4 speed versus 5 speed trans

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Cool I can splice wires

This conversion dont really sound that complicated, I may try and start aquiring parts soon, I`m thinking the 5 speed would be better for me for obvious reasons.

$10.50 for the tranny, wow......

Ok, it sounds like if I go the 4 speed, I wont have to alter the tranny tunnel, but if I go the 5 speed, it sounds pretty positive I`ll have to do some fab work right?
 
to the tranny neutral safety switch, that the car wouldn`t start at all, that the circuit wasnt complete or something, I may very well have misunderstood this though.

Sounds like if I went the 4 speed, the close ratio would be more fun....

Ahh yeah, I forgot about the connector on the firewall. It'll have (4) holes for two circuits: one going to the backup lights, and the other circuit that goes to the neutral saftey switch on the C-4.

Off hand, without looking at the wires, or looking in the shop manual I don't remember which wires are what, but it would be simple to readout with an ohm meter to determine what goes where.

To bypass the neutral saftey switch for the manual transmission, all you would need are two .157" male bullet terminals and a very short piece of wire. Crimp the terminals onto each end of the short wire, and then plug the terminals into the firewall connector to complete the circuit. This will bypass the saftey switch that was on the C-4 --just be careful, 'cause now the car will start whether the transmission is in gear or not.

If you wanted to hook up the neutral saftey switch on the T-5, Run a wire from the firewall connector down to the switch on the T-5, then run a return wire from the other side of the tranny switch back to a switch mounted on the clutch pedal support. From the other side of the clutch switch contact, run a wire back to the firewall connector. This will complete the circuit, and the engine would only start then if the clutch pedal is pushed in.
 
IMHO the best upgrade one can make to these cars is a manual trans with overdrive. I had a Gforce T5 (beefed up T5) installed in my car it has a .59 O.D. 5th gear.
With my 3.89 rear end I can cruise at 75mph @ 2100rpm's:D
Scott
 
I`m trying to think of possible issues with this

I want to know for sure if the T-5 is gonna require transmision tunnel fab work.

I have a factory air car, and if I alter the tunnel, is it gonna affect the way my air conditioner unit sits under the dash in any way.

Surely some of yall have crossed this bridge.
 
I want to know for sure if the T-5 is gonna require transmision tunnel fab work.

I have a factory air car, and if I alter the tunnel, is it gonna affect the way my air conditioner unit sits under the dash in any way.

Surely some of yall have crossed this bridge.

In my case ('68 coupe), I didn't have to modify the floor. The shifter is located slightly more forward in the hole than my top-Loader's shifter was, but in my case, the T-5 shifter came right up through the hole with no cutting.

http://img68.imageshack.us/img68/9268/68gaugesnf6.jpg
 
Sweet gauges man.

One of you guys indicated I might have to cut into the trans tunnel because the bellhousing on the T-5 is taller. I`m curious if I do cut into it, making the tunnel bigger, will I also be cutting into how much room I have under the dash for my air conditioner unit? I will be raising the floor under the ac unit, but will it be enough to interfer with my instalation of the ac (its the under dash mounted external unit).

I`m trying to keep from getting into a situation I cant get myself out of.....
 
One of you guys indicated I might have to cut into the trans tunnel because the bellhousing on the T-5 is taller. I`m curious if I do cut into it, making the tunnel bigger, will I also be cutting into how much room I have under the dash for my air conditioner unit? I will be raising the floor under the ac unit, but will it be enough to interfer with my instalation of the ac (its the under dash mounted external unit).

I`m trying to keep from getting into a situation I cant get myself out of.....

My good friend and business partner, Glen Buzek ( www.rosehillperformanceparts.com ), rebuilds T-5s. He has a Z-spec in his '65 coupe. I'm unaware of any modifications, like you describe, being done to his '65 in order to install his T-5 in that body(??).

You could go to Glen's link above and email him about what he did to install his T-5. If you want to inquire if he has any T-5s ready to install, you could also ask then --tell Glen 'Ultrastang' sent you.:nice:
 
My '67 coupe required elongating the C4's crossmember holes that mount to the body. I needed to drop the tranny about 1/8" to 1/4". It just barely touched the tranny tunnel otherwise.
 
There is some good stuff on there

I already found some great info, and jsut started browsing the site.

I may call this guy in January, I got a big project keeping me tied down till then.
 
One of you guys indicated I might have to cut into the trans tunnel because the bellhousing on the T-5 is taller. I`m curious if I do cut into it, making the tunnel bigger, will I also be cutting into how much room I have under the dash for my air conditioner unit? I will be raising the floor under the ac unit, but will it be enough to interfer with my instalation of the ac (its the under dash mounted external unit).

I`m trying to keep from getting into a situation I cant get myself out of.....

The issue is not with your transmission tunnel, unless you are using a TKO tranny. The T5 will fit your transmission tunnel without modification. The issue is with the shifter opening on your transmission tunnel. It varries by car and transmission but in most cases, the shifter tunnel interferes with the complete movement of the actual shifter and you'll have to enlarge the opening. It usually only takes an inch or two to enlargen the hole; otherwise the T5 will fit fine. As I mentioned, if you are using a Tremec TKO 5 speed, then you will have to midify the actual tunnel because that transmission is larger. For your purposes I think you will be very happy with the T5.
 
Cool

I can modify the hole no problem, anybody want to buy a rebuilt c-4 with shift kit and stall convertor in the spring? LOL

I`m thinking this is gonna be alot better setup.

Today I got the carb dialed in a little closer, and changed the springs in the mechanical dist, and this thing will pin you to the seat now when i gas on it, and I know there is more hp in there I havent found yet.
 
There's a lot of people who talk down the T5 on the internet, but it's a nice shifting tranny for the money. Yeah it's not bullet proof. However, the blocker rings have that nice friction material on them which makes for really smooth shifts, and you can get a G Force rebuild kit for what, about $400? You can find a used T5 all day for $100 or even less.

The TKO parts are a lot more spendy. I'd like to buy a toploader from someone I trust, but eBay seems like rolling the dice. And you've got the external shift rails that people normally like to sell separately. :mad: Also the toploader has the same style brass blockers like the TKO. It just doesn't shift as nicely at higher rpms.
 
I'd like to buy a toploader from someone I trust, but eBay seems like rolling the dice. .

If you can get a Toploader for the same money as a T-5, it's not a crap shoot. Rebuild kits are less than $200 last I checked (David Kee's site) If you need to replace gears, that's another story, but not out of line with T-5 stuff. I bought my Toploader in the Ranger for $150 on ebay. The seller "mis-listed" it as an SROD:rlaugh: Got it with the SROD bell, & Hurst Comp + shifter included. He also had the clutch, pressure plate and flywheel included too, but I told him to keep all that, I wasn't going to use it anyway and didn't want to pay shipping on scrap metal. I resold the SROD bell back on ebay for what I paid in shipping ($80-- the SROD bell fits the Tremecs too). I bought two "broken" Toploaders for $150 locally and repaired each, then resold them for a profit later. All you got to do is wait for the right deal, same as everything else.:nice: If you can pickup a Toploader for less than $400, even if it needs repairs, it's still a good deal.
 
Ahh yeah, I forgot about the connector on the firewall. It'll have (4) holes for two circuits: one going to the backup lights, and the other circuit that goes to the neutral saftey switch on the C-4.

Off hand, without looking at the wires, or looking in the shop manual I don't remember which wires are what, but it would be simple to readout with an ohm meter to determine what goes where.

To bypass the neutral saftey switch for the manual transmission, all you would need are two .157" male bullet terminals and a very short piece of wire. Crimp the terminals onto each end of the short wire, and then plug the terminals into the firewall connector to complete the circuit. This will bypass the saftey switch that was on the C-4 --just be careful, 'cause now the car will start whether the transmission is in gear or not.

If you wanted to hook up the neutral saftey switch on the T-5, Run a wire from the firewall connector down to the switch on the T-5, then run a return wire from the other side of the tranny switch back to a switch mounted on the clutch pedal support. From the other side of the clutch switch contact, run a wire back to the firewall connector. This will complete the circuit, and the engine would only start then if the clutch pedal is pushed in.

You are really overthinking how to bypass the neutral safety switch. I did my bypass at the shifter by splicing the park and drive wires that attach to the shifter together and then I left it as-is under the carpet. The whole thing to me less than 5 minutes.
 
You are really overthinking how to bypass the neutral safety switch. I did my bypass at the shifter by splicing the park and drive wires that attach to the shifter together and then I left it as-is under the carpet. The whole thing to me less than 5 minutes.

You guys are overlooking the obvious (at least for a 65/66.) First of all, no splicing or special connectors are required in order to bypass the neutral safety switch.

Dash wiring harnesses are the same, whether stick or auto. When an automatic tranny was specified, there was a separate harness was added (the one that passes out to the engine compartment, via the firewall.) That short harness is plugged into the dash wiring harness.

You can disconnect this short harness and then plug the 2 remaining ends of the dash harness together to totally bypass the neutral safety switch, as was done with an original manual tranny car.

These ends are located above the defroster box and the ends are black. No other connectors on the car will look the same (they are the size of the bullets) and I believe that they are a "push and twist" locking design. Check it out.
 
If you can get a Toploader for the same money as a T-5, it's not a crap shoot. Rebuild kits are less than $200 last I checked (David Kee's site) If you need to replace gears, that's another story, but not out of line with T-5 stuff. I bought my Toploader in the Ranger for $150 on ebay. The seller "mis-listed" it as an SROD:rlaugh: Got it with the SROD bell, & Hurst Comp + shifter included. He also had the clutch, pressure plate and flywheel included too, but I told him to keep all that, I wasn't going to use it anyway and didn't want to pay shipping on scrap metal. I resold the SROD bell back on ebay for what I paid in shipping ($80-- the SROD bell fits the Tremecs too). I bought two "broken" Toploaders for $150 locally and repaired each, then resold them for a profit later. All you got to do is wait for the right deal, same as everything else.:nice: If you can pickup a Toploader for less than $400, even if it needs repairs, it's still a good deal.
You must be more fortunate or better at looking. T5s come up all the time for cheap; the last two I bought were $50 and $100, but every time I look for a toploader it's closer to $600 for something I have no idea how well it works and I'd have to pay to ship it across the country. I've never, ever found a toploader for sale locally. Not to say they aren't out there, but I've never seen one.
 
Doing the T5 was the best thing for my car, with 3.0 gears it dropped from 3K rpm @ 70 to 1800. Makes the car so much nicer to cruise on the highway. And as far as them being weak, mine is from my 88 which has 150K mi and was launched at 6K rpm on slicks over 100 times. Mine seems indestructable, didn't powershift and it's lived a long life. Swapped it out for TKO before I hurt it. I had to slightly trim the opening for the aftermarket shifter to clear. If you search, I think I posted pics of the modified hole