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I thought it might be good to start a thread on the rebuild of the Mk1 Spitfire as a road car. So here is the start.

This all started back at the end of 1999. A friend had a complete but extremely tatty red-ish Mk1 Spitfire that he had been storing in a barn for many years with the intent of restoring. Due to too many other projects and a lack of space he never managed to get round to it and the farmer who owned the barn was looking to get the use of his barn back.

At the time I was competing in sprints and hillclimbs in my Mk2 Spitfire but as this was also our sole daily driver at the time this was becoming increasingly unwise! So I agreed to buy the car with the intention of building it up as a dedicated competition car and for the princely sum of £200 it was mine on the 1st December 1999. The car was right hand drive, UK spec car but had been bought as an unregistered import somehow of unknown origin. The previous owner did have full supporting documentation from BMH which showed that the car had been sold by Triumph to a dealer in London in 1962 after which it's history disappears until my friend acquired it in the late 1980s after which it sat in the barn until bought by me.

The bodywork on the car was very poor and after starting off white had obviously been resprayed at least 3 times in different colours. There were vast quantities of filler all over it, the bonnet in particular looking (and weighing) like it had been skimmed with at least 1/4" of whats seemed like a kind of cement filler all over! However the chassis was in remarkably good condition and everything was there except for the soft trim.

Six years and two children later the car was finally MOT'd (bit of an epic until I found the right MOT station and tester) and registered (Glasgow DLVC Office absolutely fantastic - but now closed) in October 2005.

Back to the start though. I have no photos of the car from then unfortunately. This was before the days of mobile phone cameras, or in our case a mobile phone and I was never any good at remembering to take the camera.

First job was to separate the body and the chassis and to keep everything straight I built a wooden box frame (a bit like a Marcos wooden chassis) with casters to take the body while working on the chassis.

New outriggers, a new front crossmember and a trip to the local shotblasters tied onto the roof of my new company lease Rover 200. No roof rack but a thick blanket on the roof and ratchet lashings through the door opening did the trick.

Chassis primed and painted Triumph white all the mechanical bits were sorted while I sent the body away on it's wooden horse to be rebuilt.

This is it all built up and ready for the body. Part 2 to follow.

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:smile:

I’ve got a very similar pic of my Herald resto in progress..... it’s pretty much the only pic.....

Look forward to the next instalment 

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Thanks Nick. Yes in the days of the 'Box Brownie' I never had the camera with me.

So while I'm letting my porridge go down before going on the turbo trainer for the day's exercise I thought I would get on with part deux.

I had been competing in my 1965 Mk2 which was also my 'good' car. This was (is) a bit special as it ran a 2.5L six with rotoflex rear and a close ratio TR6 J Type OD gearbox. It also has a full glassfibre bodyshell. Bonnet, doors, bootlid and tub. Basically everything bar the chassis that I had built myself in 1986/7 long before the T6 Fabrications one came along. Weighing almost the same as a standard steel Mk2 it was quite quick and reasonably competitive but without destroying it as a road car it was never going to get much better.

This is the car in 1989 shortly after the wife and I returned from our honeymoon!

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The new car was going to be built as a dedicated hillclimb/sprint car to compete mainly in the Scottish and North England historic event and championships which were very active at the time. For the historic classes rules were essentially MSA road legal requirements and fairly relaxed but it was going to be a four cylinder with swing axles, full cage for safety and to stiffen the car, have a steel 'core' but be absolutely as light as possible everywhere else. It was also going to be Royal Blue.

The details of the car obviously evolved over the years as I competed but the original mechanical spec was as follows (I have it all written down!)

Engine

Mk3 1296cc small bearing. Block bored plus .020" (1315cc actual). Crankshaft tufftrided and balanced. Conrods polished and balanced. New big end bolts and small end bushes. Pistons, standard type plus .020”, balanced. New camshaft bearings.

Ported cylinder head (stage 3), modified valves; inlet 1.44”, exhaust 1.32”. Hardened exhaust inserts. Bronze guides. External oil feed from main gallery with a 2mm restrictor and feed in block and head blocked off.

Kent Cams TH6 race camshaft 290O duration (42-68 78-32), 0.302" lift. Lightened followers. 1.6:1 ratio roller rocker gear with solid spacers. Single row timing chain.

Spitfire 1500cc high capacity oil pump. Baffled sump - this took a couple of goes to get right as I found the big issue was actually on hard braking rather than cornering. 35psi oil pressure warning switch. Own design of lightweight alloy flywheel, crankshaft pulley and engine backplate. Rocker cover and crankcase vented to oil catch tank. 13 row oil cooler and thermostatic adapter (Mar 04).

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OOps. Managed to post before I finished....oh well part 2 1/2

Cooling pretty standard but with an aluminium water pump housing and pulley. I also used the Spitifre Mk1 type of water return pipe as this doesn't have the heater bypass connection (not required for the Webers) and is neater and lighter. I replaced the heavy card radiator side ducts with lightweight alloy ones and because these are also stronger than the cardboard ones they were used to support the radiator instead of the two brackets that bolt to the suspension towers saving a bit more weight (are you getting the point about weight yet :biggrin:). I also fitted a lower alloy panel between the bottom of the front crossmember and the underside of the oil cooler which is below the radiator.

Twin Weber 40 DCOE 18T (ex Lotus Elan) with an electric pump in the boot. Jets, etc took a long time to get fully sorted for tractability and if anyone is interested I can post the whole history but regards power the setup was pretty good from the start - rolling road giving 126 bhp at 7000rpm.

I modified the petrol tank to reduce the capacity and weight but keep it looking standard at a glance. It also meant I could bolt in an 4mm alloy firewall using the same mounting bolts as the tank which met the MSA regs whilst also doubled up to stiffen the bodyshell. One component, two jobs - weight again.

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For the distributor I wanted to keep the cable drive for the tacho but not use the dreadful Delco unit. So I used the body from a Lucas 22D6 Vitesse unit with the upper internals for a four cylinder D4 and a modified advance curve. I cut off the vacuum unit but kept the vernier adjuster and fitted an Aldon ignition unit and Lucas gold coil. Originally there was no rev limiter but I soon fitted an Omex unit set to a hard cut at 7300 rpm as the engine just wanted to rev until it blew.

Exhaust is a Bell 4-2-1 unit with a single pipe and silencer. It looks like the standard Mk3 system without the centre resonator but Bell did a special for me in 1 3/4" diameter instead of the standard 1 1/2".

Gearbox was a close ratio 4 speed with one of the original John Kipping uprated mainshafts with an alloy bellhousing. I started off with a standard 6 1/2" clutch but this was too puny so rather than fit the larger later (heavier) clutch I soon went for a 6 1/2" paddle job which was excellent and could cope with full power standing starts.

After a lot of debate with myself I settled on a 4.55:1 final drive built up on my old Quaife unit. With the close ratio gearbox this was great for standing starts and short twisty/steep hills but with a top speed of 102mph at the 7300rpm rev limit not so good for big tracks. However as I didn't do too many of them it was a good compromise and driving the car on the road to/from events was electrifying :biggrin:.

Part 3 suspension next up.

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Great stuff, very interested in this - gives me things to daydream about doing to my Spitfire!

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Today's episode of the original build history from early 2000s is on the suspension and brakes.

At the front I used GT6 uprights and steel hubs. I have always used the standard studs and plain wheelnuts without any issues although I did replace them all and am scrupulous about torque on these. Yellow Polybushes, AVO height adjustable dampers and 480lb springs. The standard 5/8", anti-roll bar with the yellow polyurethane bushes and standard drop links.

Spitfire steering rack,which was shimmed 5mm to remove bump steer and a nice Astrali eleven inch diameter steering wheel that came with the car and just needed a bit of a polish.

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At the back I started off with what was essentially a Spitfire 1500 setup of swing spring and long halfshafts. However when I tried to fit the body it wouldn't fit over the wheels so I had to go back to the shorter axles!! With the lower weight and reduced ride height I wasn't sure that just using a lowering block would to be enough so I also shortened the rear uprights uprights and fitted an adjustable rod end spring attachment. It turned out that this was the case so good guess. I fitted the rod-ends on the uprights with rubber bushes filled with grease to prolong their life. I didn't bother with this on the ARB drop links on this car although I probably will before it goes back on the road.

This pic shows the later rear dampers but otherwise largely as originally built

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Radius arms were adjustable with yellow polybushes. These just make adjusting the rear tracking so much simpler than the shims and you can get the exact setting you want rather than the nearest shim. I have experimented with rear to-in on these cars and even small differences have a big effect on the feel and behaviour of the car so it's worth the effort here. Dampers were GAZ adjustable standard length ones.

I set this all up using a ghetto alignment system with basic stuff. Tape measure, bits of thread stretched between oil cans, plumb bob and a home made camber gauge and caster gauge. Just as good if not better than Mr Kwikfit it just takes a bit longer. Because the car is relatively light I could set the corner weights using bathroom scales and a bit of ingenuity.

I have played around with the camber and toe over the years but final settings at the front were zero toe-in, 2O negative camber, 4.5" ride height at the front and 1/16" toe-in and 4.5" ride height at the back (4" where the chassis goes under the rear axle).

The car runs on 5.5" x 13 Triumph pattern steel wheels, because they are very strong, because unless you are prepared to sell a kidney they are no heavier than most of the alloys out there and because I have a few sets. And because painted silver I think they suit car without the later centres fitted.

Tyres are 185/60 which are the largest I can fit without modification and keep within the rules. These started off as 1Yokohama 032s, then 048s soft compound and finally a set of super soft Avon ZZR A24 compound for shorter courses or long tracks in cool/wet weather (they overheat on long track/hot days). Even these could do with being a bit stickier for very short courses but slicks are not allowed and the other racing options are crossply tyres which are a no-no for the swing axles due to the camber change.

The suspension was subject to a lot of testing and tweaking over the years as you can imagine.

Roll control is critical for the Spitfire to minimise camber change and the consequent roll induced lift, reduction of tyre contact, rear track reduction and toe changes. Keeping the car low and using a stiff swing spring at the back - to limit ride height change - is a start but you mustn't make the back end too stiff in roll. The other issue is traction particularly for sprints and hillclimbs where the the tracks have lots of camber change on the bends just where you want the back end to stick and get the power down. So the front needs to do all the work here. Escorts and Midgets etc have a similar issue which is why you see those pictures of them cornering hard with the inside wheel off the deck. However they can get away with very soft rear springs to allow roll because the live axle keeps the wheels perpendicular. The Spitfire needs a stiffer rear end to keep camber changes under control on bump so your options are a bit more limited.

I quickly replaced the anti-roll bar drop links with solid adjustable ones. This had the added benefit of allowing the bar to be fitted with zero load as they are all twisted. I found that the difference couple be 1/2"-3/4" in the length of drop link side to side. Centre bushes were also changed to the hardest red polybush ones and this made a noticeable difference to the initial turn-in of the car which was much more crisp. I experimented with a bigger ARB from the Mk4/1500 but didn't like it, the initial turn in wasn't any better and it just promoted through the corner understeer.

The car is very sensitive to tyre pressures particularly at the back because of the camber change. Triumph specified a rear to front bias to encourage understeer but for performance the bias is front to rear and a bit lower overall due to the wider tyres. 21 front and 14 rear on the 185/60s against the 21 front and 26 rear for the standard car on 145/85 radials.

The suspension mods front and back got quite a bit more radical after this but I'll cover those later on.

In the meantime brakes.

At the front I decided not to use the bigger GT6 brakes as I didn't think they would be needed for sprints and hillclimbs and would just take too long to warm up. I had acquired a pair of standard 9" discs that had been drilled at Stafford and have used these ever since without issue even doing the occasional long circuit sprint where you're breaking from 100 plus into a first/second gear hairpin. My car had the old style uprights with the separate caliper mounting bracket so I used the brackets and fitted a pair of reconditioned Type14 calipers because it's easier to get the pads.

Pads were initially Green Stuff but I never really took to them as they were only ever 'barely adequate' even on the road. Cold performance wasn't great until they warmed up but this seemed very difficult to do. So after nearly coming a cropper on a hot entry into the downhill right-hander at Harewood I ditched them for a set of Ferodo DS2500. These require bedding in thoroughly before use, which was done on a local trading estate one quiet Sunday morning. Very smelly process but you can tell when the pads are ready! I have been extremely pleased with them ever since. They work very well from cold and just get better but in a very consistent way.

The back is standard 7" drums and shoes - basically because that's all you can get. Drums started off as standard but I changed these to the Alfin alloy type fairly early on - painted black to help get rid of heat. I played around with different slave cylinder sizes but after trying every size at least twice finally settled on the biggest 0.75" cylinders from the Mk1. I like the balance they give and with the Alfin type drums I've not had issues with them getting too hot.

Master cylinder is standard single 5/8" bore. I have debated for years about whether or not to fit twin master cylinders (usually while changing the rear cylinders for the umpteenth time) but have always decided against it. Brake pipes are copper with brass fitting and stainless braided hoses. I use DOT5 brake fluid. I know the debate over both of these but I have used both for almost 40 years without any real issues. The green Spitfire has done almost 200,000 miles since I rebuilt it in the mid 1980s including competition use. I think the key is to have it all properly secured. Same with the DOT5 really. It has a couple of main issues, lubricity and foaming but as none of my cars have ABS this isn't a problem.

Handbrake is the lovely fly-off type. These are such a joy.

Next episode will cover the body, cage and lightweight panels

 

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I can tell you enjoy the suspension part of it :smile:.  Which is good 'cause you need to experiment constantly to get the best.  Like you adjustable rear vertical links.  Simple.  Elegant.  Effective.

Agree with you on Green Stuff and the DS2500s.  Ran DS2500s on the Vitesse from 2009 until last year.  I think we finished the bedding in/curing at the Nordschleife on the 10CR 2009 - they were certainly very smelly/smokey afterwards! First set lasted really well until finished off by a track day.  Second set lasted less well.  A dry track day with both lead-footed sons cooked them pretty well (and the caliper seals), hence now vented. Have reverted to M1144s since I went vented as they have a bit more bite, especially when cold.

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Oh yes. And thank you. I like to keep things simple wherever possible. Suspension allows almost endless pottering potential :biggrin:

I can imagine a day at Nurburing would see off the brakes. The Vitesse can be pushed remarkably far and is no lightweight. M1144s seem a good compromise for a road car though.

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Wasn’t a day..... was one lap.  A pretty hot lap it’s true..... :roadrage:

A Castle Coombe trackday was more damaging. That was the dry one. Previous wet ones were just about ok. It weighs about 970 Kgs empty.

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4 hours ago, Escadrille Ecosse said:

Drive it like you stole it

The boys were..... especially the younger one.  Just like Playstation apparently.  Other than the absence of a reset button obviously.........  Still, at least his gaming experience meant he got back on the throttle and drifted all the way around Quarry rather than just plowing off into the tyre wall. He (and I) now know that while it is possible to arrive at Avon Rise at 105 and get round, it does make things a bit tense thereafter as there's not alot of braking room left before the big one......

Anyway, time to stop spamming your thread!

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May the fourth be with you. The body and other stuff.

The Mk2 was completely fibreglass but the plan with this car was to keep the main core steel, to comply with the spirit of the competition and because I wanted to keep the basic originality of the car.

It also needed to have much better protection in the event of a crash (I was now married with two kids) whilst also being as light and stiff as possible. Spitfires with their separate chassis are not really either. Drive one along even a normal A or B road and put your finger on the gap at the B post and you’ll know and getting the weight down was not going to be made any easier with the addition of a full roll cage.

Because I was struggling for time and wanting to get the car finished the thoroughly frilly body tub was sent off to Chic Doig for a rebuild while I got on with the chassis and mechanicals. The brief for Chic was to rebuild the shell but leave off the outer rear wings, boot floor and rear valance which I initially intended to replace with GRP to save weight. I then had the completed shell shot blasted and phosphate primed.

To make life easier and to keep the shell square while working on it I had also made a wooden box frame out of plywood and the shell was screwed down to this through the body mounts until it was finally ready to fit to the chassis. I also removed all any brackets that were not essential to save weight, spare wheel mount, hood frame brackets (car was hardtop only), etc.

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I wasn’t happy with any of the commercially available roll bars or cages because they are too compromised by being made to fit around the hood and trim of the Mk4/1500. So I built my own.

The main hoop was made to fit right out to the B posts, the rear braces going back to pick up on the chassis mounts on the rear spring tunnel. These would also be fitted with mounting points for the harnesses. At the front I had wanted to fix to the outriggers but that wouldn’t work unless I removed my right leg. So they had to bolt in at the bottom of the A post. But there was a cross tube behind the dash and door bars and brackets to support the top of the windscreen frame. I needed the door bars because the doors would be GRP but mainly because they would make a torsion box to stiffen up the shell across the door opening. The bars form a V on each side triangulating the front onto the much stiffer rear of the tub. The full cage added about 35 kg to the car.

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After more thought I decided to abandon the plan for GRP panels on the tub mainly because the considerable loss of stiffness wasn’t worth the saving in weight. So after welding these in I primed and painted the underside and inside of the tub before fitting it to the chassis.

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Next up was the GRP. I had (and still have) moulds for everything apart from the bonnet from making the Mk2 and these were used to make a set of super-lightweight panels. All very flexy but not really an issue for a competition car.

You can see the doors and bootlid in the pictures of the chassis and tub. To keep these as light and strong as possible I used just two layers of woven roving cloth rather than chopped strand mat without gelcoat or colour. The bootlid did away with the frame and inner reinforcing panel and I replaced the handle with a Dzus fastener. A friend of mine referred to them being made out of poppadums.

The doors are fully GRP with the standard locks and hinges and fixed Perspex door glass. I kept the door cards to finish things off and avoid finger traps although I did have to turn the inner handles upside down to clear the door bar.

I got rid of the tray moulding on the tunnel cover. It has no purpose on the Spitfire and just makes extracting the cover from under the dash more difficult.

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Weight of the various bits and pieces

Bootlid – 2.1 kg including hinges and ‘lock’. Standard bootlid 7.5 kg

Doors – 6 kg each complete with Perspex windows, hinges, locks, door cards. Never weighed them but the standard doors with glass, etc are in the region of 30 kg each.

Hardtop – 8 kg

When I built the car decent GRP bonnets for the Mk1 were available (pre Honeybourne fire) so I got one from them to a slightly lighter build rather than make one. The bonnet irons were ditched and I made my own aluminium hinges bolting directly to the front grille panel. This also got rid of the chassis hinge brackets and overriders. The bonnet catches were replaced by Dzus fasteners. If they were good enough to fit the engine cowlings on the original Spitfires they should be good enough for this. I saved a little more weight by getting rid of the separate sidelights. All up weight for this was 15kg vs 35 – 38 kg for the steel bonnet.

I also made a front valance with a small integral air dam. This bolted directly to the bonnet which saved another wee bit of weight as it meant I didn’t need the outer parts of the front crossmember.

The protruding stud on the right (car left) of the grille panel is for fitting the timing strut for sprints and hillclimbs.

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Seats are a pair of Corbeau Alpines which were bolted in on fixed brackets and the only other trim apart from the door cars was a pair of rubber mats for the footwells which I took out for racing.

I weighed the car at the council weighbridge shortly after it was finished and with a full tank, spare wheel, tools, fire extinguisher and myself it weighed 675 kg, so pretty much 600 kg track ready compared to about 730kg for a standard Mk1.

Finished, MOT'd and registered with an un-issued age related Glasgow plate.

Next installment is on improvements to the engine and experiments with the suspension.

 

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Not got round to the promised write up yet as I have been busy on the next stage of the actual rebuild which is to replace the super lightweight bootlid and door skins as they are too floppy and fragile for everyday use.

I'm starting on the bootlid which I am going to make using carbon fibre resin infusion rather than GRP. I wanted to try carbon fibre for the car when I first built it but to do the job properly you really need to cure it under vacuum to get maximum benefit. Simple hand lay up gives a much higher resin content and you might as well use GRP and safe a wodge of cash. Nowadays though vacuum bagging equipment is much easier and cheaper to get so I am going to give it a shot. Once I've mastered this on the smaller panels the plan is to make a complete bonnet.

Resin infusion is the most efficient DIY way of making carbon fibre parts. Basically the dry carbon cloth is laid in a mould. This is then covered with a plastic bag and a vacuum is applied to draw out the air and whilst still under vacuum epoxy resin is introduced into the mould and the whole lot allowed to cure. With this you can achieve an almost 1:1 ratio of resin to reinforcement compared to maybe 2 or 3:1 for an open hand layup resulting in a much lighter and stronger part.

I have an old mould I made years ago but unfortunately this won't do for the resin infusion process as there isn't enough flange around the mould to seal the vacuum bag and various other bits and pieces.

So first step was to dig out the old mould, clean it up and use it to make a new lid that will be used to make the pattern for the new mould. Got a bit bashed unfortunately so had some repairs to do first.

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Layup complete.

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Out of the mould and ready to be trimmed and then polished within an inch of its life

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Fitting correx board flanges to the part using hot glue. My glue gun is really too small for the job but did until the bigger one arrives

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Chemical release and wax applied ready for gel coat

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Contrasting grey gelcoat

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Layup complete. Gelcoat, surface tissue, four layers of chopped stand mat and a layer of coremat for bulk. Now needs to cure for a few days.

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I am really enjoying this thread.

Always a sucker for a Royal Blue car.

Looking forward to the next instalment of the build story.

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Thanks Tim.

Appreciate the feedback, glad you are finding it interesting.

As for the blue, I think it really suits the car too and isn't that common either. 

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Fantastic effort.

 

Me, I'm also a Royal blue fan
with the T r i u m p h lettering it is just so classically the sixties icon :cool:

 

Ian.

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On 5/21/2020 at 8:36 PM, Escadrille Ecosse said:

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That looks so cool! I love it. 

Really interesting build, I keep re-reading. 

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Yes Tim.

Basically I added a vertical air dam to the bottom of the standard front valance and then took a mould and made it all in one piece GRP.

Idea was to make it as unobtrusive as possible but still restrict a bit of the air from going under the car and push it round the side. I had originally planned to paint the bottom bit black but once I had done the Royal Blue decided it wasn't that obvious. It was also a bit deeper at first but when I got a trailer it caught on the ramps so I had to cut a bit off.

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Yes, less a spoiler, more an airdam.

I fitted a combination of the two to my Old Blue Vitesse, and I think the design will work on a Spitfire/GT6

 

SPOILER.GIF

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Back out to the garage this afternoon working on the bootlid moulds but in the meantime more on the engine and suspension.

Once I got the car on the road and started getting to grips with the car on the track there then began a process of regular winter modifications intended to improve the car, some of which were successful and others not so!

On the engine front I the biggest issue was the mid-range performance. Even with the close ratio gearbox and short diff it was difficult on very short, twisty hillclimbs to keep the engine in the very high and narrow rev band where the Kent race cam worked very well. The top end was very good and a lot of experimenting with jetting of the Webers did help fill in the hole to some extent but I was never very happy with it overall and eventually after three seasons came to the conclusion that I was only going to resolve the issue with a change of cam.

Where to go though? After much debate, investigation, swithering, etc I finally settled on a Newman race cam with some trepidation as the 300 degree duration was slightly larger than the 290 of the Kent. Rightly or wrongly this ultimately came down to my view that the Kent profiles are largely based (or so I have been led to believe) on crossflow Ford development whereas historically (factory, Kastner, etc) Triumph profiles are all symmetrical. In this case 42-68 78-32 for the Kent and 40-80 80-40 for the Newman. I am very interested in opinions on this one though.

Anyway. Cam and followers purchased, the head was removed for the change and then of course all the other required mods - and procurement 'opportunities' - come to light. Funny how this is never straightforward or cheap. The Newman cam has a slightly greater lift than the Kent, 0.315" vs 0.302" and this required the head to be sent off for the guides to be shortened slightly and the head skimmed a bit to get the compression ratio up to 11:1.

I also had to replace the 1:1.6 ratio roller rockers with new ones at the standard 1:1.5 ratio to get the geometry back to somewhere sensible. Although I did manage to recoup some of the cost selling the old ones on ebay. And the standard pushrods had to be replaced with shorter tubular ones to cope with the extra cam lift and reduction in head thickness. There was actually just about enough travel left in the adjusters to take the pushrod but there was so much sticking up above the rockers that they hit the inside of the rocker cover!!!!

Have gone this far I also ended up fitting a duplex timing gear and chain - what the heck eh!

All this required yet more work on the Weber jetting but more importantly it made a significant improvement to the behaviour of the engine. With the Kent nothing at all really  happened until about 4000 rpm when the torque came in with a bang and kept on going. The Newman feels very different, the torque comes in much more progressively and from about 3200 rpm which makes it much more effective for hillclimbs, etc. On the road too the Newman cam is much easier to drive around without the sudden cliff the Kent had. Subjectively driving in traffic it feels much like the family base 1.2L Fiesta when it's loaded up with four people although the paddle clutch requires a bit more sensitivity!

Suspension wise there was a lot of experimentation but I've run out of time to go into this at the moment but here is a wee taster.

20200528_120106.thumb.jpg.2e089f38bf493371a74e836fedfa9dc5.jpg

 

 

 

 

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Hey Steve!  He's got a GRP spring!

RE the cam..... slightly confused about which Newman one you have as the numbers don't match what they publish now, maybe because they changed - seems to be somewhere between the PH3 and PH5?  But yes, I think your comments re the Kent cams and their Ford provenance are correct.  Others have commented on their narrow power band.

I have half a Newman PH3 in the Vitesse (the inlet half) and that has 300º duration and 0.290" lift.  The exhaust half is PH2 (280º/0.270").  On injection (single TB at this point) it gives a slightly loping idle at 800 rpm and it pulls from 1000 rpm. There's no "coming on cam" effect as such with grunt building fairly linearly from 2000 upwards with it really getting going properly from just under 3000 rpm and dies off a bit just over 5,500, though I don't think the cam is the limiting factory there.  No doubt the electronics (3D ignition especially) helps get the best at the bottom end but it works very well.  This with standard (and somewhat shagged now) rockers, pushrods etc.  Cr 10:25:1 ish.

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