My car has a full size optima, in the trunk. So I moved 50lbs from the front of the car to the rear. I weighed it with the spare and jack in place.


Only difference on the EU cars is AYC and the the ACD/AYC pump being in the back (I think). Not enough to make weight bias that good. And I don't think ride height would account for the either. A stock USDM Evo sits level...

 

Yes, correct the ACD/AYC pump sits in the back where the EVAP and charcoal canister is on our cars...Im pretty sure the AYC rear diff weighs more; I know its larger in size so I'd image it weighs a little more. But not much and the ACD pump doesnt weigh that much either though I don't have a weight off the top of my head but I can say its gotta be <30# with pump and stock bracket. Im just about done moving mine to the trunk but dont anticipate there being much of a noticeable difference; I just wanted it in my trunk so it would stay protected from the elements.

Changing ride height has some impact thats how cars are corner balanced. However I can't see it making that much of a difference unless you literally jacked up the front and slammed the rear

 

That's what I mean, your front ride height would have to higher than the rear. And USDM Evo's come level, so I'm not sure the EU Evo's sit nose high...

 

I doubt a factory car sits any higher than the US spec one. Plus he is on Ohlins and I dont even think you can set them to stock height. I mean you could probably go with a 10" spring and even some spacers between the top hat and the strut tower but that is not the case here.

I don't own a set of scales so I've never played around with different heights relative to corner weights but I just can't see it making that much of a difference.

 

The stock suspension sits level. Oem springs plus KYB shocks.

My car has no canister, no sunroof and if it had electrical foldable mirrors and auto HVAC it would be almost a JDM spec.

I was expecting a 60/40 ratio just like you all said. When I got the call with the final suspension settings I was kind of amused. When I have the chance I will weight it with the stock suspension.

You would be amazed with a VIII RS-II I have. It has ACD, Brembo brakes, no ABS, front lsd, rear clutch diff and my ear scales tell me it is at least 40kg lighter just due to having no sound deadning. When I first drove it I got crazy with all the noises. I swear you can hear the injectors and valves from inside.

Back to the topic, I will consider using a higher spring rate on the back. The drawback is that there is no Ohlins dealer in my country so revalving will be a hasle.

 

no need to revalve... just put some 9K springs in the front and use the 10 K in the rear. We have one car on 8/10 and that one is a bit tail happy for some people.. esp with AYC..

 

Where do you use that setup? Autox?

 

So the scales show 1488 which we know is 3280# However you mentioned when it was scaled that it had a full tank of gas and a 154# mechanic in the seat. Now I believe the euro spec cars with AYC have a smaller gas tank ~10gallon but dont hold me to that but even so 10 gallons vs 14 were talking a difference of 20# in fuel.

But anyway so your car weighs just under 3100 which is light for minimal weight reduction, no doubt. However it still doesnt explain the awesome weight distribution that your scales are showing so I am still stumped. Once again I am not calling you out so apologize if Im coming across as argumentative; certainly not my intentions. I just don't get it something isn't adding up...

Anyway I think this thread has gotten completely off topic. The general rule of thumb is +/- 4k before a revalve is needed. Of course a revalve would be ideal for every rate change but its not necessary with a quality damper like your Ohlins. So if I were you I would pick up a set of 12k for the rear throw those on and see how the car feels for now. I went from 8K F 10K R to 10K F 12K R on stock valving and then finally went to a 12K 14K with a revalve. You mentioned excessive nose dive on braking so I wouldnt go any softer in the front. The only way to keep the nose up is stiffer springs sway bars also wont help with that.

Youre going to need to eventually send in your shocks for service so that may be a good time to get them revalved. Unfortunately you dont have local support so it may take a little longer but Ohlins USA is located in North Carolina so theyre not that far away. Throw on the stock suspension for a few months in the off season and call it a day.

 

This sounds great. I will get the springs. Already bought a stiffer front sway bar and a cusco adjustable front sway bar bracket so I can dial the sway bar easily at the track.

Back to the weight topic, being a modified EDM Evo VII, my car:
1- has no crash bars
2- has no charcoal canister
3- the acd/ayc pump is on the back
4- might have a slight lighter soubd deadning
5- fuel tank capacity is 48 liters / 13,3 galons.
6- Has a Perrin intake, much lighter than stock
7- has a light regular sealed lead battery wich weight around 14kg/30lbs
8- has an AMS intercooler
9- has no balance shafts - I removed both
10- has no undertray / splitter
11- has no catch cans
12- has a greddy ti-c catless exhaust witch is lighter than stock
13- has no crossbars on the front subframe (I know it hurts on cornering)
14- interior and trunk trim are untouched.
15- audio wise just an Alpine HU and front speakers.
16- engine wise I haven't added any considerable weight. Even the rods were choose by their weight (carrillo)

Maybe if we add it up things will make sense.

 

Agreed, there's no way that distribution is correct. I don't know why he has those results but getting near 50/50 on any evo is a pipe dream without absurd rear ballast.

 

road actually.. I suggested my friend to get some 9K springs for the front but he said he is happy with the way it is now.. on the track the car sort of balances itself when the tires heat up.. but he uses road tires, not semi slicks
Problem is, with ayc the car is very nervous on lower speeds.. we both like it, but it is not for everyone..

I specced 8/9 for my car, for the road..

 

I know exactly what you are talking. When I step on the gas on low speed corners I can feel the rear outside wheel pushing the car. As the speeds increase the car loses that behaviour.

I think the X is tail happy even on higher speeds. Must have something to do with the revised S-AYC.

 

I would say that the X has better front end grip... as for ayc it works similarly in my experience.. actually X is more neutral for me..

we did try the 9 on ohlins stock reccomendation of 10/8 and it was nice on the road.. but understery on slow tracks. And we did run stiffer rear ARB.
I actually got into an argument with Ohlins UK about the spring rates.. accusing them of just copying the X spring rates without taking into account the different rear motion ratios of the two cars..

As I said.. I think the sweet spot is somewhere around 9/10, 8/9, even 10/10.. whatever you like.. not such an expensive experiment after all.