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Jimbo
03-03-2005, 11:20 PM
I've never owned anything other than front engined front wheel drive cars before my current venture into the world of VR4s, and because of this I have an interesting question to field to the forum.

Since getting a puncture I've temporaily put an older tyre on the back until I get replacement(s), and the thought process was to get 2 new tyres for the back wheels and keep the other good tyre as a spare.

The current set of tyres have only about 3000-3500 miles on them, so this seems the logical course of action to me, but does anybody have any other views on this?

Would you put the new tyres on the front and the older ones on the back (or vice versa)? What sort of wear differential would make a handling impact on a 4WD car like the VR4? Would anybody advise getting 4 new tyres to offset any potential for unbalanced handling?

adam_shaw
03-03-2005, 11:24 PM
With 2WD I always replaced in pairs (or else altogether) so when I got a puncture on one of my slightly $hagged Pirelli I went for all 4.

I guess, if you only have a few K on them the difference in circumference wouldn't be at all noticeable.

Worn (say half way) and new would be bad news I should think?

I stand ready to be ridiculed....

A

ps. I get a company allowance for all car related expenses, therefore am immune from considering the financial implications of binning 3 perfectly legal tyres

KiwiTT
04-03-2005, 12:11 AM
I always change all 4 tyres even on front drive cars. I also rotate them frequently (every service) to get an even wear pattern. Also I recommend putting on the same brand and model in all 4 corners.

Also make sure if you select directional - like our favorite (http://www.clubvr4.com/forum/showthread.php?t=5709&highlight=Eagle) it will be important that they are in the right direction

Kenneth
04-03-2005, 12:14 AM
With AWD it is recomended that you replace all 4 at the same time.

Personally I wouldn't unless the tyres were just about shagged anyway or I was changing to a different tyre.

In the case of the VR-4 I would be inclined to put the new tyres on the back as the torque split goes 40/60 front/rear under acceleration. last thing you want is the back comming around to meet you when hauling out of a corner (especially in the wet) I found this out with my Galant 1.8 GDI (AWD) which went arse around front very rappidly... had new directionals on the front and old uni-directionals on the back.

SGHOM
04-03-2005, 12:17 AM
I would replace the front tyres Jim. even though the VR4 has a 50/50 4WD split [ unlike the skyline which is RWD untill called into action ! ] purely on the assumption that they will be the ones scrambling for most grip at the ring !! :rolleyes4

SGHOM
04-03-2005, 12:22 AM
In the case of the VR-4 I would be inclined to put the new tyres on the back .
there's your answer then ?? :rolleyes4 :rolleyes4 [ front I say !! :embarasse ]
IMHO, in a race situation, I'd want my fronts to grip like hell to haul me around the corner !!! who cares if the back end loses traction !! ....... more fun. :thumbsup: :drummer:

Kenneth
04-03-2005, 12:51 AM
there's your answer then ?? :rolleyes4 :rolleyes4 [ front I say !! :embarasse ]
IMHO, in a race situation, I'd want my fronts to grip like hell to haul me around the corner !!! who cares if the back end loses traction !! ....... more fun. :thumbsup: :drummer:

All depends on what you want to do I guess. My recomendation was based on the fact that with the 40/60 torque split under acceleration, your rears are going to get a pounding.

Also, it may be fun to slide the back out, but its not how to drive fast.

SGHOM
04-03-2005, 01:06 AM
My recomendation was based on the fact that with the 40/60 torque split under acceleration, your rears are going to get a pounding.

.
I agree. but I'd rather loose traction on the rear than the front. oversteer is fun, if your skilled enough to control it. :embarasse understeer can be a little more scary !! :rolleyes4 .... armco here I come !! /help

Roadrunner
04-03-2005, 01:26 AM
With the centre diff, there should not be more than 4mm difference between treads on the front and the rear, otherwise the diff is constantly working overtime to equalise the rotation. I'd always replace tyres in pairs at least so there's no wind-up in either the front or rear diff - this is especially important with the rear diff on the VR-4 as it's working harder with the AYC clutches and the limited slip. My preference is always to replace all 4 at once and I do rotate (once) during the life of the tyres - swapping front to back - to equalise the wear. If only replacing one pair, I'd always put the new ones on the front - the rear can do what it likes, but I like the front to be pointing in the right direction ;)

Edited to add: Oh, and I always fit the same tyres on all wheels. Regardless of whether tyres have the same load rating / speed rating / width / profile, etc., different tread patterns will have different behaviours (however slight) and probably different compounds which must affect the handling and grip. I recall, shown not too long ago on this BBS, a picture of a smashed Evo which had different tyres between front and back. Not saying it was the reason for the crash, just that it may have been a causal factor ...

Kenneth
04-03-2005, 03:36 AM
Could argue relative driving preferences forever I guess :rolleyes4

Sounds like most ppl would put them on the front... Fair enough, I would be very tempted to also.


To digress slightly...

The way my car is set up (suspension mainly) I get neutral handling. So basically the whole car drifts instead of the front pushing or the back comming out.

This doesn't quite hold true for lower speed sharper turns, which dont matter much anyway...

Neutral handling means that If I go too hot into a corner and it doesn't look like I'm going to make it (hello armco), I can back off a fraction and tighten up my line, if I get the line and speed right in the first place, the hammer is down and the car drifts under full throttle and tracks-out to the edge of the road.

First time I did that, I just about soiled my pants... Thought I was going to drift off the road. Damn it was fast though.

When I get better tyres, ill have to go test that rd again.

Jimbo
04-03-2005, 03:32 PM
Thanks for the comments everyone, that made interesting reading. :thumbsup:

I think I'll go for two new GS-D3s, get them fitted up front, and swap the older ones to the back. When I can afford it (they're £120 a tyre - UNFITTED!) I'll get a couple more and just be one tyre away from a (dry) track day set /yes

KiwiTT
04-03-2005, 08:46 PM
...they're £120 a tyre - UNFITTED!

We get ours from Germany @ NZ$199 (about £80) for 225/45 R17

Jimbo
05-03-2005, 02:28 PM
What do they charge for 235-40-18's?

I must admit I've scoured the web long and hard many a time, and £118.20 from MyTyres is way, way cheaper than anywhere else I've seen to date.

KiwiTT
05-03-2005, 09:02 PM
If you are getting 18" that is a good price.