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31.7"

Posted: 13 Nov 2009, 22:37
by ericos_bob
Who is running 235/85/16 tires on their syncro's and what experience have you had with clearance front and rear. Do these fit a standard 16" syncro or do they also require further modification to avoid tire scrub on full lock. Am especially interested in how these tires effect your steering. Reason tires this size interest me is that apart from having my gearbox rebuilt for a taller 4th I'll need to fit tires this size If I am to keep my gearing tall enough to be able to cruise without excessive over rev.would be great to hear some opinions.cheers

Re: 31.7"

Posted: 13 Nov 2009, 23:03
by ..lee..
i`m running 29`s on my 16" but i have longer diffs in, 4.8cwp with standard box ratio. i`m doing nearly 75 at 3500rpm.

have you seen this http://www.syncro.ca/tiresize/" onclick="window.open(this.href);return false;

lee.

Re: 31.7"

Posted: 14 Nov 2009, 10:12
by Aidan
235/70/16 are i believe sensible max, 245/75/16 I think is what Russel runs

85be same as ratios like 215R15s too big for a 14" without mods required

Re: 31.7"

Posted: 14 Nov 2009, 10:53
by ericos_bob
Thanks lee and aidan. I used the tire/gearing calculator and would be doing 63 at 3500rpm. With stock tires and 5.43 gearing it's around 61 at 3500 so at least would end up slightly taller than stock and I found even the stock gearing could be taller and that's running the 2.1 vanagon engine. Certainly can't go smaller than 235/85/16 without having a taller 4th . Would be quite low gearing still with a 2.2 subaru engine in. Have watched this clip of a 16" with 235/85/16. It seems to make an odd sound though like shocks topping out if you listen to the clip.? http://www.youtube.com/watch?v=lf_JiYYDWOE" onclick="window.open(this.href);return false;

Re: 31.7"

Posted: 14 Nov 2009, 11:26
by syncropaddy
Will you have the torque to pull these big tyres and tall 4th?

Re: 31.7"

Posted: 14 Nov 2009, 13:18
by Russel
I have 245 75 16 on my precent van and have had 235 85 16 on 2 of my vans but with extensive upgrading and modifying chassi and arches.
It is a lot of work.
245 75 16 also need work to make fit but a little less than the bigger.
Russel

Re: 31.7"

Posted: 15 Nov 2009, 02:51
by ericos_bob
Hey russel,

Thanks for your input. Would you mind explaining what kind of modification a 16" syncro requires to fit this size of tire.The two you have running 245/85/16 are they modified 14" syncro's? As expected there seems to be a mix of information in regards to this issue and such is a problem when trying to find answers on the internet. I read this article http://www.fastforward.ca/syncro/tech/TireFitment.htm" onclick="window.open(this.href);return false; and it seems a 16" syncro only requires minor modification to the rear trailing arms in order to accomodate 235/85/16 tires though have noticed there was no mention of potential tire scrub under heavy spring compression or at full steering lock.

Paddy, I only intend to install a taller 4th should I not be able to shoehorn 235/85/16 tires on my syncro. With these tires my gearing is still lower than most syncro's that have modest tire upgrades with 5.43 cwp so I only require extra power to counter the weight of the larger tires and the 2.2 subaru engine will pull this easily still giving extra bottom-end torque over a stock 2.1 engine/wheel set up for offroading.


Lee, yes it is an excel version of this gearing calculator that has brought me to this combination. A very nifty little program indeed,cheers

Re: 31.7"

Posted: 15 Nov 2009, 08:38
by Russel
245 75 16 will need at least a 2 inch lift + wheel arches stretched and modification to front out rigger.
235 85 16 will need 16 arches removed(cant reinstall because they are to small) custom arches then made. You will need seikle springs even with these at full compression on front the wheel will rub top of front arches.Front arches need to be made longer front and back and out riggers need total modifications(you have to loose the jacking point(this applies to bothe tire sizes when done proply) You will also need trailing arm mods.
Brakes will also need uprating.
This is a long and extensive jod and applyes to a 16 syncro cant be done to a 14 unless using 16 parts.
Russel

Re: 31.7"

Posted: 15 Nov 2009, 10:04
by syncropaddy
Time to change your final drive .............

Re: 31.7"

Posted: 16 Nov 2009, 10:44
by ericos_bob
Russel, awesome information I am bummed there is so much work to do fitting the 235/85/16 tires but stoked that a 245/75/16 can be done with less work. That is still a mite taller than stock and a beefy tire like that could be of benefit for the sand? Thanks for the gearbox and diff you guys sent to me in australia too I can't wait to get my syncro on the the road to go off the road. The white syncro-nutz shirts are a good fit too. Are a hit on the golf course :lol:

Paddy, why'd you have to talk me into going the 245/75/16 route. I would have much rather just changed my final drive. Oh well :mrgreen:

Re: 31.7"

Posted: 16 Nov 2009, 15:35
by syncropaddy
My Multivan arrived with a 5.83:1 final drive which at 4000 rpm allowed a massive and noisy 112 kms flat out with the 205/14 tyres it came with. I changed the FD to 4.86:1 and fitted 225/70/15 and can now cruise at 100 Kms at 3100 rpm all day long and on to 130 kms at 3800. Wont go any quicker with the 1.6TD in her :(

Re: 31.7"

Posted: 16 Nov 2009, 21:05
by ericos_bob
Sure it would be nice to go that tall and I probably would do so under the right circumstances. I actually do have a spare gearbox in perfect running order plus the front diff with a 5.43 r&p out in the shed but that's going to sit there until I need to overhaul this gearbox. When the extra money comes in a 0.70 4th will do the trick.. . In the meantime I'll have to put up with the higher revs. I usually cruise at around 55mph on the highway. This is a habit that develops from owning a bay window kombi for too long.

Re: 31.7"

Posted: 20 Nov 2009, 00:25
by Syncro G
235's are pritty heavy too (the Mitchilens on my landy are about 35kg on standard LR 5.5F rims, which I think weighed about 13kg. Upping the diffs might give the same overall gear ratio but you'll probubly find the 235's take a lot longer to get up to speed - they certainly stretch the performance of my 60bhp N/A diesel to the limit . Very noticable when compaired to the 7.50R16 I had on before, which are a simular rolling size.

Re: 31.7"

Posted: 20 Nov 2009, 12:40
by syncropaddy
Good point that Glen. We tend to forget that big wheels carry extra weight and I imagine 235/85/16 wheels and tyres are, as you say about 45 - 50 Kgs each. What you have then is 4 flywheels that need to be braked and as we all know, the standard brakes are adequate, but poor by todays standards so the bigger wheels would add to braking distances / fade etc

Re: 31.7"

Posted: 20 Nov 2009, 13:05
by syncrodoug
Russel, what width rims do you use with your 235/85x16?
Doug