Page 1 of 1
Speed Limiter removal on NA Eunos
Posted: Tue May 07, 2013 4:41 pm
by Gladiator
I've been wondering how to undo the Jap speed limiting, and I found this
http://www.mx5oc.co.uk/forum/forums/t/34933.aspxI'm hoping to do it before the QR track day, so I'll let everyone know how it goes after that. They are supposedly limited to 180Kph but I hit the limiter on the straight at Lakeside at about 165Kph.
I'd be keen to hear anyone else's experiences on this topic.
Re: Speed Limiter removal on NA Eunos
Posted: Tue May 07, 2013 4:50 pm
by Gladiator
Re: Speed Limiter removal on NA Eunos
Posted: Tue May 07, 2013 7:16 pm
by project.r.racing
IT's the same for Familias of the same era. So I'd say it's probably spot on that info.
Re: Speed Limiter removal on NA Eunos
Posted: Tue May 07, 2013 7:22 pm
by Magpie
You will probably find that the wall you hit was the amount of HP/frontal area required to push the car past the 160. I hit 160 at lakeside however the angle of the rear wing combined with the gurney flap probably caused top speed to suffer but it was more not enough HP and enough straight to get beyond 160 (NA6).
Need to confirm these values, but
Drag coefficient 0.36
Frontal area 1.64m2
Speed 180k
You need 62.7 HP just to overcome drag.
Re: Speed Limiter removal on NA Eunos
Posted: Tue May 07, 2013 9:07 pm
by Gladiator
Magpie, while I was pretty much flat out, I did actually hit the speed limiter. It scared the sh@t out of me. I thought I'd broken something at first. It made horrible noise, & I don't know but I wouldn't think that's too good for the car. Anyway, I dont need any exta limitations.
Re: Speed Limiter removal on NA Eunos
Posted: Tue May 07, 2013 9:35 pm
by Magpie
I stand corrected then as I did not hit a speed limiter and mine is an import as well. Let us know how you go as I may have to ask after my engine is installed.
Re: Speed Limiter removal on NA Eunos
Posted: Tue May 07, 2013 10:49 pm
by koop21
My thoughts on watch that video you linked appears it only affects people with stock ecu, so Magpie i dont think you have anything to worry about.
Re: Speed Limiter removal on NA Eunos
Posted: Wed May 08, 2013 7:03 pm
by Magpie
Well I just used a program called GIMP to calculate the frontal area of my NA (the wing is now at 5 deg) and it worked out to 2.10 m2. I'm still to work out the Drag Coefficient (Cd) but using 0.36, I would need 75.7 HP to overcome drag alone. So to do 180 in my NA I would need approx 85 HP to get 180 down the main straight of Lakeside. 220 would require 151 HP (approx).
Re: Speed Limiter removal on NA Eunos
Posted: Wed May 08, 2013 7:14 pm
by Gladiator
What if your going with the wind up your arse?
Re: Speed Limiter removal on NA Eunos
Posted: Wed May 08, 2013 7:16 pm
by Magpie
I'll load up on some baked beans to give an assist next time
Re: Speed Limiter removal on NA Eunos
Posted: Wed May 08, 2013 10:23 pm
by timk
On the NB you can remove the VSS going into the ECU, its either pin 2D or 3D. Not sure what else this does but who cares; because racecar!
Not sure if this is any use on the NA.
Re: Speed Limiter removal on NA Eunos
Posted: Wed May 08, 2013 10:25 pm
by timk
You get a bit over 180 before it happens in an NB, too.