Skifey wrote:Oh my god. Kill me. My wheels are 15x7 not 15x8. I have no idea why I thought they were 8"! I'm such a muppet - sorry guys! This means as well that my offset is incorrect as I was going off the Enkei chart. It's going to be either 35mm or 41mm. I'll confirm that as soon as I'm home! My bad team!
Skifey wrote:Sorry for the delay guys, alignment report is below
Now! It seems the consensus is that the heart of my problem is my tyres rather than my suspension... Are you sure I simply can't raise the car up? Why cant I just set the ride height at a point where maximum suspension travel is a few mm from the guards? I don't fully understand why this isn't possible. Practical sure, but possible? It makes sense in my head or am I thinking of it completely wrong? Amateur here
As for the chinese Goodrides; yes I know. Trust me, their existence is an apocalyptic burning pit of disgust and misery in my life. I was after the Enkei's not the rubber and I figured I'd just get a bit of use out of them before discarding them. So little did I know about tyre sizes, diameters, rubbing and all of the other problems I've never experienced prior to this
I was always intending to jump onto a set of Potenza RE003's just because they seem like the go-to tyre although they are only made in 195/55/R15 or 205/55/R15 and naturally I want to stay as wide as possible... because yes it looks cooler - guilty as charged haha. What other tyres can I run that are are 205/50/R15? The AD08R's Magpie's talking about is one option, are they commonly used? I don't mind going wider if that's even a good idea - like say a 225/45/R15 although again I have no idea as to which tyres are a good idea to use in that size.
Yes tyres are your biggest problem for rubbing issue which you now are acknowledging.
Now that we know that your rims are 7 inch, I would say go with the very common and cheap 195/50/15's. Save lots of $$$ over 205/50/15.
This will likely fix up your rubbing issues without even rolling the guards.
No problems running that size on 7 inch rims. With an 8 inch you would be joining the stance club.
Also RE003's come in 195/50/15. Take advantage of the 4 for 3 offer this month.These tyres won't disappoint.
The pic of your car just looks like the tyres stick out heaps more than a +35 or + 41 rim. The bulgy 55 profile tyre may be contributing to that.
Just for reference a tyre with the same section width, but higher profile will be more bulgy and wider. Not the tread, but the actual side wall will bulge out more.
Ie 205/60/15 wider than 205/55/15 wider than 205/50/15 wider than 205/45/15 etc.
Regarding your alignment.
First off don't get it redone until you fix your shock leaking issue.
They have set it up for road use regarding the crown in the road. Its OK but not the best.
That generally means a little more camber and caster on the front left compared to the right to reduce the requirement of steering right to keep straight.
I set my car up the same left and right because it is for track so I don't care so much about having to steer a bit right on normal roads.
Front settings.
First off they have given you more toe in. More toe in (more positive number) which makes the car more stable.
If it were me I would want 0.5mm or even 0 each side for the front toe. This makes the car feel less stable but more like a go kart handling wise.
Not enough front negative camber. Plus the difference between left and right is too big. They did reduce the left to help, but should of increased the right as well.
More negative will help with guard clearance and bring it closer to the rear setup
Maybe 1.5 degrees on the left. Your data sheet is using degrees and minutes so 1 degree 30 minutes. (60 minutes is 1 degree). 10-15mins less on the right. 1 degree 20 minutes.
They have reduced your front left caster. Which is OK because it was too different to the right one before.
Caster affects how easily your steering self centres.
If you have no power steering, the greater the caster angle, the heavier the steering is. Also the greater your caster, the less negative camber you can have.
So there is a trade off. Rule of thumb is 4 to 5 degrees for a NA/NB MX-5. Can be as low as 3 degrees if you have a NA with really wide tyres and no power steering.
Rear End
If you look at your before figures they have not even touched the rear end at all.
Lucky for you that the rear had a lot of negative camber already other wise you would have destroyed the rear tyres on the guards by now.
I would say there is too much difference between left and right on the rear. 10-15mins would be more acceptable, not 45mins as it it now.
Around -2 degrees is more than enough for a hard dríven road car. -1 degrees 30mins is more where you should be, but will depends on clearance.
You do want toe in on the rear. +0.5 to +1mm on each side is pretty much where you want it to be.
Now back to coilovers.
I think the same model coilover sits differently in a NA and NB in the rear end. Can someone correct me on that???
I think one sits higher than the other, but I cannot remember whether NA's or NB's sit higher with the same unit.
The front is the same.
Now here is the problem with Tein Street Flex, which is the same spec as Flex Z.
In my NB at Maximum height set at the rear, I am lower than your NA is now.
The biggest problem with that is the least amount of negative camber I can get in the rear is -2 degrees 10minutes with a sensible toe of +1mm. Any less camber and the toe just goes more positive(In).
Rear height adjustment is the biggest problems with the Teins on a NB at least. I can go 50+mm lower which is just useless.
The fronts have better adjust-ability range, but because the rears are so low, I had to match the fronts to suit.
Also, regarding setting other units up high to avoid guard rubbing, I don't think there would be many systems out there that would even go that high that you could buy off the shelf. Even with the standard suspension fitted the tyres push up into the guards when loaded.
There are a few ways to reduce the total travel upwards, but most will affect the already limited travel NA and NB MX-5's have in the rear.
Longer bump stops. You will feel every time you bottom out on them.
Really stiff rear springs. You would then need stiff front springs as well. This would be OK on a race car with downforce, but not a road car.
So like everyone keeps saying and you are acknowledging, tyres will be your biggest fix for the rubbing issue, regardless of what springs/shocks you fit to fix your leaking shock.
195/50/15 will solve most of your problems.