Wheels and Tyre sizes help please

[SMITHEREEN]

I know this has been asked a thousand times and I've seen the really helpful chart which has wheel and tyre sizes on it. However my questions are:

1. I currently have standard hubs which are auto. I'm led to believe there is a problem if I need towing with these on? so should I change them to lockers if so how many do I need any advice on good quality ones or stuff from the Bay ok??

2. In terms of wheels and tyres I currently have stock wheels (rusted will need refurb) with 205/70/R15 on. I was originally thinking I'd go for 225/75/R15 with no lift and everything standard. But then I clocked the attached pic and this is the look I'd like to achieve I'm thinking these are 235's on a 15 x 7" wheel am I right? if so what lift do you think this is I realise the bumper is different to stop rubbing issues any spacers?

[Larry]

I have just fitted a set of these exact tyres to my 15x 7 rims.

I'm not certain of the spec of my suspension but I'm fairly sure I have extended shackles on the rear only, the front looks standard.

These appear to fit really well, but I haven't driven it in anger off road yet, so I may find I get some rubbing.

[Larry]

See attached 235 75 15 on 15 X 7 wheels

[Larry]

Also worth mentioning that the 15x7 rims I have fitted have more offset than some but it's only marginally more, nothing silly. Not sure if this will make a difference. I can measure the offset if it's of any help.

[SMITHEREEN]

Thanks for the feedback Larry, they look spot on. If you could let me know what the wheels are or where you got them and measure offset that would be great. Are you running a standard 1.3 or 1.6 and would I have any issue with these using a standard 1.3 Samurai engine and transfer box?

Thanks again

[Jordi]

235/75s on a 15x7 can be fit with minimal modifications.

There is a seam / lip runs down the bulk head that needs adjusting (bending flat with a hammer).

If its a standard bumper fitted then it may need trimming slightly.

A standard 1.3 motor with original SJ / Samurai gearing is fine for 235s. If you wanted the gearing a bit closer to standard you could fit a 410 transfer box.

[Larry]

I'm afraid I can only really answer one of those questions properly - the offset! I'll measure that for you. I bought the truck with the wheels on so not sure where they are from.

My Sami has been off the road for over a year. In that time I've taken out the very tired 1.3 and just finished installing a 1.6 with a SU carb. Since that and fitting the new tyres a few days ago, I've only driver up and down the lane behind my house as it's not insured yet. So I can't comment on how well the 1.6 pulls at speed just yet.

I can tell you that the old tires were only half an inch smaller in diameter and it felt over geared and under powered with the 1.3, not really ideal. I'm not sure how my 1.3 compared to a healthy one as I've never driven any other SJ on road.

I'm expecting the 1.6 to be better but I'm also considering going for a rocklobster transfer box in the future, as that will improve the low ratio loads and also reduce high ratio by I think 12%, which should correct for the tyres (give or take).

[SMITHEREEN]

Really appreciate the info guys it's really helpful. Larry are you saying you think the 1.3 would be over geared and underpowered with the 235's on? Just interested to get your take as Jordi seems to think fine?

[Larry]

Sorry, no I don't mean to sound as though it's not possible. I think it will be driveable with the 1.3 and 235's. I just think that its already an underpowered engine by modern standards and every little helps to keep the power / gearing ratio right.

It will depend what type of driving you do too. It only really bothered me on motorways where 5th was sometimes too high and the engine didn't have the torque to hold speed on gentle inclines. I would have to drop into 4th and scream it's nuts off to get up a gradual incline, then back into 5th and foot to the floor just to maintain 55ish mph. Pottering around on local B roads it was fine!

I expect it will be ok and especially so if you are open to upgrading the engine or modifying the gearing in the future.

[SMITHEREEN]

Thanks Larry understood.
Anyone know anything about the hubs re. auto v's locking and do I need them for towing and if so are they needed on all four hubs or just fronts?