Bigger tyres

[jumbodrw]

Hi Guys,

Thank for the add, as you can see i'm new on here..

Right my very first question!!

I've fitted rather large tyres to my van(i'm always in quarries etc need extra height) my van is a 2008 twin wheel 350 jumbo, the tyres I've fitted are 7.50R x 16 that measure 2530 mm rolling circumference or 784mm diameter.
Now when i look in IDS the biggest tyres listed are 2205mm is there anyway to put in my own measurements on this ?
Not too much of a problem as the speedo is only reading about 10% slow
Or can i put a sensor in the gearbox as i have wiring and alter IDS to get it to read this, Then alter the diff Ratio to get my speedo back.

Now i know this isn't a common mod but any help would be appreciated.

Neil

[knobby1]

Hi Guys,

Thank for the add, as you can see i'm new on here..

Right my very first question!!

I've fitted rather large tyres to my van(i'm always in quarries etc need extra height) my van is a 2008 twin wheel 350 jumbo, the tyres I've fitted are 7.50R x 16 that measure 2530 mm rolling circumference or 784mm diameter.
Now when i look in IDS the biggest tyres listed are 2205mm is there anyway to put in my own measurements on this ?
Not too much of a problem as the speedo is only reading about 10% slow
Or can i put a sensor in the gearbox as i have wiring and alter IDS to get it to read this, Then alter the diff Ratio to get my speedo back.

Now i know this isn't a common mod but any help would be appreciated.

Neil

Mk7's dont use the gearbox for the speedo, they use the ABS rings on the wheels via one of the modules. IDS only has a few options for wheel sizes....don't think you can put in a custom size.

Lord Knobrot

[jumbodrw]

Thanks for your reply,

When i was under the van yesterday i saw i had wiring down to the speed sensor hole is this same on all mk7 rwd's, i was just wondering if there was a setting maybe on engineering ids that would allow me to use this sensor for speed.

I must let you know that i haven't used ids much so i'm still getting round to all it's functions.
if i try to alter the tyre size or circumference i just get ABS lights on
But there is a setting that says
Customers own size in tyre size
So this had me thinking .
But if i select this there is nowhere to put and size into the box.

Neil

[Airthies]

Not sure on the IDS questions but more importantly do they clear all the metalwork and washer bottle properly?
I've got 225/75R16C on landrover weller 8spokes and they are a bit neat in the front (but more from the exaggerated offset)
You can get spacers made up for the front strut crowns to lift the front end and bung a spacer block between rear axle and spring to lift the body up a bit more.
Being RWD you can put a fair sized spacer on the front without worrying about drive shaft angles and spacing the subframe too. There's a guy down south profiles out plates to make strut spacers or you can order them complete from him.

Ps I'm permanently in and put of quarries and looking at doing more to my van for the same reasons, already lifted front 1.5inch and looking to lift more.

Sent from my anu5 using crapatalk

[jumbodrw]

Hi,

The rears fit no problems, just that the wheel is slightly forward in the arch and now you can notice it so i'm making up some spacers to allow me to move the axle back 10-15mm the OCD is kicking in

On the fronts, i had to trim the mudflaps just a little to stop rubbing and i've had to limit the steering rack by 3mm either side to stop the tyres catching on the chassis on full lock fully compressed suspension,
But other than that no problems, i just need a side step to get in the back now.

I'm going to raise the rear suspension about 50-75mm and just on sorting the front out,I think the sensible max will be 40-50mm on the front.

Neil

[knobby1]

Thanks for your reply,
When i was under the van yesterday i saw i had wiring down to the speed sensor hole is this same on all mk7 rwd's, i was just wondering if there was a setting maybe on engineering ids that would allow me to use this sensor for speed.

I must let you know that i haven't used ids much so i'm still getting round to all it's functions.
if i try to alter the tyre size or circumference i just get ABS lights on
But there is a setting that says
Customers own size in tyre size
So this had me thinking .
But if i select this there is nowhere to put and size into the box.

Neil

Might be the reverse light switch you're looking at on the box...they don't have a speed sensor. With IDS and wheel sizes, experiment with it, see what happens.....the older versions like the one I have may be different to the later ones.

Lord Knobrot

[jumbodrw]

Hi Knobby,

The minute i alter either wheel size in that setting or tyre circumference or both together the abs esp lights up,
I have a plastic plug in the gearbox where the sensor would be and i have wiring to it and just wondered if there is a setting im missing to turn this on, if not why the wiring?

it might just be a left over from the mk6 but seems a bit strange to me,

if anyone has ever messed with this please let me know.

as i said to start with i know this sort of modification isn't normal (neither am i)

but just trying to cover all base's the gearbox if off at the moment as i'm changing my clutch and flywheel, but that's a different story

Neil

[ned]

Hey Neil (good name that ) have you got a picture of these big wheels you have fitted, I'm running Weller's like Sir Airthies but I run 225 70R 15 tyres. N

[jumbodrw]

Hi Ned,


This is the rear

i will get the front when i get it back on its wheels after the clutch change,

Neil

[jumbodrw]

A bit close eh?

[ned]

Bloody ell there big what size are them in normal terms 205 80 or something, thought mine filled the arches. N

[jumbodrw]

Hi Ned,
7.50x r16
The closest metric tyre is 235/85 r16 but they are wider the actual metric size is 195/105 r 16

but with it being a twin wheel the front hubs etc are different so i dont know if the offset overall is different.

i've got 5 245/75 16 bf goodrich's if you want to try them had them on a sprinter i had before the transit only done about 10k still really good didn't catch on the sprinter on standard rims and they have 235/65 16's as standard

neil

[ned]

I would take you up on the offer if my wheels wasn't 15" rims Mr Airthies has 16"

These fill the arches enough with the pot holed roads N

IMG_20180627_164106.jpg

[knobby1]

What gearbox do you have?? .....And does it have ABS..?? Where is this switch...is it top left rear of box..??

Lord Knobrot

[Airthies]

Hi Ned,


This is the rear

i will get the front when i get it back on its wheels after the clutch change,

Neil

Rather than trying to shift the axle would it be worth just trimming a bit off the front of the arch and sill?

Would of thought the hub and wheel offset for the dualies would bring the tyres back to the same track width as std singles on the front? But open to correction on that one.

I've only gone up 15mm in diameter and I've noticed that, you've got another 40mm on mine I'm surprised your not collecting any metalwork other than inner chassis legs?

This is the front of mine now.

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