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MG ZR ZS ZT Technical - Modifications for the ZS/ZR?

Modifications For the ZR/ZS

I was just wondering what mods people have tried or heard about. I believe that you can up rated the brakes using a kit from AP racing.

Four or six pot callipers, do you have to lose the A.B.S? I was also wondering if anybody has tried the limited slip dif as used on the BRM 200?

Has anyone tried new make of tyres? Or do you know of something "Interesting"?

Cheers
Mega.
Mega

Mega,

> I was also wondering if anybody has tried the
> limited slip dif as used on the BRM 200?

I looked into this. Although my ZS180 puts the power down well, the PZeros lose a lot of traction below ~5C making it difficult the pull out on to major roads without (unintentional) manic wheelspin. The 'box in the ZS is the PG1, which has been fitted with a Torsen diff in other applications. However, the list price for the diff is over £500 exc. VAT - and then you have the labour to fit it, which is not insignificant apparently. I figured that it was going to be nearly £1k - which was more than I want to spend on it right now.

HTH,

S.
Steve H

what's the final drive ratio of the XS? and is there a Rover 600/800 application with Torsen diff with a ratio that's close ? If so, then a possible mod at a quarter of the cost maybe ?
David

David beat me to it, but the Rover 220 Turbo, 620ti and 820 Vitesse (?) are a more readily available source of Torsen diffs than the rare-as-hens-teeth 200BRM.
Rob Bell

My price was for a new diff - seeing as it is a new car, it seemed to make sense to use a new diff! I didn't get as far as checking final drive ratios available.

S.
Steve H

I got an e-mail forwarded to me from someone selling an entire 200BRM drivetrain. 900 quid all in, new unused. Not exactly cheap when you figure in the labour involved, but you do get alot for your money.
Rob Bell

Mega

Be serious - the car's whether ZS or ZR don't need 6-pots. My EVO VII has Brembo 4-pots (I have a 6-pot kit bought ready to fit but not required). These cars are awesome without mods - why risk invalidating your insurance/warranty for a "pinch" of salt??

PS. The basic driver whether Liverpoodlian or an Essex boy, wouldn't notice 6-pots or 10 extra bhp unless he is a track day "DRIVER".
Jerry Flint

> why risk invalidating your insurance/warranty for
> a "pinch" of salt??

Err, Jerry,

Weren't you just talking about buying a ZS/ZT-T and invalidating its warranty in another thread?

I'm all for letting people mod their cars should they wish - providing they accept the consequences on the warranty. Sure, 6-pots seem overkill to me, but some people might not like the colour of my ZS - to each their own...

S.
Steve H

Jerry
I was simpley trying to start the ball rolling, i never said go out and "six pot it". I would start by braceing the shell front and back. AP 4 pots brakes and some "Police mode". I would only buy the ZS/ZR if MGR have sorted the "Problem".

I know you have it in for me, i would knock it off if i were you. Next time you get to "V1" you will find that i have taken all the nuts off your wheels!
Regards
Mega.
Mega

Jerry,

I have an MGF Trophy with AP Racing 4 pots and a ZR160.

The ZR160 brakes, IMO, are crap by comparison. MGR should have fitted the AP's to the 160, IMO. We're talking peoples lives here.

Same as the folks at MGR should have talked to M. Satur about fitting stylish, functional roll-hoops to the TF. Or indeed as soon as they were available. For God's sake, it's peoples lives, not politics, budgets and bull sh*t.

Mega,

Go buy a ZR and enjoy, you're obesessed with seats and its crap. The seats are fine. Hire a ZR for a week, drive it, hard, and you won't be worried about seats.

The pair of you need your heads banging to together!

Chris

Torsen diffs come in two flavours, earlier ones which apparently have seen some reliability issues and more recent ones. (no I don't know the transition point or specific ID numbers) They are straight fits in all 2****** series gearboxes, which means all of the ZR, ZS range with PG1.

It would be good sense to go with a new LSD for a new car, which should aid long term reliability, as well as ensuring proper operation.

I actually went round Powertrain yesterday, only the K series production area though, and in the official info pack on the PG1 this short but informative piece is copied. 'The gearbox can be supplied with either a standard open differential or a Limited Slip Differential, presently Torsen.' I pick up the reference to 'presently Torsen', indicating both recognition of the Quaiffe alternative and whilst no one will talk about it, the same companies 6 speed conversions for the PG1. This desirable development hasn't gone unnoticed!!!

The same info sheet goes on to say, 'Including both present and past and overall total of 21 ratio combinations, 5 speedometer gear ratios; and 7 clutch lever designs for both hydraulic and cable operation can be called on to ensure the customers requirements are met.'

Currently there are 15 production vehicle variants of the box using 6 basic sets of ratios. Additional gearing variation comes from wheel and tyre combinations.

Finally it is interesting to note that the box is still made with the two torque handling capacities, 216Nm and 240Nm. The latter is fitted to the ZS180 and does indicate that this will be a limiter to the power upgrades seen with this car as the standard engine is rated at 240Nm. (ZT 190 incidentally is rated at 245Nm, but uses a Getrag gearbox)

A 330mm front brake kit from AP Racing has been available for some years (Kit number CP5200) with a 4 pot using 2x41mm and 2x38mm pistons to give a 'leading edge clamping effect. Expect to lose 1500 pounds to own one. Also this only fits under 17" wheels, but is brilliantly effective as this is (I think) exactly the kit fitted to the PTP/Janspeed 200/25 MG concept car. This retained standard ABS without any problems, and the rear discs were increased to 280mm with spaced original calipers.

Rog
Roger Parker

Thanks Rog
I was wondering if you sort of "Know" or have heard when the ZS/ZR will get their "Xenion" face lift?
Cheers
Mega.
Mega

This thread was discussed between 21/03/2002 and 23/03/2002

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