j9fd3s

iTrader: (3)

couple questions. i'm playing with paul ko's FD. 94, its on RB springs, stock wheels, 225's and everything else is shot.

1. its at 24.5" and its way low, it will come up, when we replace the upper mounts, which are shot, but still. how high can we go before its too high?

2. since this ones going to be more street than track, should i still set it too 1.2 negative camber? or would something less be better?

thanks! great thread

Howard Coleman

iTrader: (6)

yes, 24.5 is too low. since the FD has a race suspension it features 3 degrees negative camber gain from a 25 inch ride height at 2 inches of bump/compression.

there comes a point, just under 25 inches, where the camber adj cams aren't able to dial out enough neg camber to reach the static 1.2 degree preferred setting.

w the addition of new upper mounts you should be above 25 inches.

as far as what's too high i don't have an answer other than low is fast and 25 works fine on the street as well as track.

1.2 degrees neg camber works well on the street and doesn't overly eat up your tires.

hc

3rdGEN4MI

this is all great information for a person trying to learn as much as he can. Thanks!

MJay

Hi Howard. Thanks for your original post, I really enjoyed reading it. I have a completely stock series 8 fd type rs. I want predominantly a street car which isn't too stiff but could still be enjoyable on a track day or two. I am happy with linear dampening of the shocks, bilstein really got it right with the late model type rs. However there is a little to much roll. Should I start by getting thicker anti-roll bars front and rear and see how it goes, then move to a set of Eibach springs? WIll the EIbach springs affect body roll much, or more linear compression? Thanks heaps. Matt

Howard Coleman

iTrader: (6)

what size wheels/tires do you run Matt?

MJay

HI Howard. Currently on stock rims (235s front, 255s rear), but am hoping to pick up some CE28Ns in 8.5 and 9.5 (haven't decided on 17s or 18s yet). Dunno what goes best with these rims, maybe 245 and 275?

Howard Coleman

iTrader: (6)

size tires so the contact patch is the same size as the rim width. (sure, it is fine to plus or minus a modest amount re the above...)

Matt, or anyone, can you give me the spring rate for your FD version? i am not familiar w it as it wasn't imported here.

hc

MJay

My that could be hard to find...I'll have a look

zenofspeed

iTrader: (1)

The "perfect" match for 8.5 and 9.5 is 245 and 265. I personally run one step up at 255 and 275 and they work well. Any more than 255/275 would be a stretch.

MJay

Thanks! Yeah I'm still deciding between 17"s and 18"s. Anyone got any thoughts one this? Mainly after performance rather than looks.

zenofspeed

iTrader: (1)

As long as they fit your brakes, then 17s will be lighter. I got 18s to be sure.

I guess you'd see a marginal performance improvement on 17s vs 18s.. But I'm not sure it makes that much difference, as I've driven on both, back to back.

Howard Coleman

iTrader: (6)

setup fun in your garage.

camber

(anytime you raise or lower the car camber changes)


the first tool you need is a 6 foot piece of 3/4 inch aluminum square tubing and a couple of 3/4 inch cheap but exactly similar sockets. here's a handy way of keeping them together when not in use.




in order to accurately measure camber you need to determine the slope of your floor... thanks to the square tubing and my SmartCamber module i know i need to compensate .5 of a degree in front and .8 in the rear. (measure both front and rear.








here's the camber tool. the digital angle display easily separates from the frame and is used for tons of other things. don't forget to set air pressure before measuring camber.






sometimes the simplist of things can be such timesavers. i use this 25 inch piece of aluminum to quickly guage my rideheight.




toe settings can make a HUGE difference... after many years of using a tape measure i have graduated to a laser mirror tool. incredibly accurate.


the laser bounces off a pass side mirror and after you zero it you read the setting off the dial indicator and refer to a look up table.






here's the magic tool... my pyrometer has a memory and stores numerous settings. you can just as easily work w an analog pyrometer and have your crew write down the temps on a setupsheet.

tire temperatures tell ALL.



here are the 3 targets for tire temperatures on a Toyo. you want to see at least 20 degrees hotter on the inside. overinflation is indicated by a hot reading on the center. underinflation the opposite. oversteer/understeer is read by averaging the 3 readings from each tire. i could go on but will reserve until my track outing.





since we are limited to 10 pics per post it is time to turn the page.

howard

Howard Coleman

iTrader: (6)

here's corresponding pyrometer targets on my Sumitomo HTR ZIIIs



while not necessary a Durometer gives you the exact degree of softness as to tire compound. an unused HTR Z reads 66.



my used Toyos clock in at 68, just a touch harder.



since i don't have the garage/shop height for a lift my car has forever been on good old jackstands. there are times where it is really handy to have it elevated but on its wheels. here's my easy to make cheap solution.



milk cartons. i love them. back in my serious racing days a racer's net worth around the paddock was gauged by how many milk cartons he had. milk cartons have so many better uses than milk. just don't forget the interior support or you might end up in the emergency ward after they lift your FD off you.






the interior support.



you will probably need to give your jack a little help to get the car up and onto the milk cartons.



swaybar at rideheight, coil over settings all so easy thanks to the dairy industry




hc

jkstill

iTrader: (11)

I've seen Tanabe sway bars mentioned in this thread numerous times, and one post stated that their bars were about 30% stiffer than stock.

What I can't find is the same comparison for Suspension Techniques sway bars.

Does someone know how they compare to stock?

Sandro

iTrader: (1)

It's 114% stiffer than stock according to this comparison http://www.rx7.org/Robinette/antiroll_bars.htm


I have been using the ST bar for many years now and I am happy with it. I had the Racing Beat 1.31" modular hollow bar earlier. Then, one of the aluminum arms broke during an autox - I though the differential was gone as the rear right and left wheels started spinning alternatively like crazy...

I have been using the solid 1.25" ST since. RB doesn't sell the modular bar any more but a 1.25" solid bar, similar to the ST but prettier - painted in red. The RB attachment to the end link is also identical to the stock bar with the bolt connecting to the end link inserted full length inside the bar arm. With the ST you have instead to swap R and L end stock links (or - better - replace them all together with Mazdatrix adjustable links) and insert the connecting bolt at 90 deg. The 90 deg connection "acts" on a relatively small surface (across the holes) and inevitably leaves some play. You can add washers to make it tighter but the RB stock connection seems a better solution.

- Sandro

j9fd3s

iTrader: (3)

thanks much!

XxJaPxOxNeEs23xX

sorry just typing on here so this thread can be saved on my profile as a replied thread. I need it for reference hehe

glutton

thats deffaintly something im going to copy


if you go up to the top bars you will see "thread tools" click that and then a drop-down box will show up and you can select "suscribe to thread"

jeroentje.nl

So the reight height would be best when you meause 25 inch to the fender.

but I do not have a stock front fender on my car so could sombody measure what the hide should be where the front bumper meets the fender.

FCNAred

iTrader: (2)

would it not make more sense to measure from the center of the wheel to the fender? different people running different wheel and tire combos that have different overall heights are going to vary from ground to fender even if the suspension is "located" identically, no?

I just set mine up with 235 40 17 front and 245 40 17 rear at 25in and it looks really high to me. My previous koni/PFS spring combo was much lower in the front (too low i feel) and higher in the rear.

Howard Coleman

iTrader: (6)

FINALLY!!

i received my updated new generation FJO AI module which will allow me to get to the dyno and ON TRACK.

expect the thread to pick up speed shortly.

hc

fdrotor

Awsome thread totally changed my line of thinking towards my setup!

M104-AMG

iTrader: (8)

I just installed the FRP version of this wing, and I hope that the four bolts (2-each side) is strong enough IF this wing can generate some considerable downforce.

I noticed that the Spec '99 wing has a wider mounting base and more bolts, so I wonder if it distributes the downforce better . . .

I'm off to Roebling Road next weekend, so we shall see.

:-) neil

FWIW: I used the R1 template, and the distance between holes on each side was off about 1/16. Due to manufacturing tolerances, it is important to measure the distances on your specific version, but use the template for general location. Also, since it only uses four fasteners, there is no need to remove the hatch plastics. More info here:
https://www.rx7club.com/showpost.php...9&postcount=13

matty

when you lower your car how does that effect your alignment? does it increase or decrease camber?

Howard Coleman

iTrader: (6)

"when you lower your car how does that effect your alignment? does it increase or decrease camber?"

that's a great question matty. it has been covered but this is a long thread and since it is a key issue i thought it would be worthwhile to revisit...

as i have mentioned many times the FD HAS A RACECAR SUSPENSION.

that doesn't mean it has stiffer springs or bars. it means that as you move the suspension through it's various dynamics really unique (to most cars) things happen. these are the "things" that distinguish the men from the boys on the racetrack.

camber is one of the many key items.

the FD was designed w double A arms front and rear. by running a shorter upper A arm on bump a tighter arc is scribed V the lower A arm and the top of the tire is pulled inward more than the bottom and negative camber is produced.

stated more simply:

if you raise the tire two inches into the wheel well the tires goes from a static camber setting of negative 1.2 degrees to negative 3.7 degrees!!!!!!!

matty, as you lower the ride height you are doing the same thing... so your camber setting will change significantly. that is why i have always stated in this thread that if you change your ride height you need to re-adjust your camber.

as long as your steering rack remains in stock position, to a lesser degree, you might change toe settings.

why do we have "negative camber gain in bump?

you are entering a right hand turn on a road course. as you turn in the car rolls. the all important left front tire moves up into the wheel well in "bump." if you had no camber gain on bump here's the math.

static camber 1.2 degrees neg.
body roll 2.5 degrees.
dynamic camber in turn POSITIVE 1.3 degrees.

you always want your wheels negatively cambered otherwise you will have no grip. the double A arm FD suspension delivers.

static camber 1.2 degrees neg
body roll 2.5
dynamic camber in turn NEGATIVE 1.2 degrees

this in one of the many reasons that very few other chassis can touch a properly setup FD on a road course.

hc