I have a 86 305 tpi, auto with 2.73 (or 2.77, forget which it is). The inner pinion bearing is shot, howling,m and growling like a SOB, it's going to a rear end specialist to be rebuilt on Monday. My question is, should I do 3.XX, or should I spend the extra money and get a good cam in this thing. I been wanting to get the peanut cam outta it since I bought it. Which would be the most benificial to the performance? Thanks guys!

 

well, if youre having the rear rebuilt, u might as well put the gears in.. or else u have to pay again to unbutton the rear later on = that would be a waste of $.. do the rear, then get the cam..

 

Cam hands down. I'd get somethin along the lines of the comp xe256. Having owned an 86 with 3.23's in the past, I can tell you that that motor will be a pig no matter what gears you're turning with the stock cam in it.

 

yeah, but if he's getting his rear rebuilt. why wait for the gears that he will eventually need with the new cam?

 

lol...put it this way I spent $860.00 on my richmond 3.73 gear. I had a series 2 carrier, so I had to update to a series 3 carrier. So all the guts of my 10 bolt were swapped plus all new bearings and seals. I had 100,000 miles on my car why not redo everything while they were in there.
Biggest gear you can go with a series 2 is a 3.08 though. That wasn't a big enough jump from my stock 2.72 gear for me.

And if you have a 9 bolt borg-warner 7 3/4" .....save your money I heard those are more to rebuild. Plus the biggest you can go from what I found was a 3.73.
The 10 bolt you can go to a 4.56 if you wanted to.

I paid $230.00 just for my cam, but I recommend saving for some other things to if you plan on swapping a cam.
Timing gear & chain, AFPR, valve seals, injector o ring kit, fuel rail o ring kit, springs to match the cam, roller rockers, water pump maybe, ect. Just little things to do while your taking the upper part of the motor apart.
Both things are going to be $$$
but if your rear end is going....getting a bigger cam isn't going to fix that. LOL...if anything its going to make it worse because of the HP gain u will get from the cam.

 

I just put a 3:73 in place of my stock 2:73 in my 92 T.A 305 auto. Bought Summit thick gears($130), and a Summit instalation kit which includes all bearings, seals, and shims, crush sleave and so on($90), 2 quarts of Royal Purple diff. fluid($20), and a friend installed it for $175.
Best of all it took .8ths in the quarter! It was a huge difference. Now it spins the tires from a stand still through first gear, and barks second!
I would recommend the gear swap first mainly because it is not dedicated to a engine size. Personally i plan to swap for a 383 within a year or two, so im making my car fun to drive without putting a bunch of money into parts i cant reuse for the 383. Im sure most 305 owners plan on a engine swap someday. Good luck, have fun, and be safe!

 

The cam and the gear change will both be beneficial for improving performance, so it's not really an issue over which will be better. You should do both. But since the rear is going bad, the first thing you oughta do is pick up a ten bolt rear with 3.23 or better gears in it. The nine bolt rears are obsolete, and it's expensive and difficult to get new parts for them. Get a good ten bolt rear under the car, then start shopping for a good cam to replace the pathetic "peanut" cam.

 

lol, I know a new cam aint gonna fix that!! lol, I mant should i spend the extra 250 bucks to have the guy put a better gear in it, I think I'm gonna put that money towards the summit tpi cam they claim wakes up the 86 305 tpi by about 40 hp or so. Thanks for the input guys, I appriciate it.

 

i used a cam summit sold a while back i dont think they sell it anymore. but it was a 40 hp for your 305 tpi i think slp or jet made it came with cam lifters valve springs.but the 40 hp boost was combined with buying and running there chip also i already had a hypertech so i didnt get the chip well i didnt get that cam either the grind was the same as edlebrock 2102-perf dur @.50 is 204/214 lift .420/.442 so i got the edlebrock cam and z28 springs much cheaper. it really woke the stock 305 up i was suprised. i did a few other mods at the time but it ran really good and i am building the exact same motor now for a 86 ta daily driver that my cousin just got

 

Still sold. http://store.summitracing.com/partde...0&autoview=sku

Wonder how it will run with the stock prom??

Do you have the edlebrock p.n?? Thanks