Thinking about putting bigger tyres on the rear of my car so it puts the power down better.
Currently running 215 40 17's on Comp MO's which I think are an 8J rim.
No idea what the offset is to be honest.
Question is, who is running bigger rear tyres on their cars and does it have any negative effect on the handling and or even the aesthetics.
I know a lot of modern performance stuff have larger rear boots (BM'S/911's etc).
Was considering 235's 40's or even 245 35's as the latter has a closer circumference.
Be interesting to get the experts opinions

 

Changing the rear beam might be a better way forward

 

I was going to say the same, 6 degree beam.

 

They are Revolution Millenium wheels Ed, 8j offset I think is et30, check it is stamped on the wheel itself.The paperwork for the wheels will be in the invoice file Ed.

CheeRS.Lee.

 

What diff have you got fitted mate?

 

Think its a standard diff but has shims fitted to minimise the negative camber?
Obviously still learning about these cars lads so bear with me.
Not sure what you mean by changing the beam??
I was also thinking about the aesthetics as the 215's are like push bike tyres by todays standards, so basically grip and the looks

 

Ed, he means change the complete rear beam for an adjustable replacement(about 1k to 1.2k) if you upgrade the diff to a gripper or Supra diff that will help a lot with the grip to Ed.
Yes standard diff on the car Ed at present.
CheeRS.Lee.

 

Really like the gripper diff gives great traction, is quite noisey but doesn't bother me adds to the experience of the car

 

To be honest an LSD would be a bit extreme and big money. I'll just put some bigger shoes on for now maybe some 225's/235's or 245's the latter will probably catch. Lee the arches have been rolled haven't they?

 

Fair play mate if you can get away with wider tyres why not, be careful though as the planet gears on the standard diff aren't the strongest.

 

Well 235 35 17's are like rocking horse sh*t can't find them anywhere.
Do you reckon 245 35 17's with the ET30 8J rims will fit or catch the kit?

 

The tyres that are on the wheels at the moment dont look like the right width for the wheels? To me they look like they have been stretched onto rims which could take a wider tyre. I did think this when I looked at the photos you recently put up.
Maybe try some wider tyres on the current wheels and see how they perform?

 

Yes they are a bit stretched mate. They 215 40's 17" rim 8j

 

I have the same size tyres on my 17x7 Oz Cronos on my Saff so yours are definitely to narrow for your 8

inch wheels.
215/40/17s sit right on my 7 inch wide wheels.

 

Have to agree with that mate tyre is a lot more flush with the rim, also less chance of the dreaded kerb rash, gonna try some 245's on the rear when i'm due some new. Cannot get a suitable 235 in a 17" rim anymore

 

Yes Ed the arches have been rolled front and rears. Go for 235/40/17 if you can't get a 235/35 size, see how you get on with that.

CheeRS.Lee.

 

Cheers Lee

 

Forgot to mention Lee are they adjustable Koni's on the car or has it just got lowered springs in place?

 

You can get Federal 595 RSR track day tyres in 235/40/17 sizes for Ł84.50 each from mytyres.co.uk. Same as what I have got on my Saff but in 215/40/17s. Good tyres with plenty of grip.

 

Thanks for the heads up mate

 

I also have 215/40 r17 tyres on 8J wheels and they are a bit stretched, but not really a problem. The ideal wheel for a 215 tyre is actually 7.5J, so 7J is a bit small. 8J would be ideal for 225, but I don't think 225/40 R17 or 225/35 R17 exist.

 

225/35 17 exist, yokohama and kuhmo makes them. But the tire height isn't that ideal. you feel every small bump and inperfection in the road.


got 225/35 17 on 7.5j

 

Its the 235/35 17 I was looking for. This doesn't exist or I can't find any. So will no doubt go 235/40 17

 

You could try some 225/45's on the rear?

I like the rear sitting slightly higher than the fronts.

Get some decent trackday tyres and they will grip so much better

Cheers Paul

 

Carbon 1993. I had kuhmo Ecsta tyres on my Saff and I found them quite a hard compound and now have the Federal 595 RSR tyres which seem a bit softer and dont give such a harsh ride.

 

yes the rears are Konis and are adjustable with Ahmed Bayjoo springs.

Thanks. Lee.

 

Hi,

I had 245/35/17 toyos on comps 17/8J Et33 on the rears and they fitted without scuffing. Very close though (1mm odd on squat) These tyres will keep the rolling radius the same as the fronts keeping the 215/40/17 tyres. (Not that you need to on a 2wd)
But with an et of 33 I recon you will have to take a couple of millimetres from the rear arches or machine the face of the wheel. Also be advised that different tyres of the same sizing have different overall widths/shoulder heights.


Hope this helps.


Tim

 

Cheers Tim
I have an offset of ET30 and the arches have been rolled, albeit the body kit is still the same, do you think it will be ok?

 

I think you would still need to take 3mm off the wheel face bringing your offset to 33 to clear but you could try it first. But please look at the overall tire width of tyres in that size as they do differ from manufacturer to manufacturer.
Go on toyo tyres uk and look at sizing dimensions for a 245/35/17 T1R you do not want anything wider than this. I will attach a picture of them on mine.

Cheers.


Tim

 

Cheers Tim, appreciate your help mate

 

I have Toyo T1R's on the front and they are ok, but when put on the back with 500hp they are useless for traction compared to a track day tyre

Cheers Paul

 

Purchased some 245 35 17's not got round to putting them on yet.
Just have to see how I go with them. I know there are some 6mm shims on the rears so that will give me a bit more if I remove them. Car is just awful traction wise on the rear at the moment with the 215's. To be honest as soon as it boosts even in 3rd gear it just looses traction which makes it difficult to relax in it to be perfectly honest.

 

As Turbotrev said you will notice a big difference in traction with track day tyres fitted. My 2wd Saff is only 450 Bhp but when I first got the extra power it was on Goodyear Eagle F1 tyres 205/40/17s which were no use at all in stopping wheelspin. it was quite scary and like driving on ice so that was why It now runs on the 215/40/17 Federal 595 RSR track day tyres. Much better grip now and although you can still do dry road powerslides its not as unpredictable as it was on the F1s.

 

AS said, track day tyres are much better re grip. On my standard i5 inch cosworth wheels I have Toyo 888 215/50/15 on the rears which are actually 228mm wide. These Tyres I found to be very good when warmed up.
I now run Team Dynamics Imola wheels 7.5/17 inch with Yokohama Ad08r 215/40/17 tyres and these I cannot rate enough more grip than the 888's at colder temps and not a lot in it when warm.
Being a 7.5 rim the 215/40/17 Yokohama's (which are actually 218mm wide) fit the rim pefectly as they also have high shoulders.
8 inch rims are to wide for our cars as you have to start chopping aches etc if you want a tyres that can protect the rim.


Best.

Happy Xmas.

Tim

 

Did you get a chance to try the tyres on ?


I was going for 235/40/17 on 8x17 Millenniums - didn't know 245/35/17 were an option.


Interested to know how you get on for clearance

 

Have you read the thread "Meaty Tires" by Supra92? Ridgey has very wide wheels and tyres on his Saff and they fit ,but only just! Read what he has said before you get carried away thinking it is straight forward.

 

Yes mate,


Just curious as to whether 245's would squeeze on.


Do 3 doors have better rear tyre clearance than a Saph or 5 door ?

 

I am sure someone will be able to tell you that but I think once you start going as wide as 245s there could be clearance issues. The op with his nice 3 door who asked about the wider tyres would notice a big difference in grip just by fitting track day tyres with a 215 width.They make a big difference from normal road tyres and I am sure it would sort out his lack of grip problems.

 

Hi Mark no mate not fitted them yet.
I will let you know hopefully they'll be ok.
Its not just to improve grip I also think they will improve the overall aesthetics. 215's look like bike tyres these days.

 

Crimp. Are the wide tyres track day ones? If you are running big power with 2wd I would advise that it is worth it.