Jump to content
SAU Community

Recommended Posts

I have an Aussie r31 and purchased some cheap rims, ideally they would have been the right offset, but they were cheap.

I need to buy spacers.... so how do I increase my track evenly?

Was guessing 25mm for the front and 20mm for the rear. Hopefully, putting the wheels closer to the guards, increase track and let me use my wheels :)

The new wheels specs are:

16x7(?) wearing 205/55/16's

16x8 wearing 225/50/16's

Offset for the rear is +34, not sure of the front as the stickers are worn. Technically speaking the rear "fit" with no spacers. The fronts won't fit to my liking, a bit too close to hitting the strut.

The stock wheel specs are:

tyres.jpg

^^ linked to r31skylineclub.com ! (will change link if asked)

Will I need to try to find out the front offset before this question can be answered? If so how do I measure it?

Thank you :)

+34 offset for an 8" rim is perfect fit for r32/r33. But keep in mind, it's not goign to look fat on an r32/r33 guard. It isn't 'out enough'

However, it really depends on the particular car. I'm not sure of the stock offset of the r31 wheels. You really need to find this out first.

Hopefully the offset of the front wheels you've got will be matched to the rear ones in typical jap mismatched width style. Hopefully the offset of the fronts will be about + 30 or +28

I would not run spacers on your car especially if drifting. If the reason for the spacers is performance, it won't be noticeable. If it is for looks, sorry, but you're not trying to build a show car are you?

PS: offsets should normally be stamped ontot he back of the wheel. you'll ahve to look carefully because it mgiht be on a sticker or stamped, but it's probably covered in brake dust.

Can't you try the wheels on? or are they 5 stud and you havent' done the conversion yet?

There is also some geometry aspect to messing with the track width and all, there is some tech term that describes the projected line from the suspension pivot points(i think) that put an imaginary point on the ground where the centre of your wheel should be sitting, when you widen the track with spacers you throw this out. Cant remember what its called nor how bad or relevant it is to motorsport but it stuck in the back of my mind.

Hopefully SK or someother suspension guru can explain this point better or if it even exists...maybe im talking shit and getting confused with something else.

Edited by r33_racer
There is also some geometry aspect to messing with the track width and all, there is some tech term that describes the projected line from the suspension pivot points(i think) that put an imaginary point on the ground where the centre of your wheel should be sitting, when you widen the track with spacers you throw this out. Cant remember what its called nor how bad or relevant it is to motorsport but it stuck in the back of my mind.

This is EXACTLY what I would like to know. If I was keeping the stock tyres, it would be easy, I would just put the the same sized spacers all around... But with the addition of different sized wheels, not to mention the fact they're different sized front to back makes my brain hide thinking about it :P

There is also some geometry aspect to messing with the track width and all, there is some tech term that describes the projected line from the suspension pivot points(i think) that put an imaginary point on the ground where the centre of your wheel should be sitting, when you widen the track with spacers you throw this out. Cant remember what its called nor how bad or relevant it is to motorsport but it stuck in the back of my mind.

Hopefully SK or someother suspension guru can explain this point better or if it even exists...maybe im talking shit and getting confused with something else.

how would running a 20mm spacer be any different to the following scenario:

stock wheels are 8" +30 offset. If you run an 8" wheel with a +10 offset, isn't the net effect the same?

I believe that alignment issue is to do with std setup and probably std wheels and offsets. But i would say your logic behind the 20mm different offset is right, well it makes sense.

A spacer, i guess is effectively creating an artificial offset to help make the wrong rim fit right.

There is also some geometry aspect to messing with the track width and all, there is some tech term that describes the projected line from the suspension pivot points(i think) that put an imaginary point on the ground where the centre of your wheel should be sitting, when you widen the track with spacers you throw this out. Cant remember what its called nor how bad or relevant it is to motorsport but it stuck in the back of my mind.

Hopefully SK or someother suspension guru can explain this point better or if it even exists...maybe im talking shit and getting confused with something else.

You talking "scrub radius"?

Frankly, wheels that aren't designed to fit your application are bloody expensive, regardless of how much you didn't pay for them. Buy wheels designed for the purpose and you can't go wrong.

Thanks for your replies guys... I don't mean to sound unappreciative so I guess I'd better re-phrase my question:

What size spacers will I need to use in order to change the effective offset of the wheels while also widening my track and keeping the track alignment front to back even? :)

As it stands, because I don't know the offset of the front wheels, I am thinking of using 25mm spacers on the front and back - thereby keeping the same offset variation all around the car. The downside with this approach is assuming that the wheels I've purchased were actually correctly offset in relation to each other. I'm thinking the likelihood of this is high however if there is some advantage gained by moving the 7" (thinner) front wheels outward, increasing the front track in relation to the rear, then I would fit 30mm to the front and 25mm to the rear. Or perhaps 25mm to the front and 20mm to the rear.

That are my thoughts so far.. not sure if I'm on the right track (no pun intended) :happy:

Any on topic answers more than welcome !!

well if you want to conver a +30 to an effective +20 then you need 10mm spacer.

Hello ,

You must work out the offset of your front(new) rims you are wishing to install.

If the rears are +34mm and 8 inch. More than likely the front are +22mm at 7"(Or close too) this would have given the balance that the original suspension was set up to do.Do a quick measurement to see if this is true.

The previous owner of these rims worked it out and purchased the correct offsets.

By putting spacers as what was stated you are loading pressure on different points of the suspension

that were not designed to take.

Smaller front tyres allow you to steer better and larger back tyres allow you to put more power onto the ground, this is the logic. :ninja:

Thanks for the posts guys :laugh:

All very good points... ... none really answered what I was getting at :P anyone else see what I'm getting at?

Provided you get your offsets correct, as long as you use the same tyres on the front,and the same tyres at the back all is good. :):):):):):ninja:

DID I GET IT NOW?

your basically asking us to work out for you what sized spacers you required inorder to achieve an even offset all round so your track is not uneven from its std setting?

You have given us the rear offset, now we require the front rim offset which as stated before should be stamped on the back of the rim somewhere. Go find it out for us.

Based on what youve given us so far a 20mm spacer is required on the back, which is a common sized spacer to use.

Once you get the front then we can work out the required spacer needed to maintain the front offset so they clear and work for you.

From what you stated in the first post, thats what your asking. For a road car if the track is actually out of whack from stock its not really that big a deal, so long as its not way way out, which it wont be.

Edited by r33_racer
Provided you get your offsets correct, as long as you use the same tyres on the front,and the same tyres at the back all is good. :D:):):):):P

DID I GET IT NOW?

HEHE.. actually yes.

Except that the front and rear tyres and wheels are different :):D

I wouldn't ask if they were the same hehe I'd just whack on the spacers to maintain close to default offset.

your basically asking us to work out for you what sized spacers you required inorder to achieve an even offset all round so your track is not uneven from its std setting?

You have given us the rear offset, now we require the front rim offset which as stated before should be stamped on the back of the rim somewhere. Go find it out for us.

Based on what youve given us so far a 20mm spacer is required on the back, which is a common sized spacer to use.

Once you get the front then we can work out the required spacer needed to maintain the front offset so they clear and work for you.

From what you stated in the first post, thats what your asking. For a road car if the track is actually out of whack from stock its not really that big a deal, so long as its not way way out, which it wont be.

That's right - except I don't want to have the original offset, I'd like to increase track... evenly.

I don't actually need for you to work out the offset and spacer by adding the sum of the two in order to give me the actual offset of the wheel :) I just want to know that when I whack on a 25mm spacer on the front and 20mm on theback (for example) that the middle of the front tyre and the middle of the rear tyre are on the same vertical axis (assuming the steering wheel is straight and everything is aligned properly).

I should break out the paint diagrams hehe.. :)

  • 3 weeks later...
adding a 25mm spacer to a +34 wheel makes it effectively a +9 offset.

Thank you - I stand corrected :P

So if I have a rear 8" rim with +9 offset... what offset will I need on my 7" rim on the front so the middle of the front wheel is the same as the middle of the rear wheel?

I assume my highly technical diagram below will show what I'm getting it. This is all driven by the assumption that the picture on the left is ideal, that the middle of both wheels should be the same front to back. Maybe I could be wrong....

post-3612-1158558484.gif

When you are talking track, width is not applicable. Because offset is measured from the centre of the wheel, where track also happens to be measured from, then the offset directly relates to the track. So if you want it even with the rear wheels, then you will need a +9.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • I know why it happened and I’m embarrassed to say but I was testing the polarity of one of the led bulb to see which side was positive with a 12v battery and that’s when it decided to fry hoping I didn’t damage anything else
    • I came here to note that is a zener diode too base on the info there. Based on that, I'd also be suspicious that replacing it, and it's likely to do the same. A lot of use cases will see it used as either voltage protection, or to create a cheap but relatively stable fixed voltage supply. That would mean it has seen more voltage than it should, and has gone into voltage melt down. If there is something else in the circuit dumping out higher than it should voltages, that needs to be found too. It's quite likely they're trying to use the Zener to limit the voltage that is hitting through to the transistor beside it, so what ever goes to the zener is likely a signal, and they're using the transistor in that circuit to amplify it. Especially as it seems they've also got a capacitor across the zener. Looks like there is meant to be something "noisy" to that zener, and what ever it was, had a melt down. Looking at that picture, it also looks like there's some solder joints that really need redoing, and it might be worth having the whole board properly inspected.  Unfortunately, without being able to stick a multimeter on it, and start tracing it all out, I'm pretty much at a loss now to help. I don't even believe I have a climate control board from an R33 around here to pull apart and see if any of the circuit appears similar to give some ideas.
    • Nah - but you won't find anything on dismantling the seats in any such thing anyway.
    • Could be. Could also be that they sit around broken more. To be fair, you almost never see one driving around. I see more R chassis GTRs than the Renault ones.
    • Yeah. Nah. This is why I said My bold for my double emphasis. We're not talking about cars tuned to the edge of det here. We're talking about normal cars. Flame propagation speed and the amount of energy required to ignite the fuel are not significant factors when running at 1500-4000 rpm, and medium to light loads, like nearly every car on the road (except twin cab utes which are driven at 6k and 100% load all the time). There is no shortage of ignition energy available in any petrol engine. If there was, we'd all be in deep shit. The calorific value, on a volume basis, is significantly different, between 98 and 91, and that turns up immediately in consumption numbers. You can see the signal easily if you control for the other variables well enough, and/or collect enough stats. As to not seeing any benefit - we had a couple of EF and EL Falcons in the company fleet back in the late 90s and early 2000s. The EEC IV ECU in those things was particularly good at adding in timing as soon as knock headroom improved, which typically came from putting in some 95 or 98. The responsiveness and power improved noticeably, and the fuel consumption dropped considerably, just from going to 95. Less delta from there to 98 - almost not noticeable, compared to the big differences seen between 91 and 95. Way back in the day, when supermarkets first started selling fuel from their own stations, I did thousands of km in FNQ in a small Toyota. I can't remember if it was a Starlet or an early Yaris. Anyway - the supermarket servos were bringing in cheap fuel from Indonesia, and the other servos were still using locally refined gear. The fuel consumption was typically at least 5%, often as much as 8% worse on the Indo shit, presumably because they had a lot more oxygenated component in the brew, and were probably barely meeting the octane spec. Around the same time or maybe a bit later (like 25 years ago), I could tell the difference between Shell 98 and BP 98, and typically preferred to only use Shell then because the Skyline ran so much better on it. Years later I found the realtionship between them had swapped, as a consequence of yet more refinery closures. So I've only used BP 98 since. Although, I must say that I could not fault the odd tank of United 98 that I've run. It's probably the same stuff. It is also very important to remember that these findings are often dependent on region. With most of the refineries in Oz now dead, there's less variability in local stuff, and he majority of our fuels are not even refined here any more anyway. It probably depends more on which SE Asian refinery is currently cheapest to operate.
×
×
  • Create New...