Oldsmobile 307 upgrades

[spidereyes455]

If your engine has 5A heads on it already then it is not a roller motor unless someone changed them. which makes it a better starting point for modification. as for the rear unless you can find a build sheet somewhere in the car, likey places are under the rear seat inside the drivers door panel or under the headliner board, you will have to crawl under the car and on the passenger side axle tube facing twoards the front of the car there should be a code stamped such as AJ or 2BK for example. it may take some wire brushing or sanding to find it but when you do post what you find and me or someone else will be able to tell you what you have.

 

[Bar50]

You will be AMAZED at what adding 3.23 or 3.42 gears to your car will do!

If your 307 has a Q-jet/ 4 barrel carb, just get some gears and a posi unit...it will really WAKE UP your car!

S-10 gears will fit, there are 26 and 28 splines out there, so, if you pull a set from the salvage, take carrier, bearings, races, side spacers, and all...you may have to RE-use your (axle) spiders gears if it is just an open diff....some guys will tell you "no they are 7-1/2" and 7-5/8" they will work, been there, done that, does require pulling the bearing races out of the housing...

It will make way more of a difference than exhaust.

 

[shanghaismith]

You will be AMAZED at what adding 3.23 or 3.42 gears to your car will do!
It will make way more of a difference than exhaust.

X2 on the 3.42 gears. I used to have a 307 and 2.xx gears, what a dog! The 3.42's made a huge difference. If you buy the gears and pay a shop to install them I think you will have less money into it than headers and dual exhaust. Any mods to the 307 will not increase power very much, unless you spend 2 or 3k.

 

[Bladecatcher82]

Thanks for all the replys, definitely a huge help! I have been busy with work and school and havent gotten underneath to check my axle for any codes, but i plan on doing some work on it monday, and I'll keep you all posted! thanks again guys.

 

[jetsetw31]

If the car was originally a diesel, then your transmission is a TH350. Look at the tail housing, if it has four removable bolts it's a TH350 trans. I know GM did some stupid things, but i don't think putting a TH200 behind a diesel was one of them. Lol
T

 

[Bladecatcher82]

jetsetw31, I think I see the 4 bolts on my tail housing, but would a thm200 not have a removable tail housing like the 350? because all the pics on google (i.e. http://images.oreillyauto.com/parts/img ... driver.jpg ) don't show anything similar to the 350. I just dont know jack sh*t about transmissions haha, but I definitely have 4 bolts on my tail housing, just like this:http://paceperformance.com/images/F15185988.jpg. There are four bolts connecting the tail housing to the transmission in the bar right of the pic. I have that. lol, sorry for my stupidity. but as of now I'm assuming I have a 350. Thanks for all the help!

 

[Bladecatcher82]

And the code is 2BJ0 011

 

[spidereyes455]

2BJ comes up as a 2.41 posi. You could ditch the 2.41 gears and put in 3.08's and still keep your posi carrier, it wont turn it into a fire breathing monster but it will wake it up and with 3.08's youll still be able to cruise the highway even with your TH350 trans.

 

[Bladecatcher82]

If I wanted something more like 3.23, I wouldn't be able to keep my carrier? Could anyone possibly be able to tell me what carrier would fit? I hear a lot about s10's gears fitting. Thank you

 

[spidereyes455]

2.14 to 3.08 uses a 2 series carrier. 3.23 ,3.42, 3.73 , 4.11 ect use a 3 series carrier.