Lovely car, new wheels look much better

That's really tidy esp the engine bay and engine details . Love the look of the wheels makes it look tough.

Thanks for comments guys.

Yesterday I replaced my rear beam bushes from Poly to Nylon, and corrected the rear toe, happier with the place the car is in now.

Road noise and "graininess" is worse which I kind of expected, however some impacts and undulations on the road actually feel a little nicer, the "two stagey" steering response I was getting on swept steers is still there however drastically reduced :) lift off oversteer still occurs, perhaps at a slightly faster rate but if you're expecting it it's fairly easy to quickly catch with around 1/3 of a turn opposite lock.

So all in all a positive change.

Even though my cambers and symmetrical either side, the LHF wheel sits closer to the arch than the RHF, and consequently catches slightly when it's heavily loaded. I do feel although I may well need stiffer springs for track, but I think looking at gaining more arch clearance will be my better option to begin with.

All in all a good change... Next up will hopefully be ironing out a few issues with the subframe, although I modified the sump before I'd still prefer a smidge more clearance as it can catch, and similar with the exhaust manifold, so they'll both me coming back off, and perhaps modifying the front brace on the subframe as opposed to doing the manifold... To shorten the manifold enough to clear the frame would result in it no longer clearing the sump, so I'll have to have a look!

Then hopefully I'll obtain some material and make some steering arms, introducing each change one step at a time :)

No pictures unfortunately!

Hey all...

Not been up to much, been on holiday.

With these wheels I am now running, the rim catches the tension strut on full lock, so I have machined some steering 'lock stops' which sit inside the steering rack to reduce the amount of lock I have slightly, to stop this occurring. Obviously it would be an MOT fail, but if I were ever be in a situation where I need to get to full lock to catch the car, the rim touching and effectively braking that one wheel could have bad consequences, so now it won't touch.

Didn't do anything exciting with the rack, just a full strip down, checked it all out, machined and fitted lock stops, cleaned everything (including sand blasting the casing) and re-greased it all.

Also, the RHF wheel catches worse than the LHF, which I believe is partly down to the fact of only having one adjustable steering arm.

As you have to turn the steering wheel to set the RHF toe, then adjust the left, the rack is no longer central, so you have more lock one way than the other.

The next thing I will be making is rose jointed steering arms, which both sides will be adjustable, therefore the rack can remain central and I will have equal lock left and right. This isn't really critical on this style setup as the rack is a fixed ratio, however if it were a newer car a lot of them have a varied ratio rack bar, so for example the steering maybe a faster ratio around centre then slow down, so if this wasn't central the car would be different in response and feel left to right.

I have all the parts to make steering arms now, just finding time as I have a lot on again so potentially no updates for around 8 weeks :(

Nick

I'd almost forgotten you had this. Haven't seen it out for ages. Upgrades looking good though and like the new wheel and tyre choice, proper motorsport look :)

Hey Hey,

 

Long time no update. 

 

Not been too busy but life gets in the way.

 

So last update I mentioned rebuilding a new steering rack and making new steering arms, so I got on with that..

 

CDS tube, with a boss fillet welded to the end, which I then machined the weld flush, to allow me to slide tube over the top to weld around to add strength

 

 

Passenger side arm together, with a hex welded on for easy adjustment

 

 

Drivers side together

 

 

Then it was just a case of a lick of paint and machining up some adapters to make the rose joints an 8mm mounting hole instead of 14mm

 

 

I also had exhaust manifold clearance issues with my stage 3, and also like the idea of being able to remove the exhaust manifold without needing to lift engine/drop frame.. so I made up a new front section

 

 

The sump I previously modified wasn't quite enough...so tweaked it a little further..

 

 

Also, due to having a lot less rebound travel than standard, I decided to modify my top mounts so they cannot drop down if the car gets wheel lift, so welded some tags on which will then allow me to bolt them through the top of the front turrets..

 

 

You can see here how much more clearance the front of the frame now has..

 

 

I also got a front turret brace, and stole @RyanC's idea of a different brake reservoir cap..

 

 

Also changed my springs for stiffer as previously mentioned, I'm useless at taking photos, but heres my rear spring/damper assy's ready to go back on, although the dampers need a rebuild as one of the adjusters doesn't effect rebound damping as it should

 

 

Once I bolted it all back together I wanted to measure to see where my front bumpsteer was at, and see if anything could be done to improve on it.

 

For those of you who don't know, bumpsteer is essentially the toe change through the wheels movement through its suspension travel.

 

Ideally I'd like zero bumpsteer, or perhaps slight bump toe out, so as the wheel goes into compression it toes out slightly which will help generate a small amount of understeer as the car rolls when cornering. 

 

But anywho, I got a few bits together, and made a spreadsheet to help me work stuff out...

 

 

So, whats going on here is basically:

 

A flat plate mounted to the hub, with lines scribed at 10mm intervals

Front springs removed, and damper bolted in place, I set the ride height to its 'normal' height

Set two DTI's on the centre line of the plate, and a certain distance apart (this is needed to convert into degrees later on)

 

I then recorded the change of value on each DTI gauge, and subtracted one from the other to create a steer change in mm - due to the fact the wheel moves in/out with wheel travel, camber change etc using two gauges means you can get the change between the two, to get a toe change figure

 

I then recorded the gauges in 10mm increments into both compresison and rebound

These numbers are then easily converted into degrees with some basic maths, then you can plot toe change against ride height on a graph and solve the graph for a bumpsteer value

 

I knew it would likely be a bad result, but I was surprised at just how bad it was, for a start I had a LOT of bump toe in, the opposite way to what I wanted, however it was a nice linear bumpsteer 'curve' which is nice, although it was only tested through a 60mm sweep (+30mm / - 30mm) 

 

I then set about trying to correct, or at least reduce it. I lowered the inner steering arm mounts by 18mm, which reduced it by 11deg/m each side (11 degrees of toe change per meter of wheel travel) which is a pretty poor ratio for correction, which is just down to how long the steering arms are. 

 

You can see on this pic the before and after, and the equation of each plot, which multiplied by 1000 is the value in deg/m

 

I will be looking to correct it further, however it needs another 40+mm of adjustment, so it may not be possible to correct as far as id like. 

 

Other than that, I have redone corner weights and geometry, including raising the rear heights by about 5mm to previous. Spring rate wise I increased the rear by 25% but the front only by 16%, or there abouts, so the car is more adjustable on throttle and more 'hot hatch' fun, like a 205 GTI or similar...

 

Hoping to do a track day some point before the end of the year, but who knows!

 

Nick

 

Excellent work as always, and nice explanation on the bump steer measurements. Even I could get my head around that.

Thanks mate

Is this build still going on? Read it multiple times it's that Good!

On 19/10/2017 at 17:44, Mikecoupegt said:

Is this build still going on? Read it multiple times it's that Good!

 

Yeah man.. need to fix images and do a big update...

 

Its now got a G40 charger on the AEE, with ITBs still.

 

Not mapped properly yet, just ironing out some teething problems first! Hopefully it will be in a state to run at spring fest next year!

That's sick! Can't wait to see the update man.

Come on Nick! Update us!

Right, long overdue an update.. and to be honest I've lost track of what I've done.

 

So heres a few things from memory!

 

Earlier on I posted about measuring bumpsteer & trying to fix it... so I quickly designed a new rack clevis to enable me to lower the steering arms, but also adjust each side individually..

 

 

Which after a bit of playing around it ended up like this (values are average across the axle):

 

 

Have fitted a 6n2 GTI rear disc setup...refurbed calipers etc..mainly because I wanted a better wheel bearing setup!

 

 

 

Also attended the Polo Social earlier this year...nothings changed & looking pretty sorry for itself! Really needs a good clean...

 

 

The other main thing I've decided to do was supercharge the AEE because I was bored. I'm not really after mental performance or anything..just fancied messing about!

 

So engine setup is as it was, other than fitting a decomp plate so the CR is now about 8.2:1.. and bodged together a plenum using a 20vt inlet manifold...

 

Inlet flange side cut off, & machined square..

 

 

Made an adaptor to fit a G40 BRV..

 

 

Welded internally, skimmed & pressure tested..

 

 

Skimmed inlet manifold..

 

Test fitted..

 

 

Also had to modify a G40 engine mount to fit my block...took zero pics. And the exhaust manifold.. test fitting stuff:

 

Machined an inlet stub for the charger...

 

 

Got a new alloy rad & forge intercooler..

 

 

Smashed stuff together...

 

 

 

Its all a bit cobbled together at the moment. Stuff needs changing and improving, but I wanted to test how the G40 worked with ITBs etc first. 

 

Will probably make up solid boost pipes and stuff eventually and change a few other bits and bobs around.

 

Have done about 600 miles so far...mainly messing around mapping. Running a standard charger with a 68mm pulley, it holds about 6-8psi boost through the range and pulls reasonably well.

 

Going to do a bit more mapping first then take it somewhere for fine tuning on a rolling road.. not going chasing mad power or anything, expecting around 150-170hp.

 

I have missed out literally loads of stuff I've done..but I lose track!

 

Merry Christmas.

 

Nick

Probably be a queue forming for rack clevis 

 

Excellent build

On 26/12/2017 at 19:17, kiran_182 said:

Probably be a queue forming for rack clevis 

 

Excellent build

 

Funnily enough I was thinking the same.

 

Excellent build as always! You can tell you're an engineer! 

Haha thanks...im not an engineer, I can just cut shit up and stick it together...ish 

Very impressive work..

That is super nice excellent work

Very nice!