07-16-2018, 09:09 PM | #1 |
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Location: Central illinois
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Posi or not?
I have 3.08 rear gear in my 69 c10.
I want to go to 3.42. Do any of you not go to a posi rear end when you change gears? If so, did you regret it? |
07-16-2018, 09:13 PM | #2 |
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Join Date: May 2015
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Re: Posi or not?
I would ad the posi if it were mine.....but 3.42 is not much difference than 3.08....will depend a lot on your final trans gear and tire size...use a gear ratio calculator to determine your best options....http://www.csgnetwork.com/multirpmcalc.html
In your other post your talking about a ls/od trans swap.....a 3.73 or so will be much better with the od
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07-17-2018, 11:32 PM | #3 |
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Re: Posi or not?
Posi is fun and handy offroad. If you are getting inside the pumpkin for any reason, you might as well add it.
Only reason not to add is expense. Or if you're building a truck for a retired schoolmarm.
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07-19-2018, 07:31 PM | #4 |
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Location: Paradise TX USA
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Re: Posi or not?
It depends on what you want to do with the truck.
for most normal driving conditions, a posi is not needed. If you want to burn rubber with both tires, then install a posi.
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07-19-2018, 07:55 PM | #5 |
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Re: Posi or not?
The one negative with a posi is that if you are in snow or ice, and your right foot gets really into it, the back end can come around more quickly and get you sideways.
But if you're careful with your foot it will be ok and better at keeping you going rather than being stuck with one wheel drive.
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07-20-2018, 11:36 AM | #6 | |
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Re: Posi or not?
Quote:
-klb
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67 C10 fleet fuel injected '70 402, 700r4, 3.73 posi 07 335 sport turbo 6sp 94 Trans Am GT LT1 6sp posi -- sold after 22yrs 99 540 sport V8 6sp -- sold 73 240z L24 4sp -- given to friend 68 C10 step 350/350 3.73 open -- sold |
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07-20-2018, 12:06 PM | #7 |
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Re: Posi or not?
"The one negative with a posi is that if you are in snow or ice, and your right foot gets really into it, the back end can come around more quickly and get you sideways."
Is there any other reason for having a posi ? |
07-20-2018, 12:11 PM | #8 |
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Location: Orem, Utah
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Re: Posi or not?
Yeah, it lets you wear out your rear tires more evenly.
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07-20-2018, 06:48 PM | #9 |
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Location: Austin, TX, USA
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Re: Posi or not?
3.42 are a 10% gear increase which really isn't enough to justify the expense IMO. 3.73 are a 21% change making it much more worthwhile, once again, IMO.
Not adding the limited slip would be a mistake (again, IMO!). I have a long bed 71 GMC that I used to drag my boat around the yard with and I added a posi and gears to it that were from my Jimmy's old 12 bolt. The added torque of the 4.11 really help and without the posi, it would get stuck in the yard sometimes! Everything I own has a traction device of some kind except my '03 BMW. It's only a $4000 car and it costs $2500 to add the LSD! I'm way too cheap for that...
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44 Willys MB 52 M38A1 64 Corvette Coupe 68 Camaro 'vert LT1 & TH700 69 Z/28 355 12.6's @110 69 Chevy Short Step 4 1/2"/7" drop 72 Jimmy 4WD 4spd 4" & 35's 02 GMC 2500HD 4x4 Duramax |
07-20-2018, 08:17 PM | #10 | |
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Re: Posi or not?
Quote:
-klb
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67 C10 fleet fuel injected '70 402, 700r4, 3.73 posi 07 335 sport turbo 6sp 94 Trans Am GT LT1 6sp posi -- sold after 22yrs 99 540 sport V8 6sp -- sold 73 240z L24 4sp -- given to friend 68 C10 step 350/350 3.73 open -- sold |
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07-21-2018, 07:55 PM | #11 |
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Join Date: Dec 1999
Location: Austin, TX, USA
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Re: Posi or not?
LOL. That was true of the IRS in my 240z as well, but the car was way more fun to drive when I swapped a Precision Gear clutch type LSD in it. Wish the beemer one wasn't so stupid expensive...
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44 Willys MB 52 M38A1 64 Corvette Coupe 68 Camaro 'vert LT1 & TH700 69 Z/28 355 12.6's @110 69 Chevy Short Step 4 1/2"/7" drop 72 Jimmy 4WD 4spd 4" & 35's 02 GMC 2500HD 4x4 Duramax |
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