390racer

Hi
can anyone help with info on converting a 427 tri power to auto not sure of which trans would fit best without major mods prefer bolt up deal so if need be can convert back to manual.
Also good source to locate everything.
Thanks

GearheadJoe

A good starting point for consideration is the 700R4 4-speed automatic. This transmission has a 4th gear that is an overdrive, which is an improvement over the venerable turbo 400 3-speed automatic. The 700R4 uses a mechanical throttle position sensor (TPS), so there are no electronics or computers involved. One company that sells conversion kits is Bowtie Overdrives.

The 700R4 will fit fine in a 67 Corvette, but the drive shaft will have to be shortened. I think that a 2004R 4-speed automatic will bolt in with no changes, but these are not as strong as a 700R4.

If you don't mind adding an electronic shift control module, there are electronoc versions of the 700R4 such as the 4L60E. However, for a 67 Corvette, I think the 700R4 with a mechanical TPS is a good match. Original 67 Corvettes with a Powerglide used a mechanical TPS.

BTW, this is an easy swap using reproduction factory parts. I have performed the reverse operation (Powerglide to Tremec 5-speed), and it was easy. The pedal assembly was designed by GM to easily convert between manual and automatic by simply changing the pedals. You will need to add a transmission fluid cooler, but reproduction parts for a Powerglide application can be used.

For the shifter, it should be possible to use an original or reproduction Powerglide shifter. The aftermarket even makes original-style shifter plates for the 700R4 that show the additional gear positions.

Original shifter consoles for automatic Corvettes are widely available, since the 4-speed consoles are in greater demand. Even NOS automatic consoles are availabe at reasonable prices (compared to NOS manual consoles).

plaidside

A friend of mine has a P/G that came out of his 65 Coupe when he switched to a 4 speed. He might have some other parts; if you have interest I will ask him.
Joe

Nowhere Man

To add what Joe said BB autos did not have a separate cooler. The end tanks on the rad had the cooling line fittings. And I'm 99% sure your not getting a auto in without pulling the engine first.

390racer

Thanks for the replies, I am tossing up between the Turbo 700 and a 400, problem with the 700 is the throttle position cable is super critical and if not correct trans burns out quickly.
My biggest hurdle so far has been locating a brake pedal everyone seems to advertise a 63-66 or 68 on.

Nowhere Man

I could have one for sale

Frankie the Fink

IIRC '67 brake pedal ***'y is one year only. If Nowhere Man has one I'd jump on it.

Converting a 427 tri-power to automatic ? Isn't that a felony ?

390racer

If you do let me know.
Thanks

Nowhere Man

I would not call it that Frank. Not if he has a medical condition that does not allow him to enjoy his car. I only have the pedal arm it self with out the pedal box. I also have some other big block auto parts. I am not home to get pictures

Nowhere Man

What all parts do you need. I am not home for the weekend so I can't get you pictures of what I do have left over from my last build of a BB auto.

390racer

Frank
the owner has become incapacitated but still loves his vette he had 2 choices sell or convert so convert it is

V8Heart

I recently purchased a manual 67 but due to health problems can't use the clutch pedal. My 68 is auto so no issues, but I also have a manual miata that had installed a system that allows the driver to push the clutch by pressing a button thru a mechanical/electrical device.
The systems here in Europe is distributed by Guidosimplex.
I thought about converting to car to automatic but didn't like to change the original features also because this device needs no more than drilling a couple small holes in the firewall.

Here is a link to the product
http://www.guidosimplex.it/english/p...lutch%20series

Btw, used to track the miata, so no worries for the correct setup of the system

Frankie the Fink

I was kidding of course and have no problem with anybody changing a car around to handle a health situation. I believe one member here has hand controls in his split window coupe. Drive 'em, I say

BADBIRDCAGE

Once the clutch pedal linkage is removed you can leave the pedal in the car and secure it in a fully depressed condition. You do not HAVE to install an auto style brake pedal.

GRG

My research reveals you should sell your car and buy one with an automatic. A lot less trauma to your sanity I promise.

colo63sw

I am getting on in age a LITTLE and live in an area with a lot of stoplights. And I actually drive my 63 to go places (as opposed to countryside jaunts). Going through gears every couple blocks due to stoplights is repetitive and boring, I have been doing it for over 40 years.
I have 0 problem with people converting to an automatic so they can drive their stylish car with comfort and convenience.
Not everyone maintains their car so that they can thrash an aurocross course.

GearheadJoe

The throttle position sensor (TPS) on a 700R4 is mechanical and is operated by a cable. The transmission uses the TPS as an input to decide when to up-shift (say, 2000 RPM under light throttle and 5000 RPM under full throttle). Downshift timing is also affected by the TPS.

I have not heard of a mis-aligned TPS causing transmission burn out, but I have heard that if the TPS is not properly adjusted, the up-shifts and down-shifts will not occur when you might like.

I believe that Bow Tie Overdrives (www.bowtieoverdrives.com) claims to have a superior solution for getting the TPS to work well. Keep in mind that the 700R4 was used for many years in GM cars and the TPS worked fine for them. So, it's just a matter of getting the retrofit TPS set up correctly.

The turbo 400 also uses a mechanical TPS, but it uses a rod-type linkage similar to what the stock Powerglide used. That might be slightly easier to adapt.

However, if you plan to do any amount of highway cruising, I would recommend the 700R4. The 4th gear overdrive is a really nice feature that the Turbo 400 lacks.

Also, if you want to avoid fooling with a mechanical TPS, you can get a 4L60E, which is pretty much a 700R4 with electronic control. The TPS becomes a simple electronic sensor on the carb. I believe a few companies offer a little "box" that will manage just the transmission based on an electronic TPS. These boxes usually have a couple adjustments for setting the shift points.