- 291
- Oxfordshire
- Bread_45
Hi All,
I've noticed a potential error in some GT6 stock spring rates. Upon buying an S13 K's Dia. Selection '91, a car I had used a lot in GT5, I went to the GT6 settings menu and saw the stock suspension values (kgf/mm)
GT6
F 3.12 / R 2.97
Now I seemed to remember them being 2.0 / 2.0 in GT5, which got me wondering...
A quick google came up with:
http://zilvia.net/f/tech-talk/26680-s13-spring-rate-ride-height-guide.html
"Stock S13 (1990 FSM #'s)
Spring Rate - F : 2.0 kg/mm | 112 lbs/in (w/ sports pkg. 2.2kg/mm | 123 lbs/in)
Spring Rate - R : 2.0 kg/mm | 112 lbs/in (w/ sports pkg. 2.2kg/mm | 123 lbs/in)"
I then took a look at a MX-5, since they are well-loved cars and I thought I'd be able to find real life data for them too.
GT6 (Eunos roadster J-Limited (NA) '91
F 3.39 / R 3.07
Google:
http://users.telenet.be/miata/english/suspension/Springs.htm
http://fatcatmotorsports.com/FRC_1_6NA/FCM_MSDS_1_6NA.htm
A bit of discrepancy between the two references for a '91 manual, but in lbf/in we have either
164.17 / 96.94 (lbf/in) = F 2.94 / R 1.73 (kgf.mm)
or
154 / 94 (lbf/in) = F 2.76 / R 1.68 (kgf.mm)
In both cases the GT6 values are stiffer than the reference values, but seem very precise, they are quoted to 2 decimal places and aren't something round like "3.00".
So what is going on here? I wondered if GT6 was somehow quoting wheel rates, but I don't think this can account for GT6's stiffer values, as motion ratios for suspension aren't usually that much over 1 to give this kind of increase.
Has GT6 somehow mixed anti roll bar data into the stock springs? This would at least make the values stiffer as observed.
EDIT: fat cat website shows 55.1% Front Roll Couple for a '91 MX-5.
Using the spring values in GT6, 3.39/(3.39+3.07) = 52.5%... close.
Any thoughts? The default 0 camber and +0.2 rear toe has always been irritating, but this seems even weirder.
Cheers,
Bread
I've noticed a potential error in some GT6 stock spring rates. Upon buying an S13 K's Dia. Selection '91, a car I had used a lot in GT5, I went to the GT6 settings menu and saw the stock suspension values (kgf/mm)
GT6
F 3.12 / R 2.97
Now I seemed to remember them being 2.0 / 2.0 in GT5, which got me wondering...
A quick google came up with:
http://zilvia.net/f/tech-talk/26680-s13-spring-rate-ride-height-guide.html
"Stock S13 (1990 FSM #'s)
Spring Rate - F : 2.0 kg/mm | 112 lbs/in (w/ sports pkg. 2.2kg/mm | 123 lbs/in)
Spring Rate - R : 2.0 kg/mm | 112 lbs/in (w/ sports pkg. 2.2kg/mm | 123 lbs/in)"
I then took a look at a MX-5, since they are well-loved cars and I thought I'd be able to find real life data for them too.
GT6 (Eunos roadster J-Limited (NA) '91
F 3.39 / R 3.07
Google:
http://users.telenet.be/miata/english/suspension/Springs.htm
http://fatcatmotorsports.com/FRC_1_6NA/FCM_MSDS_1_6NA.htm
A bit of discrepancy between the two references for a '91 manual, but in lbf/in we have either
164.17 / 96.94 (lbf/in) = F 2.94 / R 1.73 (kgf.mm)
or
154 / 94 (lbf/in) = F 2.76 / R 1.68 (kgf.mm)
In both cases the GT6 values are stiffer than the reference values, but seem very precise, they are quoted to 2 decimal places and aren't something round like "3.00".
So what is going on here? I wondered if GT6 was somehow quoting wheel rates, but I don't think this can account for GT6's stiffer values, as motion ratios for suspension aren't usually that much over 1 to give this kind of increase.
Has GT6 somehow mixed anti roll bar data into the stock springs? This would at least make the values stiffer as observed.
EDIT: fat cat website shows 55.1% Front Roll Couple for a '91 MX-5.
Using the spring values in GT6, 3.39/(3.39+3.07) = 52.5%... close.
Any thoughts? The default 0 camber and +0.2 rear toe has always been irritating, but this seems even weirder.
Cheers,
Bread
Last edited:
