I went with a set of Sanderson short tube headers on my 73 BB.
My research was based from telephone calls to Hooker, Hedman and Sanderson who all told me basically the same thing and that was short tube headers will develop more torque and horsepower below 3500 rpm which is where most street cars are operated. They are typically equal from 3500 to 5500 rpm and long tube headers will produce more horsepower above 5500 rpm.
I'm sure some will argue but that's what they told me and Sanderson provided dyno test run sheets on their website.
I was also concerned about fitment with my Borgenson box and they said they will clear.
My other concern was with ground to tube clearance which will not be reduced with the short tube headers.
I'm converting from a TH400 to a TKO6-- and am saving my pennies for the Silver Sport kit which everyone raves about for parts and ease of installation.

 

Thanks for the input. I was also of the understanding that short tubes will help low end torque....but clearly there will be differences of opinion, which is great. It makes us all do more research.
I'm prob going to start on the auto to manual conversion in mid April. I'll keep you posted on how it goes.

 

Ask your mechanic if he has dialed in a bell housing. I made a custom mod to a magnetic dial indicator base to speed up dial in time

my advice is to buy Allen locking bell housing guide pins of a couple sizes and just return what you don't use

I use roller pilot bearings. The reality is, if your bell housingis less than. 002 out the tranny input shaft should never touch the pilot bearing. So you can install a bronze bushing. Have the person take pictures of the dial indicator as proof of under .002 at 3,6,9, and 12

 

This is great advise and sounds almost excatly what my speed/machine shop is advising.

 

Another thing to keep in mind is if you are going to run the wide ratio (.64) or close ratio (.82) TKO, and what your rear end ratio will be.
I'm planning to run the close ratio (.82) with 3.08 rear gears, because my cruising rpm @ 70 will be around 2100 rpm which will work perfect with my hydraulic roller camshaft with it's operating range of 2000 - 5800 rpm.
Do your research and plan what works best for you and how you plan to drive your car.

 

I looked through my drawer and the name of the locking dowel pins are Lakewood from summit racing. I've also used stock type offset and the extended length dowel pins over the years. You can use stock pins, but even with honing the block hole and grease they become hard to rotate when partially tapped into place. I fought them for years until the locking dowel pins came out. Time is money.

What the problem is: The factory is mas producing with an error margin. Then you now have blocks that with time warp and shift. So the center of the bell housing output hole is not on center with the crankshaft pilot bearing center.

If you buy a painted aftermarket bell housing. Buy a 200 or 400 grit flapper type sanding tip for a drill. Remove all the paint from the inside of the bell housing tranny hole. You will never get a good dial reading on the variable thickness painted surface and the tranny might be very tight fitting.

I actually learned things every time I had to dial in a new bell housing. I even dialed in manual bell housings and then installed racing automatics to ensure that they were centered.

 

Thank you very much for your input.
The experience and wisdom on this forum continues to amaze me.

I may not been clear on my planned transmission path. My plan is to go with the Tremec TKO 5 speed with automatic to manual conversion kit from Silver Sport Transmission. I just got off the phone with a tech from SS and he claims that everything I need for the installation and mating to the SP383 is included in the package (see attached).
I'm going with the hyrdraulic clutch. Apparently no modifications to cross member are required other than installing a bracket.
He stated the most challenging part will be installation of the pedal. It's my understanding that the C3 firewall on automatics has a plate covering an opening designed for the clutch pedal on manuals. With the engine out, I dont expect too many issues.

I definitely appreciate the input on dialing in a bell housing. Any additional input on components and potential pitfalls are appreciated.

Thanks again.

 

I have the tranny adapter like that from Kiesler (sp?) on an install. The tail shaft on a TKO is longer than a TH 350/400. Just use a wheel cutter or plasma cutter on the cross X. and then weld the new mount on. I originally had the stock L82 mechanical fan and shroud with the AC electric fan

modern telephones ... just down load the app for the degree balance level. with the motor and tranny installed and floor jack under the rear of the tranny align the tail shaft left and right to near Zero. Then set the down angle on the drive shaft to @ 2.5 degrees. You then have to make a spacer block to from the mount height to the tail shaft.

When I first did mine in the Vette Nobody told me what to do. I was off and I had a high speed buzz through the shifter handle cruising down the road at say 70 - 80 mph. I thought that maybe my new drive shaft was out of balance. I had made it a perfectly straight shot because I had an aluminum block differential snubber and solid mount differential cross member. Somebody told me about using an angle back then. the angle apparently is required to make it balanced.

I have solid motor mounts and a solid block for the tail shaft. I have a happy high rpm tko 600 very well tested.

I driven around for over 20 years and 100,000 miles with 4.11 rear end with OD 700r4 and tko with .64 OD. With big enough motors it gives you the ability to push the go pedal even in OD . lower rpm motors I would still recommend a 3.73 or 3.90 rear with a tko 600

On my vette I had the engine in and had to remove the vacuum brake canister to mount the clutch rod assembly. The Keisler kit Z bar had a couple of mounting holes. I drilled a lower mounting point for the shaft increasing the throw out bearing movement. So the clutch disengages with less pedal movement...... you only have a couple of inches from in and out. NO pushing the clutch pedal to the floor. My Sparco fiber racing seat is mounted to the floor and back against the battery box so my legs are nearly straight and it gave me more helmet room to the roll cage and roof

 

 

I read your silver state quote. It says light pedal effort clutch. You can save $649.95 and $21.95. By not getting the hydraulic clutch

it also says 168 tooth fly wheel. So you need to buy a gear reduction mini starter. This is one of the best and mine is 17 years old

https://www.summitracing.com/parts/sum-820323-m/overview/

 

Here is my 78 auto to manual 6-speed conversion. GM ZZ383 motor with T56 Magnum 6-speed. This was before anyone made any 6-speed kits.

The only change since the original install, I replaced the single disc clutch with a twin disc, and light alum flywheel. The single disc was to heavy for me. I have been driving C6 corvettes for many years at the track and I use my 78 for track days, so the change to the twin disc made it very close to the C6 feel.

Here are my notes on the install.

https://www.corvetteforum.com/forums...-corvette.html

 

Youre the man! Thank you for the starter recommendation.
I'm still debating hyrdraulic vs mechanical clutch. As this is my first go round with this type of thing (as is probably very evident) I'm leaning toward minimizing fitment issues and focusing on ease of installation. I'm also trying to consider interference and fitment for future upgrades that I might consider.
This points in the direction of hydraulic, however, to your point, the cost isnt insignificant.

 

Thank you.
I read this post yesterday. You did an amazing job, and your car is awesome.

 

My first thought was like your's and I was planning the hydraulic clutch as well. After reading and doing my own research I've decided to go with the dual disk clutch due to fitment issues.
I'm not sure about sbc's but the later BB's do not have the setup in the block casting for the manual clutch.
If its the same thing on a sbc then make sure your 383's block casting will except the linkage.

 

I have that same kit from SST. While I still have to put the pedals in, everything and I mean everything is in the kit. I may still run into problems putting the pedals in the car, but so far all the parts have been in the kit and have been high quality. Definitely recommended.


I did have to fab up a couple of tabs for the crossmember bracket. The auto crossmember is missing the tabs, or at least mine was. Other than that it has been a complete bolt in kit.

 

Did Silver State buy kieslers inventory and start over? If they did I would ask if they still have the Sachs Clutch and PP assembly. I'm not sure what the one on your list is. I've been using it on my two engines for years. If they don't have the Sachs you should upgrade to the

https://shiftsst.com/store/clutches/...lutch-kit.html

I opted for a Lakewood red blow proof bell housing. The Black non SFI is a good safety item over any aluminum bell housing.

 

I used a gear reduction starter from a 1996 Chevy full size 4WD truck. Its been working perfectly for 20 years. Less than half the cost of the Summit piece.