My 84 has a TH350 trans in it, I think the tail housing is off a 700R4 but I cant get any answers from anyone if they swap, some say yes some say no. The pics are not great but any help I thank you for in advance, I just want to know what I have. I want to put real gauges in and I see it has a plug for electric but I dont know if the two trannys "mesh".
http://www.smokinvette.com/corvettephotos/data/750/medium/041.JPG
http://www.smokinvette.com/corvettephotos/data/750/medium/042.JPG
http://www.smokinvette.com/corvettephotos/data/750/044.JPG
http://www.smokinvette.com/corvettephotos/data/750/043.JPG

The 700r4 housing will bolt to a th350. With a proper length spacer to locate it correctly it will bolt up to the c beam. Electric? What gauges?

Race on!!!

Are you sure you have a TH350 in your '84? That doesn't make any sense to me. How did you determine it's a TH350 and not a 700R4? It came with a 700R4 from the factory.

Electric? What gauges?

Race on!!!
sorry...speedometer, do the 700/350 gears mesh, my car has no speedometer now & Im going to put analogs in & need to find out what will work
Are you sure you have a TH350 in your '84? That doesn't make any sense to me. How did you determine it's a TH350 and not a 700R4? It came with a 700R4 from the factory.

yes its a 350, 3gears & the pan is how I know, but I know the shaft is not orig. the C-beam has been modded.

sorry...speedometer, do the 700/350 gears mesh, my car has no speedometer now & im going to put analogs in & need to find out what will work. just use the th350 speedo gears and a speedo cable. I don't know if the 350 and 700 gears are the same or not, maybe, the 700r4 gears are the same as some 4x4 transfer case gears.


yes its a 350, 3gears & the pan is how i know, but i know the shaft is not orig. The c-beam has been modded.the spacer for the tail shaft housing doesn't require any c beam mods. It just bolts up.

race on!!!

[QUOTE=LT1-84;478189

yes its a 350, 3gears & the pan is how I know.

[/QUOTE]


The guy who swapped it must have been on drugs or he was crazy. Nobody in their right mind would do such a ridiculous swap.

I have to agree, why would anyone take out the 700r4 and replace with a th350?

I have to agree, why would anyone take out the 700r4 and replace with a th350?

Some do it because the turbo 350 has gear ratios more suited to a drag car.
To answer the op's question, that is a c4 vette tailhousing. The same part was used on all c4 corvettes from 84-96. With the speedo drive gear located in the correct spot, any cable or electronic speed sensor for a 700 or 350 can be made to work easily. This assumes the correct width spacer is used between the tailhousing, and the case to properly position the speedo driven gear.

Currently the speedo sensor is only acting as a plug to keep the fluid in. Without the correct tailshaft and spacer, you will not make it work.

Ok , let me rephrase the question..Why would anybody swap a 700r4 to a th350 in an otherwise stock car like the op has? When a properly built 700r4 with the lower 1st gear ratio and the option of overdrive, allowing for use of much larger rear axle ratios, makes for a much better street/strip combination.and is better on fuel for hiway driving.Maybe I m missing something ,but I just see no advantage to a th350 on a street driven car...and If it was for drag racing only, th350 is certainly not my first choice.

Ok , let me rephrase the question..Why would anybody swap a 700r4 to a th350 in an otherwise stock car like the op has? When a properly built 700r4 with the lower 1st gear ratio and the option of overdrive, allowing for use of much larger rear axle ratios, makes for a much better street/strip combination.and is better on fuel for hiway driving.Maybe I m missing something ,but I just see no advantage to a th350 on a street driven car...and If it was for drag racing only, th350 is certainly not my first choice.

Who are you asking?
If it's me, all I could assume is that they disagree with you. I built 3 or 4 a year for different c4 guys that did prefer it, for their reasons (whatever they were).
As I mentioned earlier, some prefer the gear ratio's of a 350 for their specific combination. In some cases, the steep first gear of a 700 combined with the huge rpm drop into second gear is counterproductive to a specific combination.
I have also seen guys use powerglides, turbo 400's, 4l80e's and 2004r's in c4 vettes. Some guys like myself have opted for different planetaries in the 700 to tighten up the gear spread.
Maybe the guys that have strayed from the flock will chime in and offer input.

Who are you asking?
If it's me, all I could assume is that they disagree with you. I built 3 or 4 a year for different c4 guys that did prefer it, for their reasons (whatever they were).
As I mentioned earlier, some prefer the gear ratio's of a 350 for their specific combination. In some cases, the steep first gear of a 700 combined with the huge rpm drop into second gear is counterproductive to a specific combination.
I have also seen guys use powerglides, turbo 400's, 4l80e's and 2004r's in c4 vettes. Some guys like myself have opted for different planetaries in the 700 to tighten up the gear spread.
Maybe the guys that have strayed from the flock will chime in and offer input.
I m just curious, you said th350 was better suited for drag racing..I know I went from th 350 to 700r4 in my 81 and I have to tell you , I would never swap back..The 700r4 makes my car so much faster,and yet more driveable, with 3.73 gears , in overdrive, I m only turning 2500rpm at 80mph..and the lower 1st gear lets my .568/.572lift cam come alive. So Im asking why th350 is better for street application, or was it just a cost consideration?

Ok , let me rephrase the question..Why would anybody swap a 700r4 to a th350 in an otherwise stock car like the op has? When a properly built 700r4 with the lower 1st gear ratio and the option of overdrive, allowing for use of much larger rear axle ratios, makes for a much better street/strip combination.and is better on fuel for hiway driving.Maybe I m missing something ,but I just see no advantage to a th350 on a street driven car...and If it was for drag racing only, th350 is certainly not my first choice.

the guy before me got the car without a drivetrain, I think he used it because it was cheaper, the car was a 4+3 car & still uses the 4 speed shifter. Im reworking some of this as I can, some things that were done are good & some look like a kid did them. I dont think there is a spacer between the case & tail but Ill check and see. the C beam was lengthed I think, so no spacer. Thanks for the help, I wasnt getting good answers from anyone.

Some do it because the turbo 350 has gear ratios more suited to a drag car.
To answer the op's question, that is a c4 vette tailhousing. The same part was used on all c4 corvettes from 84-96. With the speedo drive gear located in the correct spot, any cable or electronic speed sensor for a 700 or 350 can be made to work easily. This assumes the correct width spacer is used between the tailhousing, and the case to properly position the speedo driven gear.
Thank you, this is the info I needed

Currently the speedo sensor is only acting as a plug to keep the fluid in. Without the correct tailshaft and spacer, you will not make it work.

the guy before me got the car without a drivetrain, I think he used it because it was cheaper, the car was a 4+3 car & still uses the 4 speed shifter. Im reworking some of this as I can, some things that were done are good & some look like a kid did them. I dont think there is a spacer between the case & tail but Ill check and see. the C beam was lengthed I think, so no spacer. Thanks for the help, I wasnt getting good answers from anyone.
So it was just a cost thing by previous owner..Now I see.. I know you probably don t want to put out the cash to switch now, but if you do at some later date,the 700r4 is a much better option in my opinion.. Is the engine still basic stock or has it been modified too? Well good luck on you project.

with 3.73 gears ,and the lower 1st gear lets my .568/.572lift cam come alive.
I disagree ;
have same combo with my 383 (234/242 ) and 1st gear is wasted .
I have to start with shifter in 2nd at the strip because I can't shift out of 1st fast enough before engine redlines (6500 ) and then there is the big rev drop off into 2nd
The 2.XX 1st gear of a TH350 or TH400 would be of more benefit to me giving a longer run out in 1st gear ,closer split into 2nd gear as well as dialing out some of the off the line torque
The 3.07 1st gear of a T700 is great for under powered cars to give the torque multiplication needed for punch off the line; if you have decent power you don't need it and the ratio spread can work against you

So it was just a cost thing by previous owner..Now I see.. I know you probably don t want to put out the cash to switch now, but if you do at some later date,the 700r4 is a much better option in my opinion.. Is the engine still basic stock or has it been modified too? Well good luck on you project.

If I do a swap I have a friend of mine the has a ZF he'll sell me cheap, so thats the way I'll go. As far as the 350 goes I love it & Im glad its in there. The engine is a stock 93 F body LT1 with a carb, nobody likes that either but Im not one for injection, I can work on it & thats what I like. I hope to have this thing back on the road before the snow comes but I super swamped at work so we'll see. Thanks again.

I disagree ;
have same combo with my 383 (234/242 ) and 1st gear is wasted .
I have to start with shifter in 2nd at the strip because I can't shift out of 1st fast enough before engine redlines (6500 ) and then there is the big rev drop off into 2nd
The 2.XX 1st gear of a TH350 or TH400 would be of more benefit to me giving a longer run out in 1st gear ,closer split into 2nd gear as well as dialing out some of the off the line torque
The 3.07 1st gear of a T700 is great for under powered cars to give the torque multiplication needed for punch off the line; if you have decent power you don't need it and the ratio spread can work against you
You may be correct for track application only, but for everyday street driving and hiway cruising and the occassional street challenge, the 700r4 is superior..Which was my point, it makes it much more driveable..my cam is 258/262 duration full roller with redline at 6800rpm, 27in tall tires also give me a bit more speed at same rpm..I have no problem with 1-2 shift, except that it spins tires for about 20-30 feet.there is no lag in my motor

If I do a swap I have a friend of mine the has a ZF he'll sell me cheap, so thats the way I'll go. As far as the 350 goes I love it & Im glad its in there. The engine is a stock 93 F body LT1 with a carb, nobody likes that either but Im not one for injection, I can work on it & thats what I like. I hope to have this thing back on the road before the snow comes but I super swamped at work so we'll see. Thanks again.
I personally prefer a carb as well..I run Quickfuel on my stroker..performs beautifully.. keep us informed on progress

except that it spins tires for about 20-30 feet.there is no lag in my motor
Same here , controllable on street with throttle but pointless at the track if you have to back off to get traction

Same here , controllable on street with throttle but pointless at the track if you have to back off to get traction
that was my point all along..the op doesn t race, has stock motor,..the best choice is the 700r4..for strickly drags, maybe not...I personally love the damn thing..Its lightning quick with my set-up and hi-way friendly too, and still 20-21mpg in overdrive..how can you beat it? and as for durability, my motor is over 500hp and it can t break it.