Living with the Mid Engined Spitfire
Unlike a standard car many of the parts on my Spitfire are custom made or stolen from another car manufacturer, so inevitably things need fixing, changing or tweaking. I guess my little car will never truly be finished.
I have had to run a vacuum tube from the engine to the clutch servo, all 3m of it. The Range Rover vacuum pump over heated and seized, catching fire! not a good thing when it is positioned under the fuel cell. I have yet to drive the car with the conventional vacuum attached, but it feels quite nice at idle.
New Face 🙂
Yes, at last i ditched the old battered Vauxhall Astra bumper for a new one, and one with no cracks or bangs. Fitting was quite straight forward, 20cm out of the centre, and 15cm from each end. I reinforced the new bumper with aluminium and steel, ensuring the joins were well bonded.
Then I made a splitter, I made a wooden buck and used that to make a carbo fibre outer casing. I made of a vacuum bag and cured the splitter in the vacuum bag.. unfortunately the bag snagged the carbon fibre ruining the look. I then filled the carbon casing with glass fibre,, Painted the whole thing black, the wrapped it in carbon vinyl.. I think it looks really cool.
As a result I bought a 1″ (25mm) master cylinder from Murray Motorsport. This gave me the required 1″ free travel on the clutch, but… I needed body builder legs to operate it! I mean the clutch was seriously hard to press, which made driving the car really hard.
So I have now fitted a remote servo to the clutch master cylinder, and , as my engine is at the back of the car and it’s turbocharged, i had to fit an electric vacuum pump. I used a supercharged Range Rover unit, small and quite cheap. This totally transformed the clutch, its still hard, but very positive. The CG stage 2 clutch is quite binary, quite hard to pull away slowly, its either on or off. But it is still being run in.
MISFIRE – Boost control
I am still have an issue that the boost is capped at 15psi, it seems that the engine keeps going into limp mode. I know the N75 valve is working perfectly, there are no error codes, so, it must be the ignition. So I have ordered a brand new set of NGK coil packs and BKR7E plugs.
26th August 2022
A lot has happened over the past month, I have now fitted a new CG Motorsport Stage 2 clutch and an exhaust cutout.. The Clutch means I can use all the car’s power and the cutout means it sounds better…
27th July 2022
For some time I have had a cold start issue; the engine starts perfectly, but revs at 1200 rpm, exhaust header/manifold glows red and the engine sounds “different”. Originally I thought this was a lean issue, i.e. too much air being sucked in, but when we checked the engine timing at cold start it was running at 6 degrees after top dead centre ATDC (you would expect it to be running at x degrees before top dead centre BTDC.
When the engine is stopped and restarted, the engine returns to normal and runs perfectly.
There are 2 possibilities causing this, VVT (variable valve timing) or a bad ECU. The VVT was changed a few months back, so the only other possibility now is the ECU. So, I have ordered a new Audi TT ECU, 8N0906018H. I did buy a VW Passat ECU, but this did not work and had to go back.
You can’t just plug an ECU in and expect it to work! It is not just the map that is different, but also all Audi ECUs have an immobiliser fitted, this means that unless you have the original key, ignition lock and ecu the car will not start..
To turn the immobiliser off you have to put the ECU into boot mode, (power it up whilst shorting a pin to earth) then run some software which extracts the 512k ROM, edit that ROM file and then upload it back to the ecu.. Then you have to flash the ECU with a MAP that is specific to the engine’s build, i.e. injector size, turbo and so on.
14th July 2022 – New Pulsar Turbo
The past month has been a bit chaotic, the poor little car has been in bits so many times!
After fitting the new GT28 71RS turbo, we noticed black smoke coming out of the exhaust; so I guessed the new turbo had died. I ordered a new Pulsar G25 550 turbo, and fitted that. The Pulsar needed the downpipe to be extended by exactly 2″ over the GT28.
Fired the engine up, and immediately noticed the engine was still smoking, So I bought and fitted an AFR gauge so i could better check how much fuel was being used. I had noticed that fuel economy was pretty bad, using gallons of fuel over short runs. The new AFR gauge confimed the engine was running REALLY REALLY rich. however the ME7.5 ecu was reporting a perfect mixture. So I bought a new wideband O2 sensor. this still made no difference.
I asked my son to unplug the WBO2 sensor and he noticed that there was a broken wire in the socket, on further examination we saw that both sensor wires were broken.
So I made a new WBO2 sensor socket with a longer loom, and wired it up. Boom.. the AFR is now spot on.
With the G25 turbo the engine makes between 450 and 480 bhp, what does that feel like in such a light car?? scarey! It is very very fast, and shoots flames..
1st June 2022
I was so pleased with my new exhaust, seemed like all I had to do now, was drive the car… So on Friday I started it and drove 700 yards to the local shops, when I looked in the rear view mirror, there was a puff of white smoke coming out of the rear as I drove home. When I got back to my garage, I looked at the exhausts, and all of a sudden they both started belching white smoke, I mean enough to fill the drive, garage and the neighbour’s drive!
The turbo had blown.
Yet another issue to deal with.
So I ordered another cheap Chinese turbo, that arrived yesterday, fitted yesterday evening, and the car is back up and running again 🙂
Davies Craig has at last replaced my faulty EWP80, so I thought I might as well fit taht anyway. This time I made a clamp to mount the water pump securely, I then discovered I had the coolant flowing the wrong way round the car, so i had to re-route the coolant so the hot (out of engine) ran to the top of the radiator and the cooled coolant from the bottom, via the EWP80 back to the rear of the car.
24th May 2022
A lot has happend with my little car, I have a new homemade exhaust (checkout the link below) and the issue with the car has been fixed.. The car would keep bogging down on acceleration, it turned out that the ME7.5 ECU thought the clutch was pressed, despite all efforts being made to delete the clutch, something in the ECU was not happy.
In the end, I had to pull all the wiring out and “find” the connectors on the ecu for the clutch switch, then it was just a case of joining the 2 wires together.. and voila, iossue gone.. At some point I will fit a clutch switch, so I can have launch control. i.e. hold your foor on teh clutch and accelerator, the engine will rev to about 4k and then you drop the clutch and launch the car..
5th March 2022
2 weeks after filming Officially Gassed and a short break in Jamaica, the car is back on the road. During filming the front pullet came loose, and sounded like the bottom end of the engine was falling out.
I also wanted to fit the big port manifold and matching long nose Bosch injectors.
So, we now have new steel braided fuel lines, new fuel pressure gauge, big port manifold and brand new Bosch 0280 158 123 injectors.
The car runs well, but still feels like sometimes it gets bogged down when you push the accelerator
15th February 2022
Over the weekend I continued to iron out the gremlins, I fitted an original Audi TT fuel rail and fuel pressure regulator, fpr. I felt like the car was being starved of fuel when you hit the accelerator, so if this fixed any running issues, the issue had to be with my aftermarket fpr. We took it for a drive and it flies, I did a number of pulls, from 1st to 3rd, at about 4k rpm in 3rd the clutch starts spinning, looking at the logs, I am pulling 350 bhp. I tried 3 times, same issue, so need a better clutch! There is so much more to come from this car – these clutches are not cheap, upwards of £500
So on the shopping list now.. better fpr, clutch and I also want a set of long nose 660cc/min injectors, so i can fit my big port manifold.
I also had an issue with the electric windows on the passenger side and the horn would sometimes sound when I turned the steering wheel, all little bugs that have now been sorted!
7th February 2022
As usual with a homemade car there are always going to be issues, and I encountered a real pain of a problem. I drove into Uxbridge with my son, at a set of lights I decided to launch the car off the traffic lights, as I did, the engine failed, and cut out, it started straight away but sounded awful.
So we limped home and I started all the diagnostics again, compression check, OK, visually everything looked great. So I bought a hand vacuum pump to test the induction setup, first job was to adjust the turbo’s wastegate so it started to crack open at 12 psi, it had been previously set to open at 26 psi, in other words it never opened! Next job to adjust the Meth injection switch so that started spraying at 12 psi, it was set at 15 psi before. But the car still drove like a dog.
In the end I loaded the induction system with compressed air, and sure enough a hose coming out of the turbo had split. So I changed the last remaining original hoses for a new setup, I also bought and fitted a rebuilt Forge 007 dump valve.
The car still ran like a dog!
by now I was getting pretty despondent, so back to loading the induction with compressed air, then i found it.. a small silicone bung had blown off the underside of the inlet manifold making a 10mm opening on the underside. So I removed all the bungs, added Gorilla glue and heavy duty zip ties and sealed them all up for good.
Now the car runs like a dream. DOH
12th January 2022
That’s it for now, all the MAJOR upgrades are done.. Yesterday I fitted the external electric water pump. I bought an EWP80 made by the Australian company Davies Craig https://daviescraig.com.au/
These pumps are awesome, I fitted one in the last car I made.
The Spitfire’s original Audi pump is struggling to pump the 6.7 litres of coolant round the car, so a little help will not go amiss. These are straight forward enough to fit, drain the coolant, fit the pump in line with the pipe that goes to the bottom radiator connection.. If like me, you are having it turned on permanently then you have to drill 2 x 3mm (1/8″) holes in the thermostat. Whilst I was at it I also fitted a new thermostat as the old one has never been changed.
Wiring is simple, just 3 wires, 1 goes to the ignition switch, the red goes to permanent 12 volts and the black goes to earth. Then it is just a case of filling the system and bleeding all the air out of it.
9th January 2022
I have now fitted electric windows in my car, they are awesome, click the image here for more information
4th January 2022
Wow, I can’t believe it has been 2 months since my last update. So what has been going on?
The car has been for it’s 2nd annual MOT test, and passed with no issues other than a worn tyre. So I treated it to 4 brand new Michelin Pilot Sport tyres, and these things are really grippy!
I have also re-engineered the way the rear shock absorbers connect to the lower suspension arms. Doing so has raised the rear of the car by nearly 1/2″ or 15mm. This means I now have suspension, and the ride is way more comfortable.
I have also changed the induction system so it sucks cold air through the side vents. Having the intake right behind my head was annoyingly loud, with the sound of air being gulped in.
Another job that needed doing was changing the rear gearbox mount, the engine is held ice and tight now and doesn’t jump all over the place on hard acceleration….
Other goodies bought include a new Davies Craig electric water pump and a kit to convert the wind up manual windows to electric.. But fitting those bits will have to wait until the weather improves.
9th November 2021
I have now fitted the new injectors and added a new map, in theory the car is now nudging 400 bhp, it is really fast but also feels quite planted when driving, the car does not feel twitchy of out of control, it drives so nicely.
On Sunday, i removed the gearbox, its so easy to do, and we checked the LSD, i was expecting to see it had worn away, but no it is still in perfect condition. I also made a pair of bracket to better secure the fuel rail, and a couple of stainless steel straps that wrap around the engine mounts, trying to stop the engine moving so much through acceleration.
25th October 2021
The car is back together now, but further upgraded, I changed the turbo to a GT2860RS turbo, much bigger than the K04-015 I had, this can make way more power, up to 400 bhp. I still need to change the injectors to bigger 630cc ones, but already you can feel the difference in power. The car is seriously fast, but I have to be careful, it is running very lean so I am limiting driving it until its complete (i.e. new injectors).
I have also removed one of the boxes from the exhaust, so it is much louder now. I had to rework the exhaust to suit the turbo, so I have gone V-Band, and split the exhaust into 2 segments, a short downpipe from the turbo and then the silencer.. The car now shoots flames 🙂
22nd September 2021
New rods and pistons sourced, I am going to have to balance them, but they look awesome, second hand, so a quick clean in the dishwasher should do the job
21st September 2021
I have decided to rebuild my engine, the AWT has cast conrods, this limits the maximum boost I can put into the engine, and ultimately the amount of power I can get out of it. I have now pulled the sump of and taken out the pistons and rods. I have a nice set of forged rods ad pistons on their way, Max Speeding rods and BAM pistons, these are much stronger and have a 20mm gudgeon or wrist pin. The original AWT rods have a 19mm pin.
So a new head gasket, timing belt, pulleys, rods, pistons, bearings etc. on order. Also changing the oil pump, as it had to come out to get to the crank.
Should be like a new engine when its finished.
Looking for 400 bhp next, so need to save up for a bigger turbo and the stainless to make a new 3″ exhaust.
15th September 2021
I didn’t see that coming!
I pulled out of my drive and heard this rattle coming from the engine, then it died. I tried to start it but nothing. So I pushed it back into the garage. Timing belt Ok, nothing electrical, a quick compression test showed nothing, zero compression on any cylinder.
I took the head off and saw 12 of my 20 valved were all smashed, and every piston and a small gash from the centre inlet valve. So, all 8 exhaust valves and 4 of the inlet valves were bent.. But the timing belt was perfect, maybe it had slipped, but why?
I pulled the lower cambelt cover off and saw a 1 inch square piece of 1/8 inch plastic wedged between the belt and the pulley.
That’ll be the reason then. So I have now acquired a new head, a big port AGU head, this has inlet ports that are twice the size of my AWT’s head. I’ve stripped it down, and transferred teh VVT (variable valve timing) over to the new head.. But wait..
I have ordered my new parts from AUTODOC, and it will takes weeks for them to come from Germany, So I have decided to rebuild the engine. I have ordered some new BAM pistons and Maxspeeding forged conrods. This will allow me to increase the power of the engine from its current max of 300 bhp so 500 bhp plus..
Just need to wait for all my bits to come..
15th August 2021
This weekend I finished fitting the anti roll bar. I welded 2 bits of 40mm x 40mm x 5mm angle to the existing Audi A4 B7 anti roll bar mounts. The TT roll bar now fits like its was designed to be there.. Wow, what a fit!
The car drives so much better now, the rear feels less bouncy and much more stable, not just in the corners but also on the straights. Obviously I have lost all my rear body roll, so the car feels really planted and squat when cornering. I still get some tyre rub on the wheel arches, but short of fitting longer springs or re-designing the rear arches, there is not much I can do about that.
On a roll, i also fitted a secondary electric coolant pump, again from a scrapped Audi TT. On the TT this little pump stays on after switching the engine off and pumps coolant to cool the turbo, on my car, it pumps coolant round the car’s heater matrix. As the car engine is in the back, the engine’s water pump isn’t quite man enough to pump round the radiator AND the heater.
The pump was broken when I got it, I machined a new pump housing and a friend TIG welded 2 aluminium pipe fittings to it.
11th August 2021
Over the weekend we scrapped a 1999 Audi TT, removing most of the bits that might be useful at a later point. My eldest son, Dominic suggested we try and fit the rear anti roll bar to the back of the Spitfire.. I have tried various ARBs before, but none fit due to the gearbox being in the way.
Yesterday, I gave it a go. The first steps was to mount the ARB drop links, this meant drilling and tapping the lower suspension links. Surprisingly the ARB fitted perfectly, almost made to measure. One last job, I have to extend the chassis anchor points, then we should be good to go. I have ordered some 40x40x5mm angle steel, which will hopefully be here for Saturday.
So its now August 2021.. I’ve done about 500 miles in my little car. So much has changed since I first legally drove it in December 2020.
I now have a limited slip differential, the car makes so much power that the back wheels would spin changing up the gears. Now I have so much traction. Coupled with my new gearbox, the Spitfire will accelerate from 0-60 mph in 3 seconds and just keeps accelerating. I also have Meth/Water injection. This keeps the charged air ice cold and dense as it is ingested by the 20v 1.8t engine. Dense cold air means more power! its not like NOS, but certainly has a drastic effect.
The front and rear shock absorbers have been replaced, I still need to change the springs to make the car less jittery on a rough surface, but man, put your foot down in any gear and this little car is like a rocket. Certainly the fastest car I have ever driven, and I am not sure there is much on the road that would keep up with it..
I have nice Oz racing black alloys, they look really cool, staggered to wide rears to match the 225/50r17 rear tyres.
So I continue to drive my little car, it puts a great big smile on everyone’s face (apart from Spitfire owners 🙂 )
13th May 2021
So much has happened to my little car, not all great 🙁
The Limited Slip Differential has now been fitted, It wasn’t the easiest job, but I got it in, which is all that matters. It has transformed the way the car drives, no more wheel spinning while accelerating up through the gears, it feels properly planted now.
I did buy a Quaiffe LSD, but it didn’t fit! The drive shaft flanges were too “fat” to fit in the differential, In the end I went for a plate LSD, which cost £20 on ebay! it consists of 2 hard steel/iron plates with 4 very powerful springs in between. I had to grind down the edges by 2mm as it was slightly too wide to fit in. But it fitted..
The next BIG job was to sort out the front steering once and for all. I have now made custom hubs, these are basically standard Triumph hubs welded to Audi A4 hubs.. or rather the 5 bolt flange part of the Audi hubs. This has allowed me to use Audi brake discs. To use my BMW calipers I had to make aluminium adapters.. I have also raised the steering 2″, To do this i made a 2″ thick box frame that is welded to the chassis, below the steering rack and suspension turrets. This allowed my to fit shorter springs, lower the car at the front and maintain an OEM steering geometry.
I also have some new wheels on the car, gone are those Fox alloys, I now have MSW by Oz Racing alloys. Staggered, 8.5″x17 on the rear and 7.5″x17 on the front. I went for 225/45r17 rear and 205/40r17 on the front. This means from a tyre size my back ones are correct to keep the speedometer correct.
Driving the car is fun, it is very very fast, I had a new high boost map added, the car produced so much boost it blew the intercooler to bits! unfortunately this also did some body damage 🙁
The one thing we did learn from driving it, especially on long runs, it needed sounds!
So I have now fitted as Pioneer bluetooth head unit and 400w amplifier along with matching Pioneer speakers..
As I said driving the car is a blast, it hits 80 plus mph really quickly, pulling almost .6g acceleration, which as I understand is quite good for a road car.
So What as of the 27th January 2021 needs doing?
New wheels – they are on my shopping list. The current Fox alloy wheels are nice but.. one of the rear wheels is not very round, they are also drilled for BMW hubs, i.e. 5×120. The rear hubs are Audi, 5×112 so I had to slot the wheels to make them fit.
So I want to replace them with a staggered look, 8″ x 17″ rear wheels with Audi PCD and the front 7.5 or 7″ x 17″ BMW PCD
Limited Slip Differential
The car has an open differential, that means only the rear left wheel drives the car. So when the rear wheels spin, only one moves, this makes the back of car very unstable as it spins them in all gears if I am too hard on the throttle.
I have bought a universal LSD, however I don’t want to fit it into my gearbox, just in case it ruins it, so I am going to buy another Audi diff to work on. This is a job for the summer
Front wheel Geometry
I think when I made the front hubs I made a mistake, as the steering is very similar to a shopping trolley. So the most pressing and urgent job for this weekend it to sort that out.
Today I sorted out the front geometry, well the tracking (wheel alignment) and caster anyway. The caster was neutral which meant the steering was horrible. I had meant to add 3 degrees caster, instead I added 3mm caster, so the car handled like a shopping trolley. the 3 degrees is the angle from the wheel pivot to where the lower balljoint connects to the hub. I was advised that 5 Degrees would be better, and 5 degrees on my uprights is 9mm from the centre line..
To set the tracking I went old school and made a jig.. 72″ pieces of wood bolted to the front and rear centre lines with string running parallel the length of the car. Then it is just a simple job of using a tape measure and adjusting the tracking. I set the alignment to 2 mm tow in.
I have also replaced the rear springs with some longer and stiffer ones. This has raised the rear slightly giving me more room on the rear arches.
Now the car drives in a straight line and the steering feels epic!