Back to roots

I've neglected the GT5'ness of this blog for a while, so here's a clip:

But that's OK, we've had a poor turnout of late to race nights. If we can't muster much this week we'll scrap points and just work our way through the season, it'll save me a load of time. Time which I can spend unbolting plastic trim. Oh yes.

I know kung-fu.

Well, I might as well, I now have it reasonably figured how the diff works on my car(s) and what I can do to resolve the issue I have.
What's the issue I have?

1. I have a manual car, with welded diff - not drivable.
2. I have an auto car with open diff - with crazy ratio.

Ready?

320i ratio for a manual car is something between 3.45:1 (rare) and 4.27:1, the ratio for an auto is 4.45:1

What does this mean, the number of turns the prop-shaft will do before a wheel completes a revolution.

So, basically if you're cruising at 100Kph in a standard manual (diff) and fitted an auto one, you'll be going slower, or rather revving higher to get to the same speed. I.e. lower ratio diff. Excellent.

Got it? It's all in the gearing. What's confusing is that the gearing is largely outside of the diff bit.

Here's an interesting video on how diffs work:

Fascinating I think you'll agree.

So what does this all mean (I'm losing track myself actually)?

Well, I've been looking at these online, ebay has them:

This would fix my welded diff, but for $500 (the same pretty much I spent on Ron Burgundy) I reckon I must have the parts.

Consider this video... it's how a diff gets welded up :

What you're seeing is a tiny little collection of gears with a huge mo-fo gear around the outside.
And here's the money shot - that little set of gears is the bit in the pic above, the $500 part.
And... the gearing/ratio is set by the big ring round the outside.
I can use the outside gear from my manual car, on the auto good diff.

With me?

Action time:

1. Pull off my locked diff.
2. Pull it apart, check that it's welded in the 'tiny bit'.
3. Pull that out.
4. Pull out the auto-diff.
5. Pull out it's 'tiny bit' that we know is open and works.
6. Affix manual gear ratio to the auto 'tiny-bit'.
7. Reassemble as the diff for my good car (that's not the auto, did you see the woosh comment below?)
8. Never mention diffs again.

One thing I have to consider, is what the ratio is for the manual car - if it's 4.1 that's OK. But I'd like to have lower ratio gearing.

Why? Well you're into GT5, shorten the final drive in transmission settings and see what it does to your car's acceleration.

The one massive caveat to all this is how the ratio is worked out. But, ebay has the outer rings too, so I can replace them if I have to!

So there it is, I can buy the parts to sort my world, pull apart two diffs and probably get there. And in any situation there are ways forward that aren't going to break the bank.

Wear on the diff in the manual is going to be a factor - it's been welded after all. So I may invest in the ratio above and have that onto the auto diff, and ditch the risk of the track trashed one. Sound thinking actually.

I need a beer.

[Update]
This page has had a massive update. Why?
Well, like a proper religious zealot I had it in my head that the ratio was the divisible number. I.e. the bigger the number the higher the final drive gearing. But it's not, it's simpler than that. It's just the number of turns of the prop shaft before the wheel makes one revolution.
And it's been hard to change my way of thinking, I had a belief system around it, a sound hypothesis and generally made everything work with my world view.
I can't stress how confronted I was when I did the only thing that I knew would convince me... that being on the removed diff I turned the prop-shaft and looked to see if the wheels would spin faster or slower.
Slower obviously.
And now, as an enlightened soul I can see it's obvious. The gears are small to big... fast to slow. Easy.

Lowering the tone

I came home to this stuck on the back of my 'new' car...

Harsh. But fair.

I can explain...

I think that this picture needs some justification...

Yes, yes it is another BMW E30 320i. And in this picture it looks half decent.

That'll be the half closest to the camera then.

$550 has bought me a spares car!

What's good about this car:

• It drives!
• Open, and working Diff.
• Rear disk hub (so we can replace that)
• Working radiator - funny haha story to follow.
• A myriad of little bits of plastic that I needed to buy.
• A clean/straight bonnet, albeit in redish fade sort of colour.

What's not good about this car:

• Auto box - and that means that it goes with a bit of a woosh. 
• Without actually wooshing. Gutless blob this car is sadly.
• Tan interior. Somewhere in there is almost certainly a medallion.
• Rust - quite a bit as it turns out. If I pass wind in the car I reckon it would punch a hole in the floor.
• No brakes, well, some, on one wheel. But that's OK, not like it goes fast enough to care.

But you want to know about the radiator...

Picture the scene. I've removed the fan, that was held in with a couple of cable ties - so time to refit.

Being me, I decided to 'ease' the drill through the bulkhead so I could put brackets in, and then blind rivet them in. A sound plan, and all was going well.

Until the last drill hole, in which I eased a bit too far. A trickle of kryptonite water and a dead car.

Damn.

In fact, if only I had a Dam, cos there's quite a lot of that green stuff everywhere. Even the roaches are steering clear of the floor in my garage at the moment...

But all is not bad. In doing this I've reworked the cooling pipes and figured out where the magic third cooling pipe goes (back to the previously defunct header tank, I had two).

And it get's better. Dona (as in Donor Car) has the gift of sensors and radiator so soon I'll be back to where I was a month ago. Yeay.

So, as the great JC would say, "Sit Rep"... now have two cars, or rather 2 2/3's of cars, so about 1 1/3 cars or something in the final analysis.

Anyone know anyone who wants the rusty shell of a BMW E30 in about a month's time? They'll need a crane...

Race night tonight

Folks don't forget it's race night tonight.
Although we had connection woes last week, the few that made it on the night had an excellent race night in the GroupB cars before it all went to toffee...

There was enough of us there to make the results stick, so we'll take it as the official results:

1. Andrew

2. Callum

3. Evan

4. Paul

We did have some serious drop outs past then, but did manage one good race.

I do encourage all of you who like and want to race to come and join in, even if you're late to the party (Chris, thanks for making the effort last week too).

Sunset Season Starts Soon!

And if you've read that out then you'll need to wipe your monitor.

The first official racing of the season starts this week. Have I got your GroupB car?
I think what we'll do is see who has what on the first race and lock that in. Certainly I've changed my mind a few times, and am back at the S14 category again - that NSX just wasn't fast enough.

So to business, this first race night is a return to some classics really. I hope we enjoy the nostalgia...

The Track(s)
GroupB - Dirt/Toscana  - this is the in house Toscana Dirt track, if you're in a 4WD then you're in.

First championship race is at Leguna Seca in the GT590/4 cars - this'll be a blinder, that track is well suited to these cars. Interesting factoid, all the apexes are marked on that track - no excuse for missing the corner!

Second race is Le Mans, in the tried and tested Exotique (587pp) cars. Those of us who did a test'n'tune last week will be well ready for the race night in these cars.

The Car(s)
GroupB - Get one sorted! There are a few lists floating around, so ensure you're not doubling up with another racer, but I think we'll be fine.

GT590/4 - Question here is if the Honda will be as dominant. I'll be in an NSX I think, it's reasonably stable and just about the only thing that'll keep up with the Weismann.

Exotique - As we found out last week, ballistic fast (as fast as the GT590's in fact) but not able to stop in any measurable way. So find a car that'll crank it's way around Le Mans, which thankfully doesn't require more than four heavy breaking zones.

Official Details

GroupB
Host: Andrew (Andyc709292)
Lounge: FCT GT5 Andrew
Date: 19-September-2013
Track: Toscana Dirt
Start time: 9:00 PM
Laps: 5
Cars: Chosen Season Car
Tyres: Dirt
Boost: High/Low

Championship Race A.
Track: Leguna Seca
Start time: 9:15 PM
Laps Per Race: 5
Cars: GT590/4
Tyres: Race Medium
Boost: Low/Off

Championship Race B.
Track: Le Mans
Laps Per Race: 3
Cars: Exotique
Tyres: Open
Boost: Low/Off

Good  racing folks!

Action Shot

Evan came up for a working day on the BMW on Saturday...

Sort of got a lot done, but sort of didn't, overall I'd say win.

The day consisted of:

• Starting the car - Evan hadn't heard it run without "hunting for idle".
• Talking about the front of the car - all the bits that are toast are off now, find and replace time.
• Swapping out the track rod on the LHS front. This looked to be a pig but wasn't once we had 'the persuader' (tm), a 32mm spanner to undo it.
• Figuring out how to do the fan, it's just engineering now.
• Talking a bit more (a lot really).
• A compression test - consistent 130psi across all six, which is not factory standard, but consistent is good.
• Deciding to take the rear hub off to sort the two sheared wheel nuts.

This is where we ran aground. Many sweaty hours trying to drift the hub off the axle have proved fruitless. 

To cut a long story short I now posses a reasonably expensive single use device which may do the job. Time will tell (a lot of time told us that it wouldn't work without it).

Once that's fixed I can actually drive the car, albeit with a locked diff and ruined bushes at the rear, which I will do to make sure I have all the gears I should have. 

I can't wait.

Special mention to the Matilda Garage near Beerwha too - thanks for the Commodore Resting At Peace - and the new battery. (in joke*).

I'll maybe post up a pick of the old track rod, if only to show the healthy bend in it... This car has had a hard life.

(* You too can have your own personal in-joke, cost, one day of greasing up with Andrew).

E30 'Sit Rep' (or Why I'm glad I didn't buy Italian)

So I've just spent an hour on the BMW.

And, in that time I've fitted the wing mirror controller (electric wing mirrors) and refitted all the drivers door bits, complete with the new OEM handle, which is a bit flappy but will more than suffice for now.
Behold:

Bonus points is that this car has central locking no less. And it works! This is why I am glad it's German and not Italian - an Alfa would have burnt out in a shower of high voltage sparks by now.

It's not all roses though, for some reason once ignition is off, the windows stay active - I can't work out if that's timing (very trick and very unlikely) or bad wiring (very likely). 

And, someone sent me a pic of this car in Brisbane - I pretty much aspire to have my car look like this

Albeit with different rims, though they do look nice don't they.

Finally, I am having second thoughts on pulling the gearbox off - the more bits I niggle away at and realise they're not too bad I wonder if it might be prudent to have someone do the whole thing in one hit. I'd be looking to:

1. Replace rear main seal.
2. Lighten the flywheel.
3. Replace the clutch.
4. Replace (with nylon bushes) the prop shaft & diff bushes.
5. Replace (maybe nylon) the rear sub frame bushes.
6. Replace/recondition the diff.

Quite the collection of tasks really, and a lot of propensity for messing it up big time - and this car is dangerously close to gender/name stakes at the moment.

Win

Dear diary.
Today I set about starting the car* for the first time. It's been sat in my garage weeping oil for a bit, and it's been sat with the previous owner for longer. Something is broke in the starter circuit.

Roll forward a mere five minutes...

Dear diary.
It lives!

So what was that all about then? Well, the previous reckoned it was something fundamental and was going to take some heavy diagnostics to get it working. As you'll have heard above, turns out that it was the relay up under the dash. What does the relay do? Dunno. But in pushing it in I shall no longer be using the term "Hunting for idle" or "not catching when you floor it".

My guess is that it controlled the ECU, and without it it both stopped it starting and ran the engine in default mode.

I didn't run the car much longer, it needs an oil change before I go much further. But, the list of things to worry about has just got measurably shorter.

*Car needs name.