1969 Triumph Spitfire Mk3: Long term re-build 4AGE

[krissto]

Hello,
Here starts a really long story of my Triumph Spitfire Mk3 rebuild.  It started as a restoration (circa 1988) and rapidly morphed into a total rebuild and re-engineering of this car.  So let's start with some ancient photos and a brief history.  Please bear with me while I get used to publicising this rebuild on a new (to me) experience of writing a blog...

The car was bought, by my late Father, I think in 1972. At that time it was a dark blue colour with wire wheels and a factory hardtop option.  I was a mere 8 year old, but already a car fanatic and fan of motorsport.  Here is a dusty/cropped image of (I think year 1974) at the family home:
 


We then jump a few years to 1977 after Dad had resprayed the car in Mimosa yellow. 



How about those outrageous balloon tyres?  So seventies....  More updates to follow soon.

Thanks,

Chris

[biturbo228]

Aha I was hoping you'd post up a thread after you mentioned it on Darkspeed's thread. In for the ride!

[glenanderson]

I do like a Mk3. Very fond memories of being exhilarated and terrified in equal measures travelling to work in the passenger seat of my mate Rich’s one in the mid/late 80s.

[jimi]

4A-GE ? More info please

[hagus]

As the owner of a 1972 spit my parents bought new the year before I was born this is right up my street!

[ferny]

This'll be interesting because this was my initial plan with the Herald but opted out when looking into transmissions. I switched to Zetec but again, what needs to be bolted to the engine didn't work for me. In the end I went Mazda as at the time I knew of only two Mazda powered Triumphs, I could take advantage of the money they'd spent on R&D and didn't want to modify the chassis for fear of losing the registration.

The gearbox you use will be the most interesting bit for me. My only real experience is watching Nick Jones have a play and I didnt want to repeat any of his pain!

[vitesseefi]

Good to see a MK3 getting some love.....

My pain?

Was that my Toyota pain (W58 to Triumph 6), years ago but still working fine, or my current Mazda pain?

The natural partner for the 4AGE is the T50. That should go in without too much aggro seeing as it should already fit the engine. Biggest challenge will likely be getting hold of one without selling a kidney.

It has been done before, though more often in the US or Antipodes where the donors are more readily available.

Believe some care is needed with engine selection as some later FWD ones may lack the drilling for a spigot bearing in the end of the crank.

MX5 is an easy win availability-wise but the long box and very rearward shift position brings challenges. Don’t remember how you overcame those in your Herald Pete?

Nick

[ferny]

When I saw the size of the boxes you were playing with I was happy to nope out of doing something which might need the use of a brain! 😂 Plus the Toyota stuff seems pricey, as you say.

For mine, I shortened the remote and made use of the holes further forward. My engine is behind the steering rack which meant the bulkhead needed 2-3" taking out, but moving the remote forward (I think) 7" made the gearstick sit near enough to the original location. It's an earlier gearbox so I don't think it's an option for you. I'd like to go 6-speed as they're stronger but it's the same issue.

[krissto]

So now we jump a few years to Winter 1981 and the poor Spitfire was diagnosed, by my Father, to have rotten sills and rear wings.  It sits here with a covering of snow, but at least the doors have been left in place to avoid door gap collapse.
 


Then we fast forward onto 1982 and he's (arc!) welded new sills, wings and other repairs and partially repainted it again (the same Mimosa yellow).  It now has a Richard Grant deep front spoiler, which looked okay from some angles, but too OTT from others.  He worked in Switzerland in those days, so the car lived over there for a while.  Pictures from there, with the Zurich-See in the background...












The panel fit was not great and the rear spring was on its way out, but I think it looked pretty cool - somehow different from many other Spitfires at that time.  I was only 18 back then and was so proud of that car - and probably biased.

Quick 'spoiier alert' for the future.  The car now has a Toyota Corolla AE86 16V (blue top) 4AGE engine mated to a T50 gearbox.  Lots more of that to come in later posts...


Thanks,
Chris

[krissto]

The Spitfire came back to the UK a few years later (mid 80's) and here's a shot back at the family home, all iced up.  Still looking ok-ish at this point but the car needed some TLC that would not be practical in Switzerland...



While back in Blighty, it had to lose the wire wheels as they were beyond repair in terms of spline wear on the wheels and adaptors and being out of round.  If my memory serves me right, during this 'visit', the rear spring was replaced with a swing-spring, the overdrive updated to a J type and the wheels changed to steel slot mags.  The exhaust system was converted to a twin box at the rear (Father's own design) and then went back to Switzerland once more.   A little later a change of job for Father meant that he would be pretty much permanently resident in Switzerland, so the car came back to the UK for the family to look after.  By this time the ravages of Swiss winters had taken effect...



As can be seen in the above, there's some rot appearing on the door lower , bonnet, rear wheel arches etc.   So I tried to attack the rust (1986-1987) , with cosmetic repairs, but I knew it would not last...



The next instalment will detail the horrors that I encountered when I took the car off the road for bodywork restoration .  It will be all too familiar to you Triumph owners in this forum...

Thanks,
Chris

[krissto]

We now arrive at 1987/88 where the car got too tatty to continue using.  So I took it off the road and started to attack the rot.  The following pictures only show part of the woes.  Remember that the car had received new sills, rear wings etc., only a few years previous.  It just goes to show how important it is to rust-proof a car after rebuild - and not use it all seasons.  Can't really blame my Dad for this as he just wanted to enjoy driving.





Inside the sills, not looking good either.  The arc welded patches were falling apart with rot.  :-(





Anyhow, that's enough of the negative stuff.  I have thousands more boring photos of the nasties that I found.  Hardtop rust, bonnet beyond repair, 'B' post issues, floors rotten, boot corners, rear valance and so on.  On the positives, the chassis was in very good condition, the hardtop repairable and the rear healboard/radius arm panel good and strong.  Here are a couple more phots of some repairs progress made all those years ago...



and repairs painted....



More uploads to follow.

Thanks,
Chris

[krissto]

I need to quickly add that the door gap was braced while I replaced the floor edge, middle diaphragm and outer sills. Only removed when complete.

[krissto]

By the time we got to 1988/89, the majority of the body tub repairs were done.  To recap:  New middle and outer sills, A posts, B posts, rear wings, rear valance, boot floor sections, windscreen frame repairs and so on.  I also cut the radius arm brackets out of a Spitfire tub (at SpitBitz?) and welded  them into the inner locations normally found on a Rotoflex GT6.  Yep, it was always the intention to move onto a lower wishbone style rear suspension.  We jump ahead with the photo below, but it shows the tub now has at least the outer panels fitted...



You will see a rather untidy looking 4AGE in place in the above. and a painted chassis.  Ignore all that, as it is out of sequence.

Time to go back a step.  On the subject of rotoflex, I bought a used set of GT6 Mk2 lower wishbones, vertical links, driveshafts and radius arms etc., for a cheap price.  Most of it was seized solid and no way could I get it all apart.  Here is where a really good friend (who I unfortunately have lost contact with) came to the rescue.  Being an apprentice mechanical engineer at British Airways meant that he could apply the tools and methods to dismantle and machine back to a usable condition.  All blast cleaned and where necessary, shims and washers to regain tolerances.  I then hand painted most of it in Finnigans primer and Hammerite, so that it looked like this...






This was my 'revision 1' of the rotoflex setup - much has changed since those days of when I did not know any better!  Next step was to liberate the tub from the chassis and sort out the running gear.  To be continued  in the next episode...

[hairdoo]

This has the makings of a rather excellent thread. Please continue.

[jimi]

I just about to ask "is that a?" when I read this

You will see a rather untidy looking 4AGE in place in the above. and a painted chassis. Ignore all that, as it is out of sequence.

[hairdoo]

No doubt the resident scottish Toyota 4age guru homed in on this one

[jimi]

Mar 15, 2021 23:21:31 GMT hairdoo said:

No doubt the resident scottish Toyota 4age guru homed in on this one

hardly an expert, I know a little bit about AW11's but thanks for the compliment

[biturbo228]

Interested to see what you get up to with the rear suspension. I've done some rather radical bits and pieces to mine (as yet untested) and made some little models to work out stuff like camber curves and roll centre heights if you're interested.

[krissto]

So we are now in the year of 1989 and the body weld-a-thon is complete and time to consider what I really want of this car. I mulled over the idea of a 120BHP Spitfire Mk3 engine rebuild but it looked like being very costly and would be a tricky car to drive on the roads (high idle, very cammy, massive webers etc.). Also, that cast iron Triumph engine and gearbox combination is surprisingly heavy for such a small engine/drivetrain combo. It was my younger brother who mooted the idea of a Corolla GT (AE86) RWD engine and transmission. As luck would have it, a neighbour just a few yards around the corner had recently bought an AE86, so I went round and he kindly let take some measurements in the engine bay. There was no looking back now - I was convinced. 122BHP, fuel injection, 6 gears, mostly alloy, etc. At that time, it was fairly easy and not too expensive to buy a used japanese import engine and 'box, so I bought one. That is: a blue top 4AGE (big port) along with the T50 transmission. It came complete with a cropped loom and ECU, which was fine for use as a reference but was intended for closed loop lambda /catalyst. With the chassis now in the family garage and the tub wrapped up and put aside, the work could start on that adaption. The engine and transmission were placed on the chassis and moved around over and over until I was happy with all the angles and so on. The phliosophy was to make as few mods as possible to the chassis frame, suspension towers and bulkhead. This involved the following (not a complete list):



- The front double-pulley/harmonic balancer was machined/parted off to remove the A/C drive. This enabled the pulley to sit behind the steering rack, not above it and no need to relocate the rack.

- The bellhousing was removed and the mount for the clutch slave cylinder rotated and repositioned so that no chassis rail mods were needed. The clutch arm on an AE86 is low down on the bellhousing and would have required a major chassis notch.

- The original cast iron engine mount bracketry could not be used. Instead, lots of cardboard CAD took place to design new engine block brackets and chassis angle brackets such that the original Toyota rubber mounts and plates could be retained.

- An AE86 has the sump bowl at the front of the engine. This is no good for a Spitfire because there is a chassis crossmember between the suspension towers. So I cut the sump pan and moved it backwards, along with a channel for the oil pickup pipe to run along. The oil pickup and filter were carefully extended to fall into the centre of the bowl. No mods were needed to the baffle plate.

- The AE86 4AGE alternator runs low down on the offside, so would foul the suspension towers. I bought a Carina lower mount (same 4A block) and relocated the alternator to the nearside, higher up.

- A small amount of material was removed, in places, from the inner chassis rails and seam welded where necessary in order for the bellhousing, transmission braces etc., to clear. This is perfectly legal and was carried out by Triumph themselves (for the 1500 Spitfire) in places.

A local company made thick steel brackets to my drawings, some of which are in these photos...








Here is the engine sitting in a messy/busy garage on the chassis:





You can just  make out the engine bracket sitting on the stock AE86 rubber mounts and the 45 degree angle section that would be welded to the chassis.

In this next shot, it can be seen again, slightly obscured by the dangling fuel filter.... 





Note also the rotoflex lower wishbone chassis bracket at the rear.  This has the 44mm alternative location point as per TSSC articles by Eikhoff .  The brackets differ from the multi-hole items offered nowadays in that there is a closed section both above and underneath, thus adding strength is using the lower mounting hole.   Before I sign off this instalment, here are some shots of the sump mods - not an easy task and took me ages...
















Thanks,
Chris

[Deleted]

Loving this one! I bought a 4AGE and 'box to fit in a Toledo but my finances had a hiccup and I had to sell the engine. I imagine they're rather costly now?