After running the vette for a few days now, it is clear that I need more than the 3 gears I have. High speed motorways and its as though the engine is screaming for another gear.

What do you guys recommend I do to get at least another gear. Is there a 4sp auto box I can just swap out and what are the costs involved? Are there any major modifications required?

If I looked at manual boxes I assume they would be alot more work and $$$$?

Thankyou.

 

Both the 700R4 and the 200-4R can be made to work in a C3. 200-4R install
I bought mine from Bowtie Overdrives for about $1700 complete. The 700R4 takes a little more work because th driveshaft has to be shortened and the crossmember needs to be replaced.

 

I had the same issue after putting the new stroker in last year. Everyone recommended the 700R4 or TKO500/600's. It seemed to me that more people had issues with the TKO installs. Keisler reps are crawling around the forum frequently doing damage control. They seemed helpful to me though. Keep in mind what you want to do with the car later. Most of these have HP limitations.

Mine is in the shop getting the Viper t-56 as we speak. I think they need a really big shoe horn to get it in and it is not a job for a budget.

There are alot of old threads on the TKO's, T-5, T56, and 700r4s. Run a search.......

Good luck

 

Had the same "problem" with mine shortly after I got it. When cruising on our motorways at the normal traffic speed with the engine revving away, while the exhausts were bellowing & the fuel gauge sinking, got me thinking the same thing. After lots of research I went for a BTO Level 2 200-4r. Fitting it was easy (much easier than I thought it would be) & the results are awesome. With the stock rear ratio of 2.87:1 I'm now running 75mph @ 2000rpm (was 70mph @ 3000rpm). Fuel economy has dramatically improved when cruising & the slightly lower ratio low gears make for better acceleration from standstill (which an L81 needs ). It's really nice being able to cruise at high(ish) speeds with the engine just burbling away. It's THE best thing I ever did to mine & has dragged it into the modern world.
Costs weren't too bad, considering what you get, but it cost me more than most people due to shipping across the Atlantic, having to pay a mate to sleep outside customs for a night (whoops!) & the poor exchange rate at the time. I estimate that it's probably saved about 1/3 of it's cost in fuel over the last 4 summers.

edit:
That's not American! Are you in the UK??????

 

Yes UKPaul. Just waiting for the british weather to improve. If you dont mind me asking, How much was your box and where did you buy from. Also you say it was easier than you thought it to be. How long did it take, did you need any special tools and was it instantly driveable or did you need to tinker?

thanks

 

Hi,
I got it from Bowtie Overdrives http://700r4.com/sitemap.shtml
I'll can get back to you with the total cost (need to find the reciepts) but I'm guessing at about £1400. This included me messing up & not ordering a custom x-member with the rest of it (the stock '81 x-member won't work) so I got hit hard with postage on the x-member (shipping cost more than the x-member itself & then I got hammered for tax & duty on both the x-member & the shipping). Shipping of the trans was from their shop to Ipswich docks & I got a mate who runs a Despatch company to pick it up from there. When he delivered it I realised that it was easy enough to lift the box on my own & that it would have fitted on the back seat of my car! At the time the exchange rate wasn't in our favour, so it may work out cheaper now? I'm supposed to be putting together an article for the CCCUK mag on the installation, so I could email you it if you want (any good at proof reading? It's only taken me 2 years to get this far with it ).

Fitting was really simple. The most difficult things were getting the car up in the air enough to slide the trans in/out from underneath (I made up some interlocking spacers from lengths of 4x4 & fitted a couple under each wheel) & not letting it snowball into various other jobs! Getting the trans out was easy once you work out how to remove the 2 top bolts. You need to remove the driveshaft (I needed to buy a 12 point 1/4" socket for the UJ straps & highly recommend getting a pair of new UJs before you start), speedo cable, shifter cable, drain the fluid, there's not a lot to it really. The instructions that come with it are very comprehensive, apart from one glaring ommission regarding the dipstick/filler tube. You can fit the trans with the tube in place, but it makes it more awkward as you need somebody to guide it through all the wires & vacuum pipes in front of the firewall. It's far easier to fit the trans & then fit the tube afterwards. However you do it, test fit the tube to the trans before fitting it in the car & bend the mounting tab on the tube so that it lines up with the bolt hole. Trying to do this with it all bolted into the car is almost impossible. I think the hardest thing about the whole installation was fitting the kit to the carb (a new cable, the TV cable, has to be mounted to the carb with a kit they supply) & modifying the shifter itself (which means taking the console cover off). Neither of these 2 jobs are difficult & I reckon that I could do the entire swap again in a leisurely weekend (or a day if I was in a hurry). I honestly think that changing the intake manifold is more tricky (but not as heavy!). "Gotchas" include things like cleaning up the underside & painting it, fixing lots of Bubba wiring "mods" under the centre console, building an exhaust system from scratch, replacing driveshaft & halfshaft UJs, painting the shafts, etc, etc, etc! What I would suggest is to replace the UJs as you'll have them apart anyway (& finding that they need changing & having to wait for some to arrive can be frustrating) & also, if you're running a Q-jet, get the throttle shaft repair kit (it's just a couple of brass bushes you fit after reaming out the shaft "bearing" holes in the body. Somebody on this forum will know where to get the kits.
Once it's all fitted you need to adjust the TV cable (buying their pressure gauge makes things so much easier from this point onwards) & phone them with the pressure readings. If they're OK (ie you've not messed it up somehow) then you need to go for a test drive with a passenger who will note the pressure readings & shift points. You then phone them with this info &, if it's what they expect, then you're free to enjoy it.
My experience was that their pressure gauge is a must as it makes setup & testing a piece of cake. Also highly recommend the fluid temp sensor & gauge. Then, with the temp gauge, you'll see that in low gears the fluid temp climbs well above what the ideal is, so a trans cooler is a very good idea. I got mine from Real Steel in Uxbridge &, not only has it dropped the fluid temp, it's also dropped the coolant temp as well. Don't bother ordering a converter cover as they are for 153 tooth flexplates (ours are 168 so it won't fit). I carefully made up spacers for my old Th350 cover so that it'd fit OK, but I have it on good authority that some careful work will modify it so that spacers aren't needed (it seems that just laying into it with a large hammer does the job).
If you do decide to go this route & need any advice, just ask. One thing's for sure...... 4 years later I'm still driving down the motorway at, er, speed, in "3" & then shifting into OD & loving the drop in rpms The only ****le I have with it is that it stays in OD at very low revs (1000rpm = 40mph) & you need to manually shift it out of OD at speeds below anything below 50-60mph (or whatever point the engine feels like it's starting to lug). It's no big deal, but worth being aware of before you consider buying.

 

i have the 700r4 and i like it

 

well said Paul, paul da man, he helped guide me thru my 200r4 swap

 

The easy choices are 2004R, 700R4, and Keisler. They fit easiest and work great with less headaches.

The more difficult ones would be retrofitted T-5s and t-56s from F-bodies, Vettes, and Vipers.

 

The crossmember doesn't need to be replaced using a 700, I used my original one.

 

Tell me more shafrs3. What exactly did you have to do to it?

 

it has a angle bracket that hooks up to the origional crossmember no need to modify crossmember bolt the angle to it

 

why would any one want to keep the original crossmember???? the BTO one is significantly lighter and it is high so you have no exhaust issues.....other then trying to figurer where to put the exhaust hangers

 

$200 Bob.
Plus I don't have any exhaust issues (side pipes).

 

I fabricated a simple L shaped bracket that bolted to the front of the X-member for the trans mount to rest on that's it.

 

I'm not convinced it's as stiff as the original.