Hi everyone.
I have asked this very question to Damon through PMs and he was very kind to put up with my repeated questions. I don't want to bug him more than what I have so far, so I am going to throw this out there for everyone to pitch in.

Here's my problem.
In my opinion, if you get a rim that has a +45mm offset to replace the +50mm offset on the FD, there is no way to fix the offset discrepancy.
When I emailed "The Tirerack" I was told that a 5mm wheel spacer will fix that. I don't think so, I think that it will actually make the offset become +40mm.
This is basically what I have been bugging Damon with.
If you could explain to me whether I'm right or wrong (and why I'm wrong if I am), I would really really appreciate it.

I am not trying to open up a discussion to win it, please understand. Just attempting to learn and/or understand.
I have attached a drawing I made to clarify my thinking.
The drawing shows three wheels. The first is the stocker (+50mm offset); the second is a +45mm offset (wheels I'm looking at, but it would not conceptually change with any positive offset that is less than the original stock); the third is the same wheel of the second example, but mounted with a 5mm spacer.
Legend:
Grey rectangle: wheel hub
Blue/green line: wheel/tire
Dashed Red line: centerline of wheel
Continuous green line: mounting face of the wheel
Yellow rectangle: 5mm wheel spacer
There are also two yellow lines that show the original position of the wheel with the stock wheel offset and a blue line that projects the location of the +50mm offset stock wheel along the other two wheels



To conclude, I think that wheel spacers only add negative offset.
So, if you have a +45 and put a 5mm spacer: +45+(-5)=+40
If you have a +55 and put a 5mm spacer: +55+(-5)=+50
If you have a -50 and put a 5mm spacer: -50+(-5)=-55
And so on so forth.

I hope I didn't miss this in my searches, If I did I apologize. I have been looking around for this type of info and I don't seem to find it clearly explained anywhere.
I thank Damon again for his help and I "pass the ball" to everyone that can and wants to help.
Naturally, anticipated thanks to all those who will help.
Giovanni

 

Wow, long post for a simple question. YOUR RIGHT, Tirerack is wrong. Adding 5mm of spacer to a +45 mm offset wheel will make it 40mm offset, NOT 50.

~Mike...............

 

i can't believe someone at tirerack gave that advice

 

I apologize for the length, but it seemed to be difficult to explain each other with the people I have talked to, so I tried to make it as clear as possible from the getgo.
Thank you, I really appreciate that.

Next question would be, how much will the 5mm change in offset from +50 to +45 do to scrub radius and what not?

 

Well, maybe they weren't thinking, as the exchange was more on why the wheels don't show at their site under the FD available wheels.

Here's excerpt, I am not going to put names up:

"Giovanni,

The Motegi Traklite is not listed as a proper fitment for your car. It may be the offset, but it also may not clear your brakes. Because I don't list it for your car, I don't have the ability for you to see the wheel on your car. If it clears the brakes you could probably use a 5mm spacer but we don't offer spacers for this application."

This was a bit back, I contacted after Auto RnD here as well. I have some time for these wheels, so we'll see.

 

they are ****** idiots. this just proves it.

a 45mm offset will be fine btw. i didnt see what size you were getting but you dont need to try to be the exact same as stock

 

Hi, and thanks for the help.
I am "stockish" (basically, DP and even cheaper bastard intake mod, which has now rendered necessary to install a boost controller, which is my next job), and -as much as I have something planned down the road- I don't intend to put down 400 WHp or anything close to that.
I would like to rather "refine", reduce weight, increase power reasonably and do "smart" things, like taking weight off rotating things and so on...
Anyway, I like the Motegi TrakLite I or II and in 17"x8" they weigh 14.5 (I have the 16 lbs stockers) and with the right tires can make for a 5.5 to 6 lbs weight loss per corner compared to what I have now, which it is interesting, at least IMO. They come with 45mm offset, so we're close, but not quite right on. I am a bit of a "need to know" and "need to understand" type of guy, so the entire discussion was primarily aimed at learning and understanding, with the purpose, in a very short while, to get some nice and useful wheels and tires.
On a different note, I was wondering if it would be possible to have them powder coated in a different colour, leaving the lip polished...

 

Just incase you don't know this, if your running into boost creep due to your "cheap bastard intake", a boost controller can only RAISE boost, not lower it. 5mm of offset won't upset your scrub radius too much, maybe not even noticable.


~Mike..............

 

Thanks for the info.
Somebody else has told me that about the boost controller. I thought I can place the boost controller on and set it to 10, which would be not raising nor reducing...
Rotaryresurrection said the same thing to me and advised me to either remove or drill the pill or -if I remember correctly- to unplug the wastegate solenoid.
But as far as I know this will simply kill the boost down to 7ish (not the drilling, that would work, but how do I know it's the right amount...).
I guess we're "off-topic-ing".
Giovanni

 

IMO, you should go for more width when buying new wheels. You can find x8.5" or x9" wheels that weigh only a little more than those Motegis.

 

I agree on the width too. I've driven stock FD's with sticky stock sized tires and 1st and 2nd just roast them. If your gonna upgrade, then upgrade!! get at the minimum 8.5 wide. Just wait till your making in the 320 hp neighborhood, you'll be hating life with stock sized wheels/tires.

~Mike..........

 

yea honestly thinking you will gain any noticable performance from lighter wheels is pretty ricey. especially if it means running bitch sized wheels. go a little wider, in the rear at the very least. you wont be able to tell the difference and the wider tires will help you a ton more than lighter wheels ever would.

and its preference, but motegi wheels suck. good light wheels i would suggest are 5zigen fn's, or a little more $ and get rpf1s. but thats up to you.

 

Thank you all guys.
I can understand the suggestion regarding going to a slightly wider rim to accommodate a wider tire. I am not running stock width as it is, since when I purchased the car it was (and still is) equipped with 245 45 all around. I thought I could go up one size in wheel diameter and stay with the 8" width and be OK. I guess I should do a search in regards to what kind of wheel size goes with what kind of power.

In regards to the wheel/performance gain, I beg to differ.
I don't see this car as a drag race car (and I can't stand drag racing, BTW), so to me anything that improves handling, acceleration and braking is an intelligent modification. I have calculated that doing this change (those wheels and contis or Pirellis) I could shave off at least 5.5 lbs per corner or actually more. Now that is an overall weight loss of 22 lbs on the car, loss that happens to be on rotating masses which don't only need to accelerate, but also need to stick to the ground and slow down as well. I don't see why this is ricey, while buying a wing -any wing, even functional ones- shouldn't be. Not to mention a CF hood, which will spare you one pound or the hatch that -as far as I know- will spare you just as much as this idea of mine, with the difference that the hatch is dead weight your car carries around, while the other is a rotating mass. Certainly, I don't think that anybody can expect a weight loss mod to feel as good as adding 2 lbs of boost, but sometimes little things make for great satisfaction. I have had the wheels changed on several other cars I have had and anytime there has been an increase in wheel weight, I have known it and haven't liked it.
Maybe it's just me.

 

^I'm with you on wheel weight. On my corolla I felt a difference from running konig rewinds to black racings. But now I'm kinda paranoid about breaking a rim while driving.

 

Nicely written post, gio64. Talk with Rishie about your needs. He knows the fitments and will find the right wheel at a great price.

 

Thank you for the suggestion.
I have however already talked to him in regards to these wheels.
I am still looking and I am still evaluationg options, I don't necessarily have my head set on that. As a matter of fact, this story about going up in width has me a bit worked up, because I don't see really going any bigger thant 245 on a 8" wheel, so I am going to find out when 245 is not enough in the back any longer... I wonder if there is anything like that on the board...
I'll have a look.

 

IMO, I don't see a problem with a 17x8 wheel. I don't believe everyone needs a 10" wheel on the back of their cars or needs to upsize everything. I plan on tracking my car with either a 17x8" or 8.5" wheel. Why? Well, I'm not competing and tires are much cheaper in the 245-255 range.

gio64,

Post back if you get the Motegi TrakLite wheels. I had thought about those myself.

 

I probably will, I can't seem to find anything else that light! Hopefully they won't cave in...
I have just finished a relatively short search on tire size/wheel width issue.
So far this is what I've learned: a 17"x8" wheel is recommended (at least by Yokohama) to take up to 245/40 17 series tires. If you want a bigger tire, they suggest to go with 8.5. In this case, I think you can fit a 255 (I believe) on the wheel.

My only concern is whether or not 245s will be appropriate for, say 300/320 rwhp. I don't have that, but I'd like to work towards that, so that's what I'm trying to sort out.
I have also learned that wider wheels do increase the width of a tire and reduce the sidewall height a slight bit, so the same tire will put more compound onto the ground if it is seated on a 9" width wheel as opposed to an 8" width wheel. You probably knew this, but I didn't, so I figured I'd post it.

On a different note, I was wondering if you know any other wheels that can be used on 17" size and that are lighter than the stockers (I have the "heavy" stockers, so my mark is 16lbs, however, considering that the 17" wheel displaces a considerable amount of its mass further away from the centre of rotation, same weight wheels in 17" would be actually more difficult to spin anyway...).
I was only able to find the following:
Rac Monolites RS110 13.1
BuddyClub )1 Racing QF 13.6
Racing Hart CP-035R 13.6
Toybox 48 Hehtel 13.7
Stern Aguzze S07R 14.0
SSR Type-C (competition in the US/Canada) 14.3
Motegi Tracklite I and II 14.6
Racing Sparco LE 14.6
5Zigen Becketts FN01-R 14.7
Wed's TC005 14.9
Enkei RPF1 15.6? (I found three different weights for these wheels: TireRack lists them at 14.5, Wheelweights at 15.6 and some other place at 15.8... What's right?)
My Yokohama tires should (I cannot find definitive information) weigh in at 26/27lbs.
Continental Sport Contact 3 come in at 21lbs
Pirelli PZero Rosso come in at the same weight.
Note that all the weights I listed refer to 17"x8" wheels and 245/45ZR17 tires.

If you have any other suggestions as far as wheels go, I'd be interested to hear them.
Giovanni

 

This is how I justified 8.5 or 9" wheels. IMO, you're much more likely to want to try wider tires, not narrower. With 8.5" width, you can run 225-255. (The later JDM RX-7s ran 255s on 17x8.5" wheels...) A 17x9 supports 235-275s, which includes all of the likely 17" sizes for an FD. As you pointed out, gio, tire weight is more important than wheel weight, so gaining 1 pound per corner with 17x9s sounds reasonable.

I bought RPF1s in 17x9 +45 from Rishie. Unfortunately, I don't have a scale, but the RPF1s with 255 RA-1s feel very close to my stock wheels with 225 GS-D3s. I realize that's not a concrete assessment, but I am confident that the weight difference is essentially meaningless for my lapping-day use.

 

I understand. I would like (I know, I sound obsessed, sorry) if there is anyway to figure out adequate tire sizes based on car weight and power output. Any ideas?


Thank you for the info. I am really surprised that there are so many different numbers circulating about this wheel. I like it, but I like the Motegi TrakLite I (5 spokes) a bit better, as I think it has a bit more lip.
I was going to dive into the RPF1, but then I couldn't find the weight...
We'll see.