4 corners?
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That might be unsafe.
 
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