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R500_WKD

Nigel's Varioram-Powered Über-Tractor

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Thank you Mark.

 

Anyone else out there got a different opinion?

Nope, what Mark said. My car is set-up the same and a 911 racer mate paxing said my car turned in better than his race-car :) (Druids at Brands)

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The bigger the ARB, the more work you are making that axle do. So, bigger front ARB makes the front do more work and increases understeer. Bigger rear ARB gives more oversteer. So, yes the advice is somewhat correct in that if you go bigger on the rear ARB then you have a car that is more willing to rotate (ie, oversteer) or, put another way, more willing to turn in.

 

However, turn in is usually describing something different from under/oversteer balance - which is really what ARBs are doing, ie., tuning the under/oversteer balance. Turn in is usually more a result of alignment as Mark says. Bigger ARBs don't really hurt turn in, but if you took it to extremes, like with no rear ARB at all, then it would create a strange balance. Although, to show how insensitive these cars are to ARBs, some 911Es were sold with just the front ARB and no rear, 911Ts often had no ARBs and 911S had 15mm front and rear. All worked out ok.

 

The torsion bar sizes - 19/26mm - are fine for fast road. You could go bigger, but you sacrifice ride, though ride is more a result of shocks than springs, up to a point of course. If you are buying ARBs, then I would go bigger than 16/18mm personally, however, those are quite period sort of sizes for a 70s inspired car. They are not wrong and you can fairly easily change them later. Certainly for road use and no track, they are a fair choice.

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Thank you for all the advice guys. Sounds like I should go a bit beefier that 16/18. Not sure that for the end use I have in mind 22/21 is the right answer either, sounds a little too track orientated. Perhaps something like 20/20 would be a good compromise.

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22/21 ... sounds a little too track orientated.

 

Not really too track orientated when it was standard for production road IBs after '85.

 

 

Mark

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23/22mm here with Boges and 1160kg weight - perfect for my road use and no less compliant than before.

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Here's one for the more practically minded!!!

 

The engine was a Tiptronic. Now being mated to a G50.00. The benefit is I'm not scratching my head wondering whether or not to go lightweight flywheel setup and bin the heavy setup, as there is no heavy setup, so light weight it is.

 

The easy thing to do is go straight to Patrick and ask for his lightweight clutch and flywheel setup. It's been done many times before, it all appears to work well and is balanced to within an inch of it's life which should minimise the lightweight chatter that people complain about. I know it's all going to fit and work. It is however eye wateringly expensive.

 

The other route is to make up a light weight setup. But it all looks dauntingly complicated. And I don't really know what I'm talking about.

 

The Indie is keen on going down the Patrick route, but happy to take the OEM route to keep the budget sensible.

 

What do the collective think in terms of how the finished product will differ, Patrick vs OEM and does anyone have a list of required parts for the conversion if I chose to go that way?

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A wet and 'oriole Saturday in Essex, so a bit of web research done on this issue.

 

How does this look as a shopping list? Do we think that clutch might be a little too stiff? Anything else I'm missing?

 

for a 964 w/ G50 , some of the parts have been updated to 996 or 997 part #s

RS LWF 964 102 239 31*
RS PP 964 116 028 03*
RS disc 996 116 015 32*
RS starter ring gear 964 114 143 31*
RS guide tube 950 116 813 30*
Rear main seal 999 113 426 41*
Flywheel bolts 928 102 151 01*
PP bolts n 014 715 3*
Release bearing 944 116 080 01*
Pilot bearing 931 102 111 00
Clutch release arm 997 116 086 90

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I have late Carrera ARBs on my SC. Had extra holes put in the tabs on the rear one too. It's a nice upgrade for a road car.

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I'm back.

A couple of years delay while a few issues sorted out. But this year could be the year the Uber Tractor sees the light of day...

 

IMG_1086[1].JPG

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1 minute ago, R500_WKD said:

I'm back.

A couple of years delay while a few issues sorted out. But this year could be the year the Uber Tractor sees the light of day...

 

IMG_1086[1].JPG

Looking good, 2017 is your year!

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I do like your car Nigel :revs: Now hurry up and finish it! :P Is there much still to do and are you finishing it or is it still at the same place?

 

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It has moved, hence the progress. Interior should be going in over the next month, everything together, just need the finisher to find time to get on with it. Bell housing shortened and diff going into gearbox. Waiting for parts to turn up from Patrick Motorsports so we can mate it to the engine and put it in. It has been horribly slow but has suddenly gathered momentum again. All good things are worth waiting for!

Yours is looking good. Keen to find out how those wheel spacers work out. I am running 15mm at the moment front and back. Not going to mess with it until the engine is in and it is half set up but suspect I will need another 20mm at the back and 10mm at the front. Worried about wheel bearing stress, but if your runs well on 75mm I have nothing to worry about!

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After a very long break the project is back on the go. 'box shortened and back on the engine and going in very soon I hope.

I am missing a set of rear callipers. I thought I had a set found but was let down unfortunately. Does anyone know of a set of rear 930 callipers that are available to buy?

Thanks for the help, Nigel

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5 minutes ago, R500_WKD said:

After a very long break the project is back on the go. 'box shortened and back on the engine and going in very soon I hope.

I am missing a set of rear callipers. I thought I had a set found but was let down unfortunately. Does anyone know of a set of rear 930 callipers that are available to buy?

Thanks for the help, Nigel

Good to hear, hope you get it all finished this time ;)

930 callipers are a bit like dragon balls nowadays, kinda hard to get your hands on. I wonder if a set of repro ones might be a better bet? EB do some RSR as a full set: https://www.eb-motorsport.co.uk/productinfo.asp?id=264

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Just now, jevvy said:

Good to hear, hope you get it all finished this time ;)

930 callipers are a bit like dragon balls nowadays, kinda hard to get your hands on. I wonder if a set of repro ones might be a better bet? EB do some RSR as a full set: https://www.eb-motorsport.co.uk/productinfo.asp?id=264

Is that a typo Jev? £7900 for 4 calipers. Must be made from melted down dragon balls! 

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4 minutes ago, Busybee said:

Is that a typo Jev? £7900 for 4 calipers. Must be made from melted down dragon balls! 

Ha no, I think the RSR are unavailable so for the racers there is only 1 option.

Few more clicks and looks like Rose Passion can get you a new calliper by tomorrow for £1300 so maybe your local OPC could do similar?

https://www.rosepassion.com/en/cat/piece/P31162

webP31162.jpg

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If I was a Dragon I would put a pretty hefty price on my balls too. 

Hoping to find a pair of rears that are a little more reasonable than that!

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8 minutes ago, jevvy said:

Ha no, I think the RSR are unavailable so for the racers there is only 1 option.

Few more clicks and looks like Rose Passion can get you a new calliper by tomorrow for £1300 so maybe your local OPC could do similar?

https://www.rosepassion.com/en/cat/piece/P31162

webP31162.jpg

Thank you Jevvy, I will investigate. 

Forgotten just how helpful this forum is!

Nigel

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