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GT6 GT6 MK3 improvement possobilities [rotoflex]

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Flinkly

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ok, so i know there are a billion and one ways to improve our cars over stock, but since i'm getting into the mode of restoration where things go back together, what are my options for improvement for a rotoflex gt6?

i'd like to keep a reasonable gas mileage and don't want to change things that can't be undone. also, i'm not one for the super expensive bolt ons, such as most pri additions. example: i'd rather retrofit a set of toyota calipers like a tr6 than buy a special brake kit for 1500 from pri.

and if anyone knows where a wealth of info exists on just this topic, i'm quite interested, although i find more info on spits and tr6s than gt6s.
 
ok, to clarify, here are some things i'm going to improve already:

ignition - pertronix in dizzy
sound/looks - aluminum valve cover
exhaust - SS sport exhaust, without header (275!?!)
brakes - not sure how yet...but i will
guages - added oil pressure
headlights - hella headlights
wiring - powerblock, but i might need someone to really sell me on this one...
 
Sounds like you have a nice and mild resto-mod project gaining momentum! /ubbthreads/images/graemlins/hammer.gif

Canley Classics in the UK is a good place to surf for what is available off the shelf. Lots of alloy parts and finned/slotted brake rotors, brake servos, etc. The Triumph Sports Six Club has generated a lot of interest in those types of components. /ubbthreads/images/graemlins/england.gif

Spitbits lists quite a few, too, (like a dual temp/oil pressure gauge and headers) and they are certainly GT6-friendly. I admire their commitment to the Spitfire and GT6. /ubbthreads/images/graemlins/patriot.gif

There is a dedicated Triumph Spitfire website (and magazine) and you'll be able to decipher what is useful for the GT6 from their tech pages.

Good luck!! /ubbthreads/images/graemlins/cheers.gif
 
biggest driving improvement for a gt-6 is the long block change to a 2.5 l TR-6 engine!

not TOO complex...

basicly you must dress the tr-6 block as a GT, engine mounts, flywheel and balancer (something like 10lbs lighter on the gt) and the only real tricky part, the oil pan. My solution is to use the GT pan, but you must use a torch and dish the bottom of the pan where the counterweights of the tr crank swing.

You cant use the TR pan, its too deep and the drain hits the frame cross member. I guess you could change the cross member but thats altering the car...

power difference with the lighter GT flywheel and bigger displacement is considerable. Course you better consider how abusive it is to the tiny diff and transmission. You will have to use the GT tranny, something that was hard to come by and fragile even in my day.
 
Where's Andrew Mace?? Andrew, please chime in!

And, don't discount the 2 litre GT6 engine over the 2500 TR6 lump. The GT6 engine is a better balanced unit and will withstand higher RPMs. It's smoother. With the right mods, it can enjoy about the same HP as the 2500.

Also remember that once you get about roughly 150 HP, you'll have to modify other, key systems in order to withstand the extra power. The frame, drivetrain, brakes, etc., simply won't take much greater power.

And, I'll be the first to tell you that a GT6 with about 140 HP is a pretty fast mover. Unless you're racing ricers, more HP is overkill, IMHO.

Anyway, let's see what others have to say . . . and, good luck with your project!
 
[ QUOTE ]
Where's Andrew Mace?? Andrew, please chime in!...

[/ QUOTE ]Mark, funny you should use the words "chime in"; in another part of my life, I play an 11-bell (Troy) Meneely chime! But I digress....

I'd have to agree with Mark that there's no compelling reason to go with the 2.5L. He's absolutely right about the shorter-stroke 2L. And there's a ton of stuff you can do with it if you so desire.

If you do go with a 2.5L, you might as well grab at least a TR gearbox to go behind it. It CAN be made to fit and will last longer than will the stock GT6 gearbox. Then there's the diff; you'll probably have to do something there as well. Oh, and then better brakes WILL be a necessity, etc., etc.!

It's been a long time now, but in an earlier life I lived 24/7/365 with a 1970 GT6+ that I'd bought with only 20k and five years behind it. (After about two years, I did also pick up an old Volvo to relieve the GT6 of hapless winter driving 1. because it was already starting to rust badly and 2. because, frankly, the GT6 was NOT a great car to drive in snow. AGAIN I digress; sorry.)

Anyway, that GT6 went through just about anything and everything with me, including daily commuting, occasional vacation trips, and a whole bunch of road rallyes and autocrosses. Through all that, the greatest and only deviations from stock were 175/70R13s instead of the 155SR13s that would've been original (and the A78-13 bias plies that the PO had shamed the car with just before I bought it; fortunately a friend with a Pinto really wanted those tires, and I was happy to oblige) and a set of Koni shocks all around. The car was virtually always reliable, and it was a fine performer in every respect. It was comfortable enough that the ride impressed a Buick-owning non-car-guy neighbor of mine, but capable enough that I took my share of class wins in local autocrosses (even a couple fastest time of day trophies).

What I'm really getting at here is pretty much the same point I often end up making to new Herald owners, many of whom have the the notion that, just because their other car has 375 hp and every other gimmick and option short of a cappucino maker, their Herald MUST need instant and massive upgrades -- even though they've yet to even start it, let alone drive it any distance! My advice to those folks, and to you, is to start by getting what you have in the best possible condition. If what you end up with isn't to your satisfaction, then go S-L-O-W-L-Y with upgrades, and start with the "classics" such as wheels/tires; upgraded ignition, porting/polishing -- some of which are already on your list.

Oh, I did have a "sport" exhaust on mine at one point. It sounded ok, but the most noticeable change was the slow but sure creation of a flat-black rear valence (and license plate and lights....)

One other point of reference. Several years after parking that 6+ in hopes of an eventual restoration (I'm still hoping, 25 years later), I picked up a cheap and somewhat bedraggled, but mechanically sound '72 GT6 Mk3. For "lifestyle" reasons only, it didn't see the competitive motorsports events that the 6+ had seen, but it saw plenty of road use. Even though it had the "Federal" low-compression engine with only 79hp (compared to the 95 of the 6+), I never felt a great loss by comparison.

And earlier this summer, I went and test-drove another 70 GT6+ that a friend was anxious to buy. After brief drives by both of us, he very quickly negotiated a deal. What a rush it was to drive one again! It might only be 95 hp, but the torque is amazing...and so smooth.

So get it running well, enjoy it awhile, and THEN see if you really think you need to drop thousands into upgrades that might (or might not) yield some benefit. Triumph really did a pretty fine job of presenting a nicely balanced tourer in the GT6!
 
thanks andrew, i am headed in that direction, but i have upgraded some things since replacements were necessary anyways, but i'll try to rebuild her to spec as much as possible.

i am really leaning to a sports exhaust if only for the better look... /ubbthreads/images/graemlins/grin.gif

i am gonna upgrade the wiring if that would be the best choice in the long run. it needs to be replaced asap and an upgrade there seems intelligent to me. as far as the pertronix dizzy, i'm going to have Mr advanced distributor make me a top for points for backup and a pertronix top, so i can start with points and upgrade from there.
 
Mark and Andy, good stuff!!! /ubbthreads/images/graemlins/smile.gif

Flinkly,

Two more thoughts:

Another way to look at your project is to take a look at Kas Kastner's Competition Manual for the GT6 and see what period-authentic modifications you could attempt. His three recent books should also help as well.

At the Coventry Transport Museum, there is a GT6 Mk3 in the collection. It was a modernized car to say the least. Anti-chip paint on the rockers and valences. Flat halogen headlights. A Webasto sunroof. A rear-window wiper. Additional gauges. Spax shocks all around. There's more, but that is all I can remember without digging out my pictures. I really liked that the car was obviously an expression of the owner who restored the car to drive it in the "modern" day and not a period-correct restoration.

I agree with Andy and Mark. There is nothing wrong with a stock GT6 (lately I've been tempted to start a thread in defense of the GT6) and you are going to have fun improving the basic package as you have already stated.

Be sure to let us know what you decide to do. I am compiling my own list of improvements for the time when my GT6 restoration regains momentum.

/ubbthreads/images/graemlins/cheers.gif
 
[ QUOTE ]
At the Coventry Transport Museum, there is a GT6 Mk3 in the collection.

[/ QUOTE ]

What a great place yah! Do they still have the 'Bombing experience' section? I was there with a group from my local car club and we were given quite the extensive tour and allowed to actually sit in many cars that weren't on the floor. Of course a lot of people did have photos taken in one of the Quenn Mum's Daimlers. Neat place!

/ubbthreads/images/graemlins/cheers.gif
 
[ QUOTE ]
Yep, the Blitz exhibit is still there. Seeing that and then making the short walk to the cathedral really illustrates what Coventry went through during World War II.

[/ QUOTE ]

Did that too. Powerful stuff. The only church we visited the entire trip. /ubbthreads/images/graemlins/wink.gif
 
[ QUOTE ]
...(lately I've been tempted to start a thread in defense of the GT6)....

[/ QUOTE ]Well, it's a car that seems to have needed some defending right from the very start. More importantly, the GT6 long "enjoyed" notoriety (think Rodney Dangerfield) as a neglected and sometimes almost forgotten car, right up there with the Herald and TR4.

Like every other car ever produced, much of it is a matter of personal taste. To me, the GT6 is one of the prettiest shapes ever developed for a sporting car...yes, even the earlier ones with their seemingly endless supply of proprietary Lucas lamps tacked all over the rear end! (Honestly, the 1970 "Federal" model, worst of all in the lamp and reflector department, is my all-time favorite!) And any Triumph six is something that any car guy/gal likely would've fallen in love with from the very first drive, be it the 1.6L Vitesse/Sports 6 version, the TR's 2.5L version or the GT6/2000 sedan 2L version. So smooth and so torquey; what more does one need? /ubbthreads/images/graemlins/grin.gif

Fortunately for all of us, GT6s are being rediscovered and appreciated, just as are TR4s and Heralds, for the unique and still very enjoyable and useful cars they are!
 
I agree totally with the others here that the GT6 is a blast to drive. I also agree with those with concerns with the strength of the transmission and diff. I rebuilt the trans twice and the diff once. I also had a problem on mine with the clutch slipping instead of the tires breaking loose. After a couple of times replacing the clutch and pressure plate I gave up and did not tend to do hole shots. That probably saved the drive line from more problems.
I drove mine for the first 55k or so of it's life and considering the almost constant position of the loud pedal being on the floor it was a quite durable vehicle. It was my only transportation and I was very satisfied with every aspect of it. Exception being that I missed my previous car, a TR4, with the top down.

Just my opinion, but, the original high reving engine made the car. I would never replace it with a 2.5l TR6 engine.
 
2 litre for race engine, 2.5 for torquey road car, gearbox can be blueprinted( or swapped for rover,ford,or supra),lsd diffs are okay mostley, 3.63 ratio. rotoflex shafts are about as much good as a cat flap on a submarine,can replace with steve smiths bullet proof special shafts,or tony lindsey deans(also does excellant g'boxes)660lb springs front,(i use 900,2.5 spit)and consider avo shocks,SORTED. /ubbthreads/images/graemlins/cheers.gif
 
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