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TR6 Newbie looking for hopup guidance

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steveg

steveg

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Hello Triumphants!

I'm the new owner of a '74 TR6. I live in California and my car doesn't have to be smogged. So am looking for guidance about setting it up as if it were 10 years older. For instance, what does one do with the retard distributor? Can it be made normal?

Has anyone written a book or a paper on some of the easy things to do.

I have a decent budget, but first want to make the car run properly before getting inside the engine.

I'm a 20 year Healey owner and active on the Healey Forum.

screenshot.2317.jpg
 
Welcome S. I am new to this site also but have owned my TR 6 1973 for 25 plus years. Yes there are some changes you can make. As you have a 74 it lost some HP from the factory as the US went Smog heavy. Some might tell you to change your carbs a % here and there, add one to trip carbs if you stay near the coast and not above 4,000 feet or you start losing power. I live in Reno 4,500 feet and at the coast I run much stronger. As for the distributor change to electronic and hot coil. Note make sure your distributer is in good shape you may need new plate and weight assy and bearing. An easy one is a heat shield for the carbs K&N filters and more outside air to carbs from around radiator. Mallory distributer and change Tac. as there is no drive. Spark, Air, fuel and better tires change exhaust flow they say 10% but not headers You can read more about that here . If you want a road car as mine is overdrive and cam down the line. As for your AH some say the TR 6 has better reviews and you will not have the heat in the car as you do in the AH they are fine LBC's and who can live with out two LBC's any way. Madflyer
 
There will be a nipple on the bottom of a 74 front carb that supplies vacuum to the distributor vacuum retard module as well as supplying vacuum to the Throttle Bypass Valve...all those vacuum lines meet up at the Thermostatic Vacuum Switch situated in the top readiator hose.
If you decide to disable all that, just be sure to TIGHTLY seal off the vacuum source...the nipple on the bottom of the front carb...Do that and you can remove all the associated vacuum, (but not necessarily the emission control) lines...no need to close their nipples other than to exclude dust.
What I described is the original, as left the factory, vacuum plumbing with Zenith Stromberg carbs..whether it's still like that after all these years, only you can tell at this point, but maybe these illustrations will help.
https://mossmotors.com/triumph-tr6-250/fuel-intake-emissions
However, except for the retard effect when the engine is idleing....none of the plumbing has a negative effect on performance.
The Throttle Bypass Valves will act up with age and affect the quality and stability of the idle...that's something to note
And because tampering with Emission Stuff may be considered illegal by some, I doubt if you'll find a publication expalining how to do such...but plenty of us learned and know even if by trial and error... If you remove something and the engine reacts badly there may or may not be some form of compensation...that generally does not apply to carburettor adjustments though....they have certain components that don't age well and need periodic replacement, not readjustment of the visible screws.
Good Luck and don't be afraid to experiment.
 
You could get the Competition manual
https://www.amazon.com/Triumph-Competition-Preparation-Manual-TR250/dp/1783180013
Extract what you want from that, but I think one of the first things you might want to do is have the head shaved to increase the Compression Ratio, then give the engine and carbs a good tune-up...after that the world of aftermarket parts opens to you...but you'll still have a TR6 as long as you have the TR6 engine....
 
Agree about shaving the head. If you want to go a little farther a mild cam, exhaust and lightened flywheel will perk things up a little more. You can get 20 or so more hp pretty cheaply and easily, and it will make a noticeable difference with very little downside. Would also recommend an upgraded front and added rear sway bar.
 
Check your shocks carefully. If they're not working as they should, it will negatively affect your ride and handling. I just replaced my fronts and they made a big difference. One of them was frozen. I also installed tube shocks on the rear but some claim that's a bad idea. Check your differential mounts carefully as well. They've been known to crack. They can be boxed in and welded. I think we'd be interested in how your TR6 compares with the Healey that you've had for so long.
 
glemon said:
.

I 2nd the motion
Click to expand...

OK, but I just got the car last Friday and it's in the shop replacing the starter and a bad rear u-joint.

Will reply later on after I've had a chance to fix some things and put some miles on it. Gonna be apples-to-oranges, I think.

The TR6 is certainly going to be more comfortable with a better ride. Healey a good deal faster - we'll see what can be done to pep up the '74 TR6s low-compression engine.

More later.
 
It likely goes without saying but if this car is new to you, make sure the brakes are functioning properly before you make it faster...
Good luck, I’ll be watching with interest as I’d like to do the same to mine!
c74
 
glemon said:
Agree about shaving the head. If you want to go a little farther a mild cam, exhaust and lightened flywheel will perk things up a little more. You can get 20 or so more hp pretty cheaply and easily, and it will make a noticeable difference with very little downside. Would also recommend an upgraded front and added rear sway bar.
Click to expand...

I see Good Parts has a 278 degree cam. I have a 278 degree Denis Welch cam in my Healey and swear by it. Hotter than stock, but still plenty of grunt.

PS - I ordered the Good Parts throttle rod bushing set which looks to be super-easy to install compared to the stock setup:

screenshot.2316.jpg


I'm enjoying this - there's a lot more accessory and speed equipment available for the TR6 than the Healey!
 
Unless it is malfunctioning, none of the emissions equipment reduces performance. Still, many remove it just to eliminate complexity and failure points.

As for mods, upping compression to 9.5 or so, and adding a GP2 or equivalent cam will give you a very nice street machine.

Love to see a pic of the TR and Healy together.

Ed
 
Good call on the throttle rod bushing, I don't call uncle on many things, but after spending the better part of a day and slicing them down to the point they were almost worthless I gave up and rigged up my own setup.

And yes there is a lot bigger selection of aftermarket go faster bits, Rimmer Brothers and British Parts Northwest are good sources, plus lots of specialty shops.
 
The IRS on the TR6 can be troublesome and very strange. For example, for many years my steering wheel was not centered when the wheels were straight ahead. I thought it might have been installed incorrectly, but I found out that with a piece of string and some shims on the right rear trailing arm, we were able to straighten out the steering wheel. Check the rear hubs carefully. If they're loose, it could be dangerous. Also use a torque wrench when tightening the hub nuts. Overtighten and you can strip them. Leave them loose - they can work loose and you lose a wheel. Not something you want to happen. Electronic ignition? I tried it, almost conked out on a hot August day, sent it back to Crane, they said it checked out perfectly, re-installed it, almost conked out again on a hot day, took it off and re-installed the points and had no further trouble for the last 10 years or so. Some owners switch to Webers - two or even three I've seen, but I can't comment on that. You'd have to post a question or go to a meet where these cars show up. Some owners install a rear sway bar. I didn't. These are very reliable cars that suffer more from owners who won't leave them alone, incompetent mechanics and DPOs who cobble them up and leave you a mess. As an experienced LBC owner of a similar car, I guess by now you know what these cars are like. I've read and heard that Healey's develop a lot of cockpit heat but you won't get that on a TR6. Good luck with your new purchase, Steve, and be sure to let us know the comparison with the Healey.
 
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