Sam's build thread

[sambb]

The story of this build thread begins with the demise of the car that I've had for the last 3 years. It was rear ended by a landrover who's texting pilot never even touched the brakes, hit me at about 50kph and sandwiched me between it and another SUV. Bent chassis rails that caused the rear quarter ripples and all the other damage meant that it was written off.
So I'm now the proud owner of two silver Polo's, one's a wreck in the garage and the other is Seangti's old daily. Between the mods/bits that were on my car and a few bits that are on Sean's that I didn't already have, I'm hoping that the sum of both cars will soon equal a pretty good streeter/hillclimber.
So before the build can begin the strip out of the other car has to happen first. Then when I get the garage back the hard work with this car will start with swapping all the bits across, gearbox swaps etc.
With the benefit of hindsight I'm going to do things right this time and start with an LSD. I'll post soon with where that's heading and what I'm considering, but figured I'd get this started for now.

sam

[sambb]

So there are 4 diffs that I've been considering. Two are Torsens - Quaife ATB and Wavetrac. Out of those I'd be going for the Wavetrac due to it apparently being better at remaining 'locked' compared to the quaife unless there's a stupidly cheap Quaife for sale somewhere. The other two are plate/clutch LSD's - a 1 way SQS, and a 1.5 way Kaaz. I've been a bit put off by the idea of a 1.5 way. While it might be the go for fast sweeping tracks with long braking zones I've been told by a Brisbane diff/gearbox specialist that in the really tight corners of hillclimbs I'd probably find that the 1.5 way setup would cause understeer problems, and that the 1 way would be spot on for that kind of driving.
So out of plate SQS vs torsen Wavetrac it'll come down to longevity. Plate diffs need adjusting since they inherently wear like any other clutch. Actual full blooded driving time in hillclimbs and sprints is short so given that, If I can get some clear answers on the min/max time for when this kind of diff would need to be removed and serviced and I'm happy with that then i'll go plate LSD any day, but if they are far from set and forget then wavetrac it will be.

Also wondering what track/street guys have chosen with their clutches. Are most people running a standard organic full face clutch but with an uprated pressure plate or uprated clutches too? And with single mass flywheels can a standard cast single mass just be machined to be lightened or is going steel a must?

[Stuwey]

I had an ECS stage 1 - style clutch in my K04'd GTI, with a single-mass 14lb flywheel from memory. I've had a beer or ten since then! Pedal weight was light than stock, it was a pleasure to daily. A few extra vibrations, but that was all par for the course. I really don't know that going any tougher is going to get you anywhere.

I would have to agree on the understeer tendency of the 1.5 way diff, but that may also just be something that you learn to drive around and eventually be quicker anyways??

[sambb]

So you were running the Stage 1 clutch with the LSD? - that's where I was a little unsure regarding rating thr clutch. Power-wise I knew a stage 1 would probably handle it, but with the extra loading that having the LSD would put through the system I wasn't sure if at least a heavier pressure plate would be needed.
Were you running a 1.5 way limi or did you go with something else?

[seangti]

So out of plate SQS vs torsen Wavetrac it'll come down to longevity. Plate diffs need adjusting since they inherently wear like any other clutch. Actual full blooded driving time in hillclimbs and sprints is short so given that, If I can get some clear answers on the min/max time for when this kind of diff would need to be removed and serviced and I'm happy with that then i'll go plate LSD any day, but if they are far from set and forget then wavetrac it will be.

From a maintenance perspective, my mechanic only works on race and rally cars. He said the rally cars have the plate diffs serviced every season. For a track/street cars, he suggested ~3yrs would be reasonable for service intervals, but is obviously wear dependent and track time... Getting box in and out isn't too bad, drive shaft bolts usually the worst part if they don't cooperate. Though you'll be paying a mechanic/diff specialist to open the box.

[sambb]

I'll be getting the box out of the old car on the garage floor. I guess after that i'll know if I have the stomach for doing it again in the future. if not = wavetrac

[sambb]

sorry another clutch question. Does Stage 1 eg from ECS or somewhere like that, just mean standard run of the mill single mass clutch kit or is it uprated over the normal sort of VR6 kit you'd get OEM?

[sambb]

I'd made these rose jointed droplinks up for the RARB up two days before the crash.

PS if anyone want to buy a whiteline 20mm RARB let me know - i'll be pulling the one off the old car in the next couple of days. Has to be Sydney drop off/pickup and cash though.

[sambb]

Went down and spoke to a engineer/racer today and had a good chat about my idea to bend the rear twist beam in at the hubs to achieve just a touch of rear toe in. Unfortunately he said that whilst twist beams can be very soft in torsion they can be very stiff laterally. He said sometimes they will deflect miles and then literally go straight back to where they started (lots of memory) but then if you go 1 mm beyond that, they will remain there irreparably - impossible to predict the outcomes. He basically said to achieve what I want i'll have to go with something like the whiteline toe shims (problem is they are out of production) or strategic washers under the stub axles and lots of measuring.

So if anyone out there has whiteline toe shims sitting on a shelf or on their car and they didn''t do it for you, please give me a yell!

I forgot to ask him about boxing the rear beam so that'll be a chat for another day.

Incidentally he knows of/had raced against Jordan Cox the Civic guy who's tearing it up in improved production at the moment. Apparently $20k + has been sunk into the suspension/chassis of that thing. Think i'll be sticking to small budget hillclimbs rather then circuit stuff when you hear dollar amounts like that being thrown around. nuts!

[HaydEn]

Eibach still sell shims, $40 on ebay.