I'm in the Santa Rosa area, about 1.5 hour north of San Francisco, up hwy 101. I'm slowly exchanging out my worn factory drivetrain for sturdier newer parts. My engine builder wants me to ditch my 9 bolt Borg for a Ford 9-inch, but I just don't have the money to replace everything on the car all at once.

What I've got is the factory 88 IROC 9-bolt with the posi 2.77 highway gears. I don't need some 4.11 drag strip set up, as I like to do a lot of cross country interstate travel. Anyone have a 3.something posi 9-bolt they'd care to sell?

Also, I'm starting a search for a healthy replacement 700R4 that's been designed for a torque monster engine- It must have documentation of the work and parts used, and if used, an idea of the mileage on it.

Thanks, and keep those Radar Detector's dialed up! Nitro

 

i wouldnt bother with the 9bolt parts are hard to find i have one i will be getting rid of but will be awhile. Id stick with what you got until you save the cash for 9inch or moser 12 bolt rear. If its not going to be a drag racer dont worry about the gears they will help you on a trip. Now if you interested i have a 700r4 im selling but it needs rebuild. I have a guy interested right now but may not sale. Might be able to find pretty much a 700r4 shale and build it up yourself cheaper than buying one already built.

 

Our brother from SW Virginia is essentially correct (used to live in Fluvanna Co. here). Replacement parts for the 9 bolt are hard to get. The gearing is very attractive however. I would recommend you find a 4th gen rear at 3.42 or maybe even something at 3.27. The 9 bolt rear at 3.23 would be cool and those are parts you can find. I think you can got up to 3.08 in the rear you have now but if it ain't posi, ditch it. If it's drums, don't think twice.

Did I just type that?

 

if you dont want to use your stock wheels a 4thgen rear would be good. All 9bolts are posi and all have disc brakes. they came with 2.77 3.27 and 3.40something. You can get those ratio's and on up to 4 something aftermarket 3.73 is a good gear. 10 bolts had the 3.08's and 3.23's. If you use 4thgen rear with stock wheels they will stick out of the wheel wells by 1inch doesnt look right. The 4thgen wheels or after market wont stick out tho. The 4thgen rear isnt as strong as the 9bolt is the down side if you want a rear just save and get the 9inch or 12bolt get the gear you want with posi or locker. 9bolt parts are expensive and hard to find or i would say stick with it. I have the 3.27 rear gear so im good to go until i build my other motor which will snap it like a twig. my T/A has the 2.77 gear 9bolt now after i swapped from car to car. Your car your choice but id go with the stronger rear verses the 4thgen. If your rearend is rusty better get some pipes out to help turn those torque arm and control arm bolts they will rust solid.

 

9 bolts also came in 3.08 for carburated g92 cars i believe it is still a 3 series carrier i have one in my garage.

 

my 85 T/A is carbed came with the 3.27 that i swapped to my iroc. Ive never heard of a 3.08 in a 9bolt only the 10bolt.

 

I don't know how long I have had plans to get new gears... One day maybe. If I could find a posi rear with disks and 3.08, I'd probably jump on it. Other than that, I'll wait for a deal on one with 3.27 or maybe even 3.42. It's going to have to wait though in any case...

 

Thanks guys for your thoughts and suggestions. I keep seeing used 9 bolts on our 3rd Gen website 'Classifieds' for sale, so I was hoping someone within driving distance might have one ready to sell: Sometimes you never know.

I wish I could afford a 9 inch or a Mosser (sp?), but this car suck the repair fund dry pretty regularly. Right now I'm slowly amassing parts to build up a ZZ4 block into a torque heavy power touring rod; damn those part prices add up quick!

I keep taking my wife's G35 out to Infinion Raceway's Wed night drags each month while the IROC gets some badly needed beaver bitch slap medicine, but don't know how much longer she'll put up with it!! (the wife)....

Just keep me in mind if any of you run across something! Thanks again, Nitro

 

i have a 700r4 rebuilt to hangle 400HP with about 20,000 on it. after the rebuild i installed a Transgo Shift kit with corvette servo from probuilt($160). Nice part throttle shifts, Firm WOT shifts. i also have the convertor that went with the transmission, unknown stall speed, a little higher than stock though. PM if interested.

Located in Bakersfield, California

 

Do you by any chance have any of the documentation on it?? And would you know any of the build characteristics for the converter??? Thanks for responding. I'll be out most of the next three days but will try to check back on the board at night. Bakersfield.... I spent a year at BSU- great campus. Plus my oldest friend grew up in Oildale. Have you lived there long??? Nitro

 

i dont know what happened to the paperwork on the rebuild. its been a couple of years since it was done. plus i didnt know as much about transmissions as i do now or i would have rebuilt it myself, so the guy told me he can make it handle 400HP, so i said ok do it. and he did, i knew how to do the transgo shift kit so i did that myself, i have the paper work on the shift kit though. as for the torque convertor, im not sure about it, i will look at the markings on it in a day or so and post back about it. i've lived in bakersfield for 23 years now, since i was a lil tike.