I have an 88 Firebird with Axle Code 6HP, Over the summer i replaced my 305 and Manual trans With a Syclone 4.3 Turbo and
700r4 Trans. I have't had any problems with the swap but it feels like theirs alot more to be released, So my question is what would be the best for my swap to finish it out.

 

if built right the 700r4 will handle what you have but another option is the bullet-proof th400 if you want to stay automatic

 

sweet engine choice. pics or ban!!

 

The cyclone drivetrain would be cool. Hmm awd camaro. Anybody got a truckload of money i can borrow.

 

ya it did brake me but it was worth it , Anyway what i ment is what gear ratio should i get. When i try to launch i can only get to
3 lbs of boost then it starts spining the rear i have 273 std.
I'm looking for 345 posi and i don't know if this will work or not,
are the carriers the same or do have to get the whole rear axles
and all. or would 373s be better i don't have any idea yet.
I know i could figure it but i can't afford my car to be down anymore than it has too. I'll take some pics this weekend and post.

 

You have a 2 series carrier and the 3.42 ratio is a 3 series. You can either get a 3 series differential and and use a 3 series gearset. Or you can stay 2 series and get a gearset in the ratio you want in 2 series. They do actually make 3 series gearsets to fit the 2 series carrier.

 

is there an easy way to tell the difference between 2 and 3 series carriers? i have an auburn posi carrier, but i couldnt find which one it was online.

 

or how about a ford 9" rearend and if so what car can i get it from
and is there much mods or should just get a 345 rear out of a junk yard

 

If you could find a posi in the junkyard i would definately give it a try, hell its only a few buck so who cares if it only lasts for a summer.

 

Generally speaking any gearset 3.08 and numberically higher is going to be a 3 series. However its possible that a gearset using a 3 series number was used in a 2 series carrier.