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-   -   4x4 614 Conversion (https://www.horizonsunlimited.com/hubb/heavy-overland-vehicle-tech/4x4-614-conversion-81912)

cedar 14 May 2015 18:52

4x4 614 Conversion
 
1 Attachment(s)
Hi all

This is my new baby, a Mercedes 614 4x4 ex Norwegian Police surveillance van. Built for the winter olympics in 1994. Presently full of swivel chairs, desks and monitor stations.

It,s only done 64k kms from new and probably serviced regardless, no rust to speak of, 2 full sets of wheels and tyres, 1 set studded.

It is pretty slow so I am looking for a set of 19.5" wheels.

My query is does the rim width vary much? I have seen 225/70 (Yokohama) 245/70(Bridgestone) 265/70(MichelinXDE2) 285/70 (Toyo)

I love XZY's, but could not afford a set of new ones, (if they do 19.5?) so the XDE is probably favourite, but what width rim do I need? They are 6 stud on 8' centres.

If anyone wants some as new 205/75R17.5 i've got 13!

moggy 1968 14 May 2015 23:47

don't forget, although your top speed will increase, your acceleration will drop off severely. The tyres you've listed vary hugely in width, which also means their height will vary enormously as the 70 in the size is the percentage depth of the tyre wall relative to the width. between your smallest (the 225s) and the largest (285) your increasing the diameter of the tyre by 84mm, which is a lot. you would also need to carry out some big mods I would think to fit a 285mm wide tyre on a vehicle designed for 205mm

If my maths is right, your increasing the tyre diameter by 142mm from standard if you go for the 285, and around 114mm with the xde. Thats a hell of a lot and will require some serious mods.

you will see a 13-16% change in speedo reading (under, 265 to 285 so watch out for those speed cameras!) which should be more or less replicated in an increase in road speed (not indicated obviously) but a dramatic drop off in acceleration

you would need an 8 inch wide rim for the xde, and some serious wheel arch flares if thats a twin rear axle!!

m37charlie 15 May 2015 01:54

Quote:

Originally Posted by moggy 1968 (Post 505084)
you would need an 8 inch wide rim for the xde, and some serious wheel arch flares if thats a twin rear axle!!


There is no such thing as a 19.5 x8 wheel
The 225 and 245 will will take a 6.00 or 6.750 rim
the 265 and 285 will go on a 7.500 rim.
There is a 19.5x8.25 rim for 305/70R19.5

Charlie

tacr2man 15 May 2015 07:16

Before you get too carried away with the idea that bigger tyres will fix your speed problem , these were never rocket ships! Is your speed limited because you are running out of revs, if not then fitting taller tyres wont help
and you will just have another problem , not being able to make normal use of the gearbox , and having to use lower gears climbing and slightly slower acceleration . What sort of cruise speed are you looking for?

moggy 1968 15 May 2015 16:46

Quote:

Originally Posted by m37charlie (Post 505091)
There is no such thing as a 19.5 x8 wheel
The 225 and 245 will will take a 6.00 or 6.750 rim
the 265 and 285 will go on a 7.500 rim.
There is a 19.5x8.25 rim for 305/70R19.5

Charlie

I have no idea (or interest!) in whats available, just saying what kind of size you need to fit the ops preferred width (265) on. After that it's upto to the OP to find out or others to say whats actually available, you would have to get the nearest equivalent. there is some degree of flexibilty in terms of what tyres will fit what rims. I'm currently running 235s on 8 inch rims, but they were apparently a bitch to fit! But that was what I happened to have left over in my garage and at £600 a set I wasn't about to buy a new set! Also I went for an 8inch rim, so I could get a -33 offset (not possible on 7inch rims) and not lose too much on the steering lock, knowing there was room in the wheelarches (just!). You can get any wheel you like made (assuming it's physically possible), at a cost. 19.5x6.5, 7.5, 8, 8.25 or 10, whatever you like!

My main points are:
a. I don't think this will work without a great deal of modification
b. It will have undesirable consequences you don't appear to have considered. If as tacrman has suggested, you aren't just running out of revs you may end up with an even lower top speed because the engine won't pull the gearing!
Then there is the acceleration I have already mentioned, you may find hill climbing a chore. then there is physically fitting the wheels, you need to consider steering lock, fouling on bodywork and suspension components etc and in with that as well as the size of the wheels you need to think about the offset, which you haven't mentioned. you may need a big -ve offset for the tyres you want to clear components on lock, which may require a custom wheel. After all that you need to think about the additional strain all this will put on other components such as steering, bearings, transmission etc. You may need a suspension lift, which will have an impact on steering geometry so steering may require modification. You may find you need to extend propshafts, anti-rollbars don't fit etc etc. Of course, all this can be overcome, but there are a multitude of things to consider before undertaking such a mod. I'm not saying it can't be done, just that it's not as simple as just chucking on a bigger set of wheels and tyres.

Your opening up a can of worms making such a big mod I reckon without some serious investigation first.

cedar 15 May 2015 18:55

Wheels
 
Thank you all for your thoughts, that's the sort of thing I need.

I am not running out of revs, it's just running at 2200 rpm at 50 and I would like to get this down to 1700, so it's still on boost. I don't particularly want wider tyres as this will increase rolling resistance.

As Moggy says, depth is a sum of the width, but maybe I should lower my sights a bit and go for 245

I have to get a new speedo anyway for the MOT as this is in Km, so I will get it re-calibrated. As you can see from the picture there is loads of room in the wheel arch, so I don't have to mess with the suspension (there is one in iceland with R20 unimog wheels)

Any more ideas welcome

Bruce.

moggy 1968 15 May 2015 21:40

it was after looking at the pics I thought you might struggle! At least some trimming on the bumpers and wheel arches, not forgetting it has to not foul on full articulation and full lock.

Jant 16 May 2015 10:12

Hello, I am new to this forum and am planning to do some overlanding next year.

I was wondering where you got the van from as I am looking for a Merc T2 4x4 to turn into an overland camper.

Cheers

cedar 16 May 2015 13:44

T2
 
Hi Jant

I have been looking for years, there was one for sale in France in very good condition, but too expensive for me, look in the for sale thread.

I had been looking for an 814, but widened my search to 815 and 614, and this was with a dealer in Norway

Jant 16 May 2015 16:47

Thanks for the reply, I saw the ad for the one in France, but as you say, it is expensive as it is already converted.

It is also from 1997 and I would prefer an earlier one, with less electronics :)

I hope all goes well with your merc :)

moggy 1968 16 May 2015 19:26

they are like rocking horse poo, and generally fetch a good price, because they are damn fine vans. The last decent van mercedes made!

James Rothwell 2 Jun 2015 07:55

Do you have any interior photos you can share, I'm curious to see.

cedar 17 Nov 2016 13:07

Speed!
 
1 Attachment(s)
Hi all

A cautionary tale, in my search for lower revs I invested in a set of 9.5 r 17.5 xzy's at some cost, the result being about 4 mph, they look great and will do the job, but I will have to change the gearing in the transfer box for any real difference, then the step between 3rd and 4th will be to great, just have to go slow.

Bruce


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