245/45/19 to 255/50/19

[JamesDon]

Hi all
I've just upgraded the budget tyres that came with my van. They were 245/45/19 on a 19x8.5 wheel.
I've gone for the Uniroyal Rainsport 5 which seem a great tyre but I've upped the size to 255/50/19. The van is sitting semi low on coilovers and it doesn't seem to rub anywhere yet. I've got more width, alloy protection and comfort. Another plus is the fact that they were nearly £40 cheaper per tyre!
Now obviously I've increased the rolling radius which means that when my Speedo says im doing 57, I'm doing 60.
This seems the only downside which I can probably live with and be cautious but I just wondered if there is any way of solving this with some kind of recalibration?

Also are there any other issues that I may not have considered?

Thank you
James

 

[Long tall John]

I think I’ve read somewhere that you can re-calibrate for an increased size but you cannot then recalibrate for a smaller size if you change again. So be cautious.

I would also go for a drive using an online speedometer to see what the real difference is. Your original size might’ve been under-reading meaning you’re not so far out as you think

 

[JamesDon]

I think I’ve read somewhere that you can re-calibrate for an increased size but you cannot then recalibrate for a smaller size if you change again. So be cautious.

I would also go for a drive using an online speedometer to see what the real difference is. Your original size might’ve been under-reading meaning you’re not so far out as you think

Hi John
Thanks for the reply.
I'm using the Google Maps navigation speedometer on my phone to get the accurate reading on the new tyres.
I did the same before (on the correct sized tyres) and the van speedo was pretty much identical.
I suppose I can just learn to always remember that I have no tolerance and should always be a few mph under speed limits.

 

[JamesDon]

Could I also ask what PSI's people would recommend for this size of tyre on a T32 which doesn't actually carry any real weight other then a pop top and rock and roll bed.

 

[sparkzer]

This is something that can be adjusted using VCDS, mine was also miss-reading and its now bang on.

There is a guide here however you would need someone with the cable/software to do this assuming you don't have it yourself.

 

[JamesDon]

This is something that can be adjusted using VCDS, mine was also miss-reading and its now bang on.

There is a guide here however you would need someone with the cable/software to do this assuming you don't have it yourself.

Excellent news, thank you very much for that. Is there a list of people on here that have VCDS in certain areas?

 

[sparkzer]

There was a map, but I believe a recent update broke it! lots of people 'added' themselves in this thread though - VCDS users

 

[Bav]

Excellent news, thank you very much for that. Is there a list of people on here that have VCDS in certain areas?

Try here (believe the yellow markers denote VCDS users).

 

[JamesDon]

Try here (believe the yellow markers denote VCDS users).

Thank you Bav
I'll have a look and speak very nicely to one of them. Hopefully someone can assist

 

[Lightrofit]

You don't mention if yours is a T6 or T6.1 but both can be adjusted. Just be cautious as whilst the T6 can be adjusted without issue, the T6.1 can be troublesome if coded incorrectly.

 

[JamesDon]

You don't mention if yours is a T6 or T6.1 but both can be adjusted. Just be cautious as whilst the T6 can be adjusted without issue, the T6.1 can be troublesome if coded incorrectly.

Hi, mines a T6 luckily.
I now feel like I should have stuck with the recommended size instead of trying to be smart but if it can be adjusted then I should be ok!

 

[Lightrofit]

Hi, mines a T6 luckily.
I now feel like I should have stuck with the recommended size instead of trying to be smart but if it can be adjusted then I should be ok!

It can be adjusted without issue on a T6 but only within set circumferences

 

[T6 Syd]

I can confirm that it is easy enough on a T6, I used OBD11 (Pro subscription though so that longcoding is available). I got mine spot on for 275/40/20, but due to rubbing I have changed wheels/tyres and adjusted the K setting back no problem. The guide linked in a post above gives an idea of the K value/circumference relationship. Willtheyfit or similar tyresize calculators will give you the % difference from OEM size or your old tyre size.

 

[sparkzer]

Hi, mines a T6 luckily.
I now feel like I should have stuck with the recommended size instead of trying to be smart but if it can be adjusted then I should be ok!

I don't think your original wheel/tyre size are a standard VW size so it was probably wrong before you changed the tyre sizes anyway so nothing lost there, now you just have the opportunity to put it right.

 

[KennyW]

Would love a set of Porsche wheels and considering a set from the Panamera, size: front 9.5jx20 ET65, Rear 11.5Jx20. Easy enough to source adapters to compensate for PCD. Anyone on here managed a successful install with these sizes?

 

[dubber36]

My main concern before size would be to check the load rating of the wheels. You may not intend to carry loads, but if the wheels are under rated for the maximum axle weight of your vehicle, you might run into problems.

 

[Pewt]

The rear arch is big but can't see any way a 11.5j will fit..................4x front wheels could work with the right size adaptors.

 

[KennyW]

Would love a set of Porsche wheels and considering a set from the Panamera, size: front 9.5jx20 ET65, Rear 11.5Jx20. Anyone on here managed a successful install with these sizes?

View attachment 183036

The rear arch is big but can't see any way a 11.5j will fit..................4x front wheels could work with the right size adaptors.

Was thinking something similar, I just really like the staggered look so would rather aim for that if it's possible. A the moment I have 8.5's on the front & 10's on the rear, but suspect in this case you will most likely be right. The 11.5's would need to run a 295 or 305 tyre.