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Discussion starter · #101 ·
Method behind the madness....

PCI arms (with 2x RJ's): 4.265kg
DC5 hubs without RCA's: 6.765kg

SRT arms (no RJ's fitted): 2.165kg
EP3 Grp.A hubs with RCA's: 6.245kg

Up to around 31.5mm wider track per corner than a DC5 conversion, reduction of around 2.5kg per corner of un-sprung weight plus no additional weight from having to get bigger brake carriers machined for the DC5 knuckles.

Another 5kg+ off the car, at the end it's hard to get rid of weight from, and it's un-sprung... What's not to like...:D

I'll get this lot fitted tomorrow so we can get the ARB brackets welded on along with brackets for potentiometers then it's strip and off for some powder coating. Front suspension done!
 
Ok, so that would mean 5 in total then, one on each primary then the usual one on the collector. Don't see the point of switching to single after map as that's additional cost for another sensor, additional wiring and you've got 4x empty boss in the primaries that need filled unless you want to reduce lifespan of those sensors for no reason. Surely for closed loop you can still retain the four on the primaries (this would run from averaging all four) and retain data logging per cylinder?
Doug, initially you would calibrate the engine with your lambda probe in the general collector (all 4 cylinders) and use the usual trim functions available om the M1.

When you have the fuelling where you want it you can then tackle the individual cylinder fuelling, move the lambda to cylinder 1 exhaust runner, run it up on the dyno through the rpm range and note the fuelling differences (+/- %) over the desired at the various rpm positions.

Move the lambda sensor and repeat the process for cylinders 2, 3 & 4. This will give you the +/- % fuelling differences for each cylinder.

Put the probe back in the general collector.

Add in or remove the % of fuel needed on the individual cylinder trims in the ecu based on your results.


Individual cylinder EGT's are also another great addition, cylinder fuel trims can also be added or taken away to get them all running the temperature. Motec also do an EGT to CAN module that works very well, I have one on the evoGTR.
 
Discussion starter · #107 ·
gets there :)
It this a safety cell around a swirl pot & fuel pump?
Bulkhead for dry sump tank as per regs. I'll probably skin the cover with nomex / carbon to shed a little weight and still comply with fire proofing / bhd regs.

Tank was originally sat infront of the gearbox mounted to a chassis leg which isn't ideal for crash protection or weight distribution. Moving it back wins on both fronts at the expense of slightly longer hoses. Plan is to run them under the sump against the flywheel cover, checked for clearance given the engine is sitting 25mm lower than stock and should be good. Front splitter / under tray should give some protection to the hoses if I end up off road!
 
Glad we both subscribe to that belief? I mean I don't look for it to happen.......:oops: :unsure: Got some more "poor boy" stuff coming up for you. Thanx for being a good influence on me.
 
Discussion starter · #114 ·
Fuel tank finished and boxed in, air compressor / receiver boxed in...

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Tank is internally baffled with a small sump on the bottom. Hopefully I'll get away without a lifter pump but I'll suck it and see when it hits the track. Boxes have been made in such a way that remaking them using CF / Nomex should be very straight forward.

Next up, seal all unused bhd holes, rear arches, exhaust system (including manifold) & ARB mounts for front arms. That should be all metal fabrication work complete then it'll be onto some composite work before ready to prep for paint.

Any progress is progress!
 
Discussion starter · #116 ·
Rear arches done. ARB link brackets to do and that's job done (for now) on the welding side of life.

Lots of work to do even without an engine in it...

Inside of the shell and engine bay prep'd / painted and start putting in all fluid / air lines up to bulkehad, mount all the electronics (ecu, PDM, dash etc), fit potentiometers to the suspension, have new caliper brackets machined for the rear, swap the EP3 / DC5 rear hubs over, convert the fuel tank / compressor housings to carbon / nomex enclosures, sort the fit of the rear arch extensions, measure / cut the rear bumper for diffuser then convert to carbon, start flat floor prep (should be doable without exhaust in place), convert rear lights to carbon blanks, lighten door & boot hinges, fabricate skirts incorporating air evacuation from front arches, inner front arch covers, convert scuttle panel plastics to carbon, measure for driveshafts, get the spare block / head cleaned and fit dry sump for routing hose / locating filters, full brake lines, spec cooling system to get rad / pump mounted and allow front bumper prep for ducting, modify front arches for air evacuation, etc... etc... etc. Quite a bit to do even without an engine to be honest!

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Amazing project news Doug, the new wheel base will give quite some traction. Here in Europe (main land) we have also some body widened EP3's like the one of Mr. Ljubijankic.



I don't like the tune (too rich, transients are even worse) and the lateral oscilation of the drivetrain, which is likely based on tune and play of the drivetrain, but the traction of that car is not bad. I see a bit of understeer, but the driver steers very hard and counter correct if necessary, which looks sometimes like digital set steering angles.
 
Discussion starter · #118 ·
Indeed. Think we'll be around +30mm rear with room to tune with spacers and front up to +55mm. 9" is optimal for traction vs drag according to the race engineer but will need to see how well we can get the power down. Been a big focus on using the right components to gain track width whilst retaining proper geometry. Doing this without going to a touring car setup needs careful design / attention. (would be illegal for my class due to rear arb cut outs in the wheel well / chassis mod with wheel centres not for passage of exhaust or fluids)


Still a long way off as I'll need to take loads of measurements once it's rolling / built to revisit springs / valving, ARB sizing and also disc / piston / MC sizing for brakes but getting there. Fingers crossed start of next season or mid season is a green light!
 
What an awesome build. I can’t wait to see you out there driving the thing. I’m sure you’re feeling the same way haha. Great stuff here. If my build is even a fraction as good as yours will be, it should be an absolute killer out there!
 
Discussion starter · #120 ·


I don't like the tune (too rich, transients are even worse) and the lateral oscilation of the drivetrain, which is likely based on tune and play of the drivetrain, but the traction of that car is not bad. I see a bit of understeer, but the driver steers very hard and counter correct if necessary, which looks sometimes like digital set steering angles.
My ears are bleeding after watching those... :LOL:
 
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