[chevyracer5613]

69 firebird , currently , th350 w/ hydraulic shift kit , 3.23 rear gear

i have the engine out of my car since im doing a rebuild and was thinking about ditching the 3 speed , its strong but i need something that will do better on the highway and still hold a good bit of power

id like to convert to a manual but im not set on it by any means , i was thinking about a t56 but the cost of that is pulling me away , so i was just curious on some opinions

goals with my car is, enough power to run mid to low 12's (Eventually) and still cruise 80 on the highway without having my RPM'S real high lol

ideas , opinions , cost assumptions????

[TTS]

A 700R4 would work well with the 3.23's, you would net a 2.26 final drive plus LU. In low it would be similar to a 3.90 so it's win win IMO. Cost may be a factor, 2K ish for a x member, driveshaft, cable & bracket, transmission and converter. Pontiac power? You need the adapter too.

[chevyracer5613]

thats actually one that i am considering , i heard they are costly to build up so they can hold the power , is this true?

[TTS]

What kind of power? It doesn't sound like you're looking for more than 400-450 HP or so. They're as strong as 350's so that kind of power isn't a problem, attention to detail in assembly is more important than most of the parts. That said, there are a LOT of wearable parts in a 700 compared to most RWD's so yes it will be a little more expensive- plus a core and retrofit. I've got 2 700's later this week, I'll PM you for a better idea of prices to expect so you can shop- if I forget, just remind me.

What engine????

[chevyracer5613]

yes 450 is about where i want to be with power , i figure that should be good for a nice street/strip combo

400 engine

sounds good , thanks for the info!

[Brad B. Hillebrand]

I run a 700R4 with 520HP and 580TQ. I had to get the BOP adapter and for my GTO a shifter conversion from ShiftWorks. Car goes like mad.....first is awsome with a 3:55 acting like a 4:10. Cost was about $4,600. Adjusted right the first time as well. This guy builds the trans for many of the top NMCA guys like Tony Nesbitt, Ort's and Curran etc...

Honest and straight forward. Good to deal with.


http://www.tsiracing.com/

[brianberes]

I want one of those 700R's, but that's mucho money for a tranny. I just bought my engine from boardmember Ponchospidel. It was his strip engine in his ventura and it is putting out around 550 hp, so I need a tranny that is stout. Do you have any video of your car going down the track with the 700r tranny? I looked on the website and they don't advertise the 700r???
Brian

[Brad B. Hillebrand]

If you are asking me, no videos sorry to say. I've had the tranny for about a year and I do drive the car often and run it hard.

Here is another place that just poped up. I read about them in Hemings and now they are adversiting in Hot Rod mag etc...

http://www.gearstartransmission.com/

Prices start at $4K and go to $6K for electronic versions....

[Formulabruce]

Around 1900 will get you a stage 3 ( 500 hp) th2004R with a .67:1 final drive ( highest rwd ever made I think)( the 700 is .70) NO special plate needed ( was used in the 89TTA pace car and the buick GN., GNX. get a later model case and get it built by someone who knows them. Shiftworks has some stuff as has been stated.

[chevyracer5613]

hmmm th2004r sounds intruging , wonder if i could find a built one used for cheap haha

[gman26]

Would it be easier (and cheaper) to just change the rear gear from 3:23 to maybe 2:56, instead of swapping my TH400 for a 700R. I'm looking for lower RPM at cruise, hence, better mileage on the highway.

[Overkillphil]

2.56 and a 3 speed auto is a terrible combination, unless you are driving the autobahn or Bonneville salt flats.

First gear takes forever and upshifts over 50 mph! Like trying to peddle a 10 speed bike up a steep hill from a standstill in 10th gear!

Besides, you would also have to change your carrier in the rear. Now it's getting expensive...

[b-man]

Originally Posted by Overkillphil

2.56 and a 3 speed auto is a terrible combination, unless you are driving the autobahn or Bonneville salt flats.

First gear takes forever and upshifts over 50 mph! Like trying to peddle a 10 speed bike up a steep hill from a standstill in 10th gear!

Besides, you would also have to change your carrier in the rear. Now it's getting expensive...

I had the TH400/2.56 combo behind a mild 8.2:1 compression 068-cammed 455, it was nice out on the highway and still pulled off high-13s in the 1/4 mile without much effort.



However around town the 2.56 gear requires more throttle opening to get the car moving, translating to poorer city fuel mileage (9 city/13 hwy).

At the track I shifted out of first at 55 MPH and went across the finish line at the top of second gear at 102 MPH. Out on the highway it was fun to downshift into 2nd at 80 MPH and take it up to 100, then shift to 3rd and have it still pull pretty hard up to a 140 MPH top end.

Here's one of the tail lights seen by more than one 5.0 Mustang that tried to chase it down.



Unless you're on the highway all the time, the 2.56 gear/3-speed auto isn't the way to go. Now that I don't drive the Tempest on the highway much anymore a 3.36 gear is replacing the 2.56 gear. City mileage should improve, and acceleration too.

You can get a 700R4 trans and converter here for about $1500, Hubbe runs a good honest business and builds a very nice 700R4 (his specialty):http://www.hubbes.com/

[SGTGTO]

TKO 600

[gtome]

I would have to agree with b-man. I have a 65 Tempest with a built 455 (450hp?) and it had a 2:56 one legger in it and I thought it was great. Not good on gas, but had plenty of grunt to get around town and still pulled high 13's after sping 600ft. Speaking of spinning, how much fun is it to light the (tire!) up driving past ricers at 55 mph! No problem with that tall single legger! I swapped that rear out for a 12 bolt and put an Eaton posi with 3:42 gears in it and blew the engine half way to the track. Sure didnt like the extra revs on the highway, but I wanted more at the track so... Looks like I may end up going overdrive too. Maybe I should have left that one legger in it and been happy, sure was a good cruiser...and no slouch either.

[68birdfreak]

TKO600rr
I love the way my 5spd launches and at any time in three gears you can light er up with 355's. Few things are as cool as shifting when it comes to Old School muscle...
JMO

[GT182]

Try Keisler if you want to switch to a manual tranny. Prices aren't bad for the fulll conversion from auto to manual. It's a custom swap with everything included. They even do a repro of the Hurst shifter too.
http://www.keislerauto.com/gm/index.html and http://www.keislerauto.com/gm/transm...64-67_auto.asp

I'm thinking of doing the 4 to 5-speed route for better driveability and gas mileage on my 66 Goat.

[chevyracer5613]

hmm tons of good options , wish i had 4 grand to spend haha

ill most likely end up getting a 700r4 , mainly due to the fact the i have a freind that rebuilds them all the time

it'd be nice to have a 6 speed tho , my buddy corvette gets about 23 mpg on the hwy (75 mph = like....1500 rpms) , wouldnt that be nice in a firebird haha

[b-man]

Originally Posted by chevyracer5613

hmm tons of good options , wish i had 4 grand to spend haha

ill most likely end up getting a 700r4 , mainly due to the fact the i have a freind that rebuilds them all the time

it'd be nice to have a 6 speed tho , my buddy corvette gets about 23 mpg on the hwy (75 mph = like....1500 rpms) , wouldnt that be nice in a firebird haha

You won't be hurting too bad with the 700R4, my '02 WS6 has the electronic version of that trans (4L60E w/3.23 rear) and it recently pulled off 26 MPG on a highway trip with the top down!

[Colin Frolick]

i love all the pictures of Tempests on this thread

(mine has a 6 speed stick!)