Installed POSI...Car feels slower..why?
08-23-2013, 10:38 PM
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Installed POSI...Car feels slower..why?
Hey guys so just yesterday I installed a POSI rear end off a 4th gen...the gear ratio on it is 3.23...but now that its on there...I feel as if the car got slower...is it just more strain on my engine that it struggles to move both of the wheels....PS i have an LG4 engine w/ mods. So Im guessing that might be the culprit right there.
08-23-2013, 10:57 PM
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Re: Installed POSI...Car feels slower..why?
It was open differential with what I believe had 3.23 gears. Its kinda funny because b4 the car could easily burnout with the open differential rear end..and now it struggles to burnout both tires...
08-23-2013, 10:58 PM
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Re: Installed POSI...Car feels slower..why?
the rear end came off a 2001 WS6 automatic
08-23-2013, 11:21 PM
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Car: 86 Camaro
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Re: Installed POSI...Car feels slower..why?
it is trying to turn both tires- of course it's going to have to work harder to do it. that's the whole point of a positraction differential.. but burnouts are wasted energy, anyways- now that energy is being used to move the car instead of laying a single black streak on the pavement ...
08-23-2013, 11:49 PM
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Re: Installed POSI...Car feels slower..why?
Yea, you have more than doubled the traction, so it's not going to spin the tires as easy. I hope you put new tires on the rear when you swapped the rear end. If the tires don't have the same amount of tread then it will cause the differential to slip all the time while you are driving it and it can damage the differential. The air pressure also must be kept equal between the rear tires.
08-24-2013, 12:41 AM
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Car: 1991 Trans Am GTA
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Re: Installed POSI...Car feels slower..why?
you went from burning out one tire to burning out both. twice the work for the engine.
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08-24-2013, 07:20 AM
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Car: '86 Camaro, '94 Camaro, 3 others
Engine: LG4 ->L29, L32->LR4, L36, LG4, L31
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Re: Installed POSI...Car feels slower..why?
Yea, you have more than doubled the traction, so it's not going to spin the tires as easy. I hope you put new tires on the rear when you swapped the rear end. If the tires don't have the same amount of tread then it will cause the differential to slip all the time while you are driving it and it can damage the differential. The air pressure also must be kept equal between the rear tires.
08-24-2013, 07:41 PM
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Re: Installed POSI...Car feels slower..why?
ye so now I need to beedf up my engine more so that it can spin those two tires...or like everyone else says "drop a 350" Now my other problems is that my tires rub on my fendors.
08-24-2013, 11:07 PM
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Car: 86 Camaro
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Re: Installed POSI...Car feels slower..why?
either roll the fenders or get wheels with more backspacing.
09-01-2013, 10:06 PM
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Re: Installed POSI...Car feels slower..why?
alright guys this might sounds kinda dum....but how exactly do I do a burnout now since all of my 4 tires are braking now..I find it hard to get my rear tires to break loose if im holding the brakes...aka I have a manual transmission.
09-01-2013, 10:18 PM
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Re: Installed POSI...Car feels slower..why?
ye i know that but i want to hold still while im burning out..aka to show off...LOL
09-01-2013, 11:51 PM
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Re: Installed POSI...Car feels slower..why?
I just finished my swap today 3.08 open/drum>3.73 posi(auburn)/disc and left two very nice black lines on the test drive.(very tired stock L03)
How are you attempting to brake stand it(burnout)? I'm guessing your using the side-step method?
How are you attempting to brake stand it(burnout)? I'm guessing your using the side-step method?
09-02-2013, 08:28 PM
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Re: Installed POSI...Car feels slower..why?
yes thats the moethod im attempting to use unless you got something more effective?
09-02-2013, 09:11 PM
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Car: 92 Camaro RS
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Re: Installed POSI...Car feels slower..why?
My 92 is a LO3, t5, 3:42 posi,drum and burnouts have never been a problem (except with drag radials, those were some hard launches). Tires are 255/50r16. Rev it up and dump or slip the clutch. if you want to do brake stands, try reving it up, dump the clutch then move to the brake. It's worked for me.
Back in the day it was always fun blowing away all the 3:08 open rear cars, and being able to take some 5.0's down with a LO3.
Back in the day it was always fun blowing away all the 3:08 open rear cars, and being able to take some 5.0's down with a LO3.
05-13-2014, 11:31 PM
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Car: 86 Corvette, 89 IROC, 1999 TA
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Re: Installed POSI...Car feels slower..why?
That's what line locks are for, install line locks, flip a switch that locks only the front brakes and drop the clutch :P
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