Tom_K

Is there really any difference to the Tremec 5 Speed trans upgrade kits offered by SST or American Powertrain?
Is one better than the other?
I have a 68 427 car with a 411 rear that really need the overdrive.

My plan is to do the swap and keep all original parts as it is a matching number car.
From what I understand the kit and trans can be installed without any permanent modification to the car. (It can be undone)

Thoughts?

cagotzmann

The kits will vary.
1. shifter used (factory or modified shifter mounting)
2. hydraulic TOB
3. Cross Member style (how exhaust routes etc)
4.. Clutch kits

So I would examine each item a select the vendor that gives you the best support.

When I install my T56 Magnum 6-speed, no kits where available so I used parts from many vendors, shifter & TOB from American powertrain, drive shaft etc.
All I can say is my experience with American Powertrain was not the best. The shifter (whiteligthning) leaked. They first sent a wrong shifter, then the replacement still leaked, they had no solutions, I showed them the design flaw for the T56 design, I ended up settling by them sending me seals so I could modify the design. I had no other problem with the parts they supplied. Being in Canada its difficult to get good support from USA vendors due to return shipping cost / border costs etc.

Now the TKO units are not the same and may not have similar problems but at the time for me there were not a lot of choices. SST was not in business. So check out the kits in detail.

BLUE1972

I have installed both kit s helping friends. I chose the SST kit for my car and I prefer the SST - Silver Sport kit as it is direct fit and the driveshaft is a perfect fit. I also like the "Corvette " shifter.

Their Tech department is fantastic and you do get a call back when they are busy.....

Call SST and talk to them, they are really helpful.

A hint. If you lift the motor move it forward a few inches the install gets real easy.

OldCarBum

I just received my SST auto to manual conversion kit with the close ratio TKO-600 5 speed.
SST was great and all the parts are top quality.
Give them a call you will be satisfied.

Gordonm

They all start out with the same trans from Tremec. It is what they do with it from there that puts some ahead of others. I have installed a dozen or so kits. I personally like the ones from SST and their customer service is excellent.

CheezMoe

I went with Hurst Drivelines and they were great. The reason was I like their sidewinder shifter. It positions perfectly in the factory location and allows an assortment of handles and shifts smooth as silk.

BLUE1972

the SST kit puts the shifter dead center in the factory opening .

I've had 4 or 5 C3 owners try to move the car and they didn't realize it was a 5 speed - they thought it was a stock 4 speed.

Some day I will change the shift plate to the 5 speed plate …….

Capt. Shark

I am seriously considering this as a winter project. I've talked to the tech folks at SST several times now and they have been very helpful. I will definitely use their products if I do the swap.

Kie

scottjamison

The SST kit is perfect. (Well named). So easy to install too. I did mine with my 496 last winter and have loved it.
I went with the hydraulic TOB and pedal with the dual disc McLeod clutch and it is super nice.

jim-81

I also went with SST for my TKO600. All around great project. SST was great to do business with, all parts are labelled, bagged, cross member was beefy, they even sent me another speedo gear when the first one was not quite correct. Recommend.

scottjamison

Some recommendations for putting in the SST system:
1. I had trouble routing the speedo cable and chewed up the first one. I got one of the 90 degree joints and put it on at the trans. It works great.
2. The bolts on the top of the trans are a little hard to get your hands into once it is installed. IF you can install it with the shifter tower attached it will be easier.
3. Make sure to tighten the little screws for the shifter cover well before install if you can. It is a PITA to do it afterward especially if your exhaust is already installed. It is possible. Just a little knuckle knocking.
4. The shifter **** DOES unscrew to put on the rubber boot. Mine was so tight I thought it didn't come off. I didn't realize until after I squeezed on the boot from the bottom that it did indeed come off.

All in all a super easy install with 2 people. But I did drop mine in with the motor attached.

Capt. Shark

I'm on the fence about the hydraulic clutch. Motor was out for rebuild two winters ago and it was replaced then. Works fine and not nearly so stiff as the original. SST said there was no real need to do it since it's a new clutch. Adds about another $1000 to the project. Still haven't decided for sure, though.

Gordonm

I have had the stock linkage then upgraded to linkage with Heim joints and now have a hydraulic TOB. The reason I went with hyd is that the T56 I am using has the TOB mounted to the front of the trans and it was all packaged nicely. The stock stuff in good shape works just fine. The Heim jointed linkage is a nice upgrade. It makes the pedal smoother operation. No difference in amount of "leg torque" needed to depress the clutch. The hyd setup will reduce the amount of "leg torque" and is seamless in operation but as you said is pricey and requires a bit more install time. I have installed many 5 speeds and done quite a few of each and they all do the same thing. They release the clutch. Its up to you on how seamless you want the action.

CheezMoe

I did a stock style clutch with a heim joint linkage kit and a dual friction clutch. Action is very smooth with about 1/2 the leg torque of a completely stock setup.

Capt. Shark

Metalhead140

I rebuilt all the pivot points in my standard linkage, work great with my tko600. I used the mount, shifter handle, console plate and a couple of other small parts from Hurst, but used a standard box and shifter which I modified to suit, to avoid paying shipping and import costs on the whole kit (bought the box here in Australia). I certainly found Hurst helpful in being willing to sell me individual parts, and was very happy with the quality of the parts that I purchased, but can't talk to their full kit.

Priya

By not so stiff as the original are you saying that the clutch pedal takes a lot less effort to push in?

Capt. Shark

Yes, a noticeable difference.

Capt. Shark

Looking at the specs for the 5 speed, these are the gear ratios.
TKO 500 - 3.27, 1.98, 1.34, 1.00, 0.68
3.27 1st? I think my stock 4 speed is 2.88 1st gear and 1.74 2nd so a little taller gearing.
I did calculate, though, that 80 mph in 5th gear is 2500 rpm and my stock 4th gear is 3700 rpm. Significant difference.