Will the 12bolt live?
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From: Central,NJ
Will the 12bolt live? Hey guys, couple questions. Will a spooled 33spline 12bolt with a 4.30 street gear live behind a TH400(2.75 1st) leaving off the transbrake, 4k stall, 3600lbs 360-400rwhp?
How many passes should I expect before I R&R the ring&pinion?
Is a 9in worth it at this point?
How many passes should I expect before I R&R the ring&pinion?
Is a 9in worth it at this point?
Last edited by Kevin97ss; Oct 20, 2009 at 05:50 AM.
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From: Central,NJ
Sounds good,... reason I ask is the R&P in my current 12 bolt looks quite worn with somewhere around 30 passes and 2k miles, this was with the stick and current set up(see sig) launching off the 2 step. I figured I would freshen it up and sell it then build a new narrowed rear.
With serious bracket racing in mind I want it reliable so the 9in is also "on the table". Just trying to decide.
With serious bracket racing in mind I want it reliable so the 9in is also "on the table". Just trying to decide.
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From: Central,NJ
Thread Starter
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From: Central,NJ
Do you have any fitment issues with the 9in? Seems to be my biggest hang up besides the additional power loss. I dont want to any irreversable chassis mods, beating in the tunnel etc.
Tq arm will probably put a dent in the tunnel, they have on every car I've seen to date, doesn't matter if you go 12 bolt, 9 inch, s60, they all generally need a little more clearnace.
not a big deal, you can't see it from inside the car. If you have the car lowered, it will be worse though, that I can tell you. As soon as I lowered mine, it re-clearanced itself after about 2 passes at the track
Not alot, but when I go under the car and nut/bolt it after every track trip, I can tell if the rear was set too soft if there's any additional mark Just part of putting a stronger/bigger rear in these cars, it's unavoidable for the most part.
not a big deal, you can't see it from inside the car. If you have the car lowered, it will be worse though, that I can tell you. As soon as I lowered mine, it re-clearanced itself after about 2 passes at the track
Not alot, but when I go under the car and nut/bolt it after every track trip, I can tell if the rear was set too soft if there's any additional mark
Just part of putting a stronger/bigger rear in these cars, it's unavoidable for the most part. 
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From: Central,NJ
Tq arm will probably put a dent in the tunnel, they have on every car I've seen to date, doesn't matter if you go 12 bolt, 9 inch, s60, they all generally need a little more clearnace.
not a big deal, you can't see it from inside the car. If you have the car lowered, it will be worse though, that I can tell you. As soon as I lowered mine, it re-clearanced itself after about 2 passes at the track
Not alot, but when I go under the car and nut/bolt it after every track trip, I can tell if the rear was set too soft if there's any additional mark Just part of putting a stronger/bigger rear in these cars, it's unavoidable for the most part.
not a big deal, you can't see it from inside the car. If you have the car lowered, it will be worse though, that I can tell you. As soon as I lowered mine, it re-clearanced itself after about 2 passes at the track
Not alot, but when I go under the car and nut/bolt it after every track trip, I can tell if the rear was set too soft if there's any additional mark
Just part of putting a stronger/bigger rear in these cars, it's unavoidable for the most part.
Check out the above Formula with a Moser 12 bolt and a Spohn torque arm, no clearance problems. Bob
The bracket that attaches to the rear on my BMR tq arm hit.
I have the back of the car lowered about an inch, and depending on track conditions, I will sometimes have the shocks somewhat soft (some of these new england tracks and prep, aren't really friends, that and when it's cold out and there's no heat in the track sometimes ya have to soften the car up some to get it to hook).
It hit, when I had the rear shocks on 4, when I have had them on 5 to 8 the arm never really hit.
The mark it left isn't big, about 1/3 of a dollar bill if that makes sense.
I have the back of the car lowered about an inch, and depending on track conditions, I will sometimes have the shocks somewhat soft (some of these new england tracks and prep, aren't really friends, that and when it's cold out and there's no heat in the track sometimes ya have to soften the car up some to get it to hook).
It hit, when I had the rear shocks on 4, when I have had them on 5 to 8 the arm never really hit.
The mark it left isn't big, about 1/3 of a dollar bill if that makes sense.
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From: Central,NJ
http://www.exoticperformanceplus.com...tCar.php?car=7
Check out the above Formula with a Moser 12 bolt and a Spohn torque arm, no clearance problems. Bob
Check out the above Formula with a Moser 12 bolt and a Spohn torque arm, no clearance problems. Bob
I am doing a different but similar build(NA,drag radial) for "street car" bracket racing and possibly an 11.50 index class. I intend to drive the car to the track (8 miles each way) and have it pass NJ state insp :o
Last edited by Kevin97ss; Oct 21, 2009 at 08:21 PM.
Thread Starter
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From: Central,NJ
The bracket that attaches to the rear on my BMR tq arm hit.
I have the back of the car lowered about an inch, and depending on track conditions, I will sometimes have the shocks somewhat soft (some of these new england tracks and prep, aren't really friends, that and when it's cold out and there's no heat in the track sometimes ya have to soften the car up some to get it to hook).
It hit, when I had the rear shocks on 4, when I have had them on 5 to 8 the arm never really hit.
The mark it left isn't big, about 1/3 of a dollar bill if that makes sense.
I have the back of the car lowered about an inch, and depending on track conditions, I will sometimes have the shocks somewhat soft (some of these new england tracks and prep, aren't really friends, that and when it's cold out and there's no heat in the track sometimes ya have to soften the car up some to get it to hook).
It hit, when I had the rear shocks on 4, when I have had them on 5 to 8 the arm never really hit.
The mark it left isn't big, about 1/3 of a dollar bill if that makes sense.
Are your jounce bumpers still intact?
Yes it's the top portion of the bracket that hits.
I took the bumpstops off the car because I was having a problem with the car unloading when it hit them a couple years back, I never tried putting them back on, but I can't see that helping anything so I left them off.
It hit a little even when they were on fwiw, definitely hit more after then came off, at least for a couple passes anyway
I took the bumpstops off the car because I was having a problem with the car unloading when it hit them a couple years back, I never tried putting them back on, but I can't see that helping anything so I left them off.
It hit a little even when they were on fwiw, definitely hit more after then came off, at least for a couple passes anyway
no hitting issues with my 12 and BMR ta here and the car over 1.5 lowered. you have to use the inner holes.
I have seen that 12 go 8's with no issues.
now, if it was a 6 speed you would have problems.
I have seen that 12 go 8's with no issues.
now, if it was a 6 speed you would have problems.