dados66

Hello all,

My '66 is in the midst of a frame-off restoration and I am converting it to a manual shift. It came originally with a Powerglide (and PB, PS, AC), which I am keeping, of course, but want driving to be more fun! It currently has a 3.70 rear gear and the engine will be a roller-cam 327 with 400-425 hp and side pipes.

I am evaluating Tremec TKO transmission kits from two suppliers--Silver Sport Transmissions and American Powertrain. I am also awaiting a quote from Hurst. The basic transmissions look to be the same, but the two companies (both located within 30 minutes of each other near Knoxville, TN) appear to offer slightly different shifter and clutch packages. The companies both quote similar numbers for the trans and install kit ($3700) but then some differences come in.

FYI I have already reviewed this thread. Found some great info there about the install but still wondering about kit comparisons (and service) from SST, AP and Hurst.

Shifters: The shifters both look like they have a rear-offset kink worked into the linkage but I have been unable to find anyone on forums that can compare the two shifters. They both say they are "bias-adjustable". And Hurst also has one called the Sidewinder II...?

Clutches: American Powertrain quotes $336 for a Science Friction clutch and Silver Sport quotes $166 for a "high-performance clutch kit".
Hurst offers one from LUK. I don't know how to make heads or tails out of any of them.

Finally, there is the Hydraulic Clutch Actuator System. AP included this $600 system in their quote and Silver Sport (which offers a Wilwood system on their website) didn't...is it necessary and what does it do? I am guessing it makes it easier since it's hydraulic linkage rather than mechanical?

Last question--anyone know much about the LGT700 option I have read about in a few places? No one seems to have much info on kits on their websites. How much more expensive would that option be and what advantages?

Many thanks!

Henry

65tripleblack

Faster shifting and brand new design. The TKO has gotten long in the tooth a long time ago. Some people complain that the SS/LGT700 is noisy, but with your sidepipes that won't be an issue. I have the "proven" RS600 in mine and I just loooooooove it!

Wise move using a roller. What are you using if you don't mind my asking?

dados66

Thanks for the input!

I am using a Howard's Cams hydraulic roller selected by the engine builder that has 0.510 intake and 0.530 exhaust lift. It will supposedly have a lopey idle similar to an L79. I don't know exactly which cam but the computer dyno specs he sent me matches their 110255-10 part number.

65tripleblack

In order to make that much power with such a mild cam, I assume that the builder is going to "breathe on" your heads, or replace them.

dados66

He implied it was a fairly aggressive cam...? Howards Cams describes the one with those specs as: "2200-5800 Rough idle, Street/Strip performance. Great low to mid-range torque & power". I will certainly clarify with him. The heads will be ported and fitted with 2.02/1.60 valves. He runs the dyno at Sonny's Racing Engines and has professional software for the power prediction so I haven't really questioned it.

65tripleblack

The specs show about 10 degrees more duration than the L79 @ .050" lift. Mild in terms of lift, however. But a good choice for the double humps, which are not capable of taking advantage of lifts much over .525". A very nice street cam and a good match to your heads.

I'm sure that they will install screw in rocker studs, open up the spring pockets, and drill out the pushrod guides. Do NOT have hardened exhaust seats installed. BE SURE that they unshroud the valves at the chamber walls after they install the larger valves. I recommend beehive valve springs, which will go easier on the valve seats. Comp Cams makes a set that was used on the LS1 engines and which should be sufficient with your cam. I can give you the P.N. and specs if you'd like. They will require a very MINIMAL opening up of the spring pockets to fit.

dados66

Thanks much! I know he mentioned unshrouding the valves and perhaps the other things but I will certainly check. There are alot of things I don't know about the tips and tricks of engine building which is why I left it to someone who does it every day!

GearheadJoe

I made this same swap several years ago using a TKO-600 from Kiesler. Overall I am very pleased with the results. Following are some responses to a few of your questions:

1) I just bought the clutch that Kiesler sold with their kit. This turned out to have more pedal pressure than I think some better clutches might have. So, I would recommend doing careful research on the clutch and possibly selecting one yourself rather than just getting the one that the vendor sells with their kit. I think the transmission vendors may feel some pressure to use inexpensive clutches to keep the total cost of their kit as low as possible.

2) There is no need to convert to a hydraulic clutch. The OEM clutch linkage will work fine with the proper bellhousing and throwout bearing.

3) If I were doing the conversion today I would be tempted to get the LGT700 because of the claims of better shifting. However, the truth is that I'm pretty happy with the TKO-600. I shift at 6000 rpm max, and the TKO syncros seem fine with that. However, I sometimes miss the 2-3 shift if I forget to simply "palm" the shifter, and I think that is a known aspect of the TKO that the LGT700 has improved upon. Also, I think the LGT700 has a synchronized reverse, which would be nice to have.

My TKO-600 is pretty quiet, and I'm not sure what to make of the discussions I've seen about noise with the LGT700.

I'm going to be doing an engine swap this winter, so the engine/transmission will be out of the car. I have considered using the opportunity to upgrade to the LGT700, but the stuff I have read about noise problems has me thinking I should just stick with what I have, because overall it works very well for my application (6000 rpm max). If you plan on shifting at more than 6000 rpm, the LGT700 might be a better overall match for your application.

MarkC

My thoughts are very similar to Joe's. I bought a TKO 600 from AP 3 1/2 years ago and have over 10,000 miles on it (1966 L79 with 3.70 gear). Last summer the pilot bearing went bad and it all had to come out. I went with Autogear's bronze bushing and I also installed a Luk clutch. When I put the TKO in I also installed AP's clutch. I liked the clutch buuuut, after the car got hot the clutch linkage felt like it needed grease. After it cooled off it was smooth again. This drove me crazy. I put a Luk in and it is very smooth and after driving in parades or long trips it is still very smooth. I think the problem was the AP pressure plate.

I do not race my car. I enjoy spirited driving and rarely get to 6000 r's. I do have side pipes btw. I have one complaint with the TKO from AP. The shifter is centered but it sits to high so with a shifter handle attached the rubber boot gets distorted. It doesn't look terrible but I doesn't look OEM. I think I saw not too long ago where Silver Sport has a lower profile shifter. That would make a difference for me if I was buying now.

The TKO 600 after it gets broken in is very smooth and with the bronze bushing is very easy to shift into reverse. When I had everything out this past summer I changed my cross member to "removeable". I have attached pictures. Since I have side pipes we used the holes in the cross member for the braces.

I love the Luk clutch. It is very smooth and easy to push in. I also love the gear ratios for the TKO 600. They line up perfect with a 3.70 gear.

dados66

Awesome feedback GearheadJoe and MarkC! I really appreciate it! I am currently leaning toward a kit from SST but may try to source clutch elsewhere. Shifter position is something I wouldn't have thought about until I got the trans without your post. Also leaning toward no hydraulic after reading your feedback. The LGT700 is unavailable currently from what I have gathered talking to a few people.

I also am going to sidepipes but want to avoid cutting the car, though that is a very clever removable mod you made, thanks for the pics!!!

GearheadJoe

Hi Mark:

Can you tell me the exact Luk setup you got? I want to start researching clutches so that I can change the clutch when the engine/trans come out this winter. I've pretty much decided to keep the TKO and change only the clutch.

rwerth7

I converted my 66 327 pg to the LGT700. I purchased the entire kit from Keisler b4 they went bk. I had initial problems with the trans due to assembly errors by Keisler. I worked directly with LGT and they assisted me more than I ever could expect.

Love the trans. Totally changed the character of the car. (Also had the engine rebuilt at the same time. Went with a roller cam that was fairly aggressive to get that "lopey" sound at idle but still drivable in the city.)
I have the off-road under car mufflers and the noise from the trans is not bad. My mechanic says it is quitter than the OEM 4-speed.

MarkC

I bought the Luk clutch kit from Napa. The Napa part number is 1104019. The kit comes with a powered metal throw out bearing which I did not use. I used a Federal Mogul part number N1488. This Luk kit gets you the 26 spline disc which I needed for the TKO.