Antique & Classic Cars Blog
Weekend Tinkering
Sunday, October 21st, 2007With the sun out both weekend days, wrenchers trying to beat the winter took advantage. I stole a few hours to fix a gas leak from the carburetor and fix the custom shift linkage on my V8-in-a-TR6 project.
 Factory linkage for the TR8 gearbox puts the shifter back too far–note disassembled handbrake to make clearance. |
My friend Tom Porter, who rebuilt my ‘62 Olds F85 V8, is an ace fabricator and he and I figured out a way to take 6 inches out of the factory setup. The stock TR8 shift linkage uses a long shaft with heim joints on both ends. The bottom of the shift lever goes through one, and a pin at 90 degrees with the shaft protruding from the gearbox and which shifts it by going in and out and side to side, goes through the other.
 Factory linkage uses a shaft with heim joints at both ends. |
After shortening the aluminum housing by six inches, we didn’t have room for even one bracket for the shaft to pivot in. Instead Tom welded a heim joint to a forked piece of steel, welded a square bar to the base of the shift lever, and I drilled the fork and the square bar for a pin. The back portion of this setup pivots on only one axis, while the fork swings side to side with the shift lever. This allows the new shortened piece to be suspended without a braket in the aluminum housing and to still move the gearbox shaft in and out and side to side. It seemed slick and moved smoothly, but once fitted I couldn’t get reverse gear.
Inner weld was interfering with the heim joint, preventing it from swinging far enough to engage reverse.
|
Doh! The cause was some buildup from the weld, which I had overlooked. Once filed back to be flush with the housing, the shortened “remote,” as gearbox builder Rover calls the linkage, worked fine.
Shortened remote (top) positions shift lever six inches further forward than stock unit.
|
 |
 |
The forward placement is necessary to accommodate the stock trim piece, which surrounds the lever.
TR8 gearbox now has shift lever exactly where stock TR6 lever emerges.
|
Proper lever placement will allow the car’s interior to be indistinguishable from a stock TR6. Only the V8 engine note and much faster acceleration and top speed will distinguish this rodded ‘6 from a factory example–that is, until I throw in a Muncie four speed and NOS mid-’60s Hurst shifter.
Fuel leak fixed (for now) with JB Weld.
|
Made one further fix. The top of my Rochester 4GC carburetor had a hole near the fuel line fitting. Some piece may once have gone there long ago, or a factory plug fell out. I had drilled and tapped the hole and stuck in a plug, but fuel still seeped out. JB Weld made for a quick fix, but I won’t leave it that way. Although that stuff hardens like a rock, I don’t fully trust its purchase in this situation, where I’ve pushed a blob of it into a tapped hole. The hardened plug could, conceivably, pop out after sustained exposure to pressurized fuel. (Gas shooting on top of your hot engine is bad.) I have another 4GC so I’ll pirate the top from that one. A few fittings are different, but it’ll work. That project will likely turn up on these pages.
Keep tinkering.
7 Responses to "Weekend Tinkering"
Kris,
What a nice mod to the tranny! Seeing your comment about ultimately wanting a Muncie has me thinking a little. Don’t know if the TR6 is a 4 or 5 speed, but here’s what’s been going thru my mind.
Muncies are pretty expensive, and the wide ratios (a little preferable for the street I think are fairly rare. In the Vega I did, I used the stock 4 speed, a Saginaw. Not quite as butter smooth as the muncies are, but far more available and certainly should handle the 3.5, even with some modifications for power.
But, another issue is more interesting to me. I assume your TR6 is mostly for pleasure driving, not competition. Probably, the stock rear end gearing is fairly deep. The Muncie (or Saginaw) will give you a 60’s 70’s kind of car, turning relatively high RPM’s while cruising down the highway. It’s all in the lack of an overdrive top gear. When I drove vettes in the 70’s and 80’s I thought it was fine, but with “normal” gearing I was turning 2700-3000 at 60 mph. (3.73 and 4.11 gears, pretty common in them). Nowadays, things have changed. Normal highway speeds are up and I’ve gotten spoiled with V8 cars turning below 2000 RPM at 60mph. Easier to listen to, and much better mileage too.
Poked around a little on the net, and it looks like the old Monza variant had a 5 sp behind the 262 and 305 v8’s and it may have been a T5. Would a T5 be an option? Or how about the 5 sp’s that GM used in the small trucks? I don’t know what the options really are, but I’m sure you have time to do a little exploring. May be Forte’s http://www.fortesparts.com/
might be of help in looking at things, or D&D. Just some ideas.
Gary
Forgot…on the carb.
Unless that hole is actually in the fuel passage, (I am thinking it goes to the float chamber) it doesn’t see fuel under pressure, the pressure stops at the needle and seat, everything after that is atmospheric.
Carb: my fix is right at the fixture leading into the carb–it’s next to the fuel-line fitting.
There are several options on tranny and I appreciate your detailed feedback. I like the Muncie because it’s, well, a Muncie and that name has currency in the muscle car world. Also prefer it to the Saginaw (though my Hurst is, in fact, for a Saginaw-equipped ‘66 Chevelle–I’ll have to swap a piece or two of linkage.
Other options include, as you mention, the T5, a Tremec (more $$), the Supra tranny–compact and robust, or–and this is highly unlikely–a factory 4-speed Olds or Buick. They are very, very rare and didn’t even enjoy a good reputation.
My diff is about 3.0:1, I believe–nice with the Rover gears.
Under the Muncie dream scenario, I might even pull it apart to rebuild it, since this allows me to get a cheap up-front cost and have the fun of tearing it down. If I do that, I probably have some options on 4th. I could make it a little taller perhaps.
I hear you though…. I drove the stock 6-cylinder 4-speed configuration here from Philly and she sang at about 3,500 rpms the whole way. Though my wife loves, LOVES, the sound of a V8, I don’t need it going loud-mid-tenor every highway mile.
Kris
Here’s a little experiment for you Kris, now that the TR6 is on the road.
Muncies have a 2:20 (close ratio) or 2:56 (wide ratio) first gear. Find out what the ratios are on the rover tranny (that’s what is in there now?) and pick the closest one to the 2:20 and start out in that gear, that will give you an idea of what the close ratio would be like. Do the same for the 2:56. Don’t remember, if I ever knew what the Saginaws were like.
Don’t hold out too much hope of changing the muncie’s 4th gear, its a direct 1:1.00 running straight thru the tranny, no chance of modifying that, unless (insert wild idea here) you changed 3rd to a much higher gear and used 4th for 3rd and then you’d have a hell of a gap between 2nd and the new 3rd (4th) and probably end up cutting new gears…..aw hell, the tremec is looking cheaper by the minute.
In any case, here’s a web site I had stumbled across while looking at alternatives to the close ratio in my vette.
http://www.5speeds.com/muncie2.htm
Lots of good info on the original muncies, all of which are old, many abused. But go to the home page and there is a lot of info on other trannies, including a neat list of tag numbers and usages for the T5 and some surprised….82 S10 Blazers? Chevettes, Astro Vans? Cool
Hey, Kris just found your blog, It’s great to see you writing about the Triumph looks like your getting close to having a complete running drive speed monster. If there is anything we can do for you just give us a call.I would love it if you could email us some pictures of the car so we can post them on our website. take care Lee from Classic Iron Cars
You got it Lee. Readers should know that your shop handled the body and frame resto, plotted the engine location, built the motor and transmission mounts, massaged the firewall to get the bellhousing and new throttle linkage to work out, and re-routed the steering (put in u-joint) to get the shaft past the wider V8.
Classic Iron Cars also painted it Brooklands British Racing green, a color and paint job I get LOTS of compliments on. CIC also painted my ‘69 MGB GT (shown in various posts here), which also receives a lot of nice comments.
Where the build-up sits: She starts, runs, drives. I need to have an exhaust shop hang my TR6 dual exhaust system and make down pipes to connect it to the V8 manifolds. (I had Terry from TA’s Shell–who is a hot rodder and has been our mechanic for years for repairs I don’t take on–look at the pipes and tell me whether the diameter would work for a small V8. He said they were fine. Cool–starting with a TR6-based system should make for a good fit.) Once the exhaust is on, I’ll have Terry check the fuel/air mix and timing, then finish the interior–window channels, glass, trim, door handles, door panels, transmission tunnel, padding, Wilton English Wool carpet, couple other trim items, rear bumper, luggage rack.
I also need to have an auto electrics place check out my alternator. My wife wanted a high-end stereo so I put in an alternator with something like 78 amps. This charges the battery great, but it blows the fuse for the idiot light on the speedometer. Hopefully an auto-electrics specialist can tell me what to do to get that fixed. Will then get my classic radio fitted with modern innards.
Gotta get this machine on the road next summer–while gasoline is still on the market.
Gary,
Looks like the TR8 gearbox has a 3.32:1 first gear and a 2.09:1 second. Rear end is not 3.0 as I had guessed from memory somewhere, but 3.7:1 according to RimmerBrothers. That close ratio might be a little slow off the line. The wide ratio could be all right. Thanks for the Muncie info link. I had responded to that earlier, I thought, but it looks like that message didn’t post–probably user error on my end like closing out without hitting “submit.”
I like the aluminum case on the Muncies, but my Chevelle shifter is, in fact, for a Saginaw, so I could go that route. This idea isn’t dire urgent, so I’ll shop around for a bargain. If I find one, you can bet I’ll have the gearbox in my basement with the Hurst attached just to get my blood racing everytime I go down there.
Kris
Please leave a comment
MotorMouth Kris Palmer, freelance auto writer and editor, blogs about vintage cars, the collectible auto scene and just about anything else that goes vroom.
Your favorite: classic car blog, antique car blog, muscle car blog, vintage car blog. Antique and classic cars for sale by owner.
Have a collectible car to sell?
Try an enhanced classified listing for "Antiques, Classic & Customized" where you can upload photos of your vehicle, provide contact information, and filter through inquiries with ease. Sell your collectible classic online.
Subscribe to MotorMouth
Learn more about RSS
Blogroll
Categories
- Back to the 50s (15)
- Car parts (129)
- Car stories (168)
- Events (47)
- Motorcycle tales (23)
- Uncategorized (40)
Archives
Search Yellow Pages: