I was thinking about changing to a 12 bolt.What made you guys do it.I'm a little worried about adding some serious mods because of the rearend,I don't want to dig myself in a ditch because I have to spend the 2 grand on the rearend after I bought a (no specific order) TC,cam,heads,draglites and most likely slicks.What order should I go about doing this.

 

Get a 9"

 

agreed

 

http://www.moserengineering.com

Call them and start asking questions.

 

"Bulletproofing" the car is the only way to minimize breakage on your road to horsepower. However, you have more time wth your auto. Get a driveshaft/12bolt/converter/tires, then beat the poop out of your car - and enjoy it!

Looking at the history of autos at the track, you are probably safe until you hit the track with ET streets or better.

Ryan

 

since u are an auto guy, i would not be too worried at this point. i have seen many auto LT1 guys run low 12's on the stock rear end with like 1.6 60' times. dont worry about it yet. mabey invest after u start running mid to low 12's but for now, u are fine.

 

My original rear has held up very well so far. I just got back from a day of testing and a new best 1.49 60' time. I will be switching from that to a Strange Eng 12 bolt as soon as it arrives, any day now actually. /My reason for changing has more to do with my going from a 28" bias slick to a 30" radial slick. The taller slick needs a 5.13 gear instead of the 4.56 the 7-1/2" one has now.
Of course the extra strength is an added bonus!

 

What kind of mods do you have and what horsepower do you produce,so you had no problems running slicks on a stock rearend.I was thinking a cam or tc first,but in what order should I do it.I will probably go with a hotcam cause of emissions I want to go bigger but I don't want to fail,and a 3200 stall tc.

 

I started from the rear and worked my way forward on my car.

Moser 12-bolt & driveshaft, then TH400 and 383. If you get a big converter, you'll break the stock rear. Seemed like common sense to me.

 

I run an ATI 8" conv w/ 5k stall. My normal bracket motor is a 400 with a Comp Cam 294s cam, Victor jr intake, and Reworked set of 461 heads among other things. It isn't real exotic, the combo just works. Both front and rear suspensions have been have set up for max wt transfer and seem to work ok. I made some changes to it over the winter to address some launch issues and soften the hit on the tires somewhat, it liked to spin at times. /i did put it on a chassis dyno just to see what it had and it showed 343 at the rear wheels, not a huge amount but it makes plenty of torque. The tranny has also received a 2.75 low gear set. In early preseason testing, it appears the spinning issue has been rectified. As I said, I am going to a taller tire that needs more rear gear and choices for the little dif are pretty limited. One thing I did do to help the rear live longer was to add the reinforced cover, it did stop the usual cap movement in mine.
As far as what's been done to the 305 motor goes, that isn't info that will ever be put out for general discussion.
I would do the cam and converter and then see what it does. Likely you will find it'll want more rear gear and get the set that goes with the largest tire you can run. The 4.56 is good with a 10.5 x 28 ET Drags.

 

Run what you have until it breaks, then consider upgrading to a 12 bolt or 9".

I swapped out my 10 bolt to a 9" when I finally installed a transbrake in the car. I didn't thing the 10 bolt would take more than one hit off the transbrake.