Section8

iTrader: (6)

Ok, I had my car aligned today since I installed my Eibach springs last weekend. Here's what I asked the shop to dial in:

Front
1/16" toe in
-1 Camber
6 Caster

Rear
0 toe
-1.25 Camber

When I picked the car up, the guy told me the left rear wouldn't go any further than -.5 camber . Everything else dialed in fine. The car was already off the rack so I couldn't have him even out the right rear (they were closing and I wanted to get home)

1st question: Why wouldn't he be able to dial in the full -1.25 on the left rear? Could the guy be incompetent, or could there be a problem with my suspension? He mentioned that maybe the car had had some problem (hit a curb?) in the past that may have knocked it out of whack,

2nd: Will it have a major effect at an autocross? I realize these settings will chew up tires, but I'm willing to sacrifice that for better handling, but I'm wondering what having the rear camber at different settings will do.

rynberg

Those settings are very conservative with 16" wheels, I don't know why you think you'll chew through tires. As far as the alignment issue, take it to a REAL shop -- a local performance/race shop that knows how to really do an alignment.

I also don't agree with your desired settings. IMO, you should never have higher camber in the rear than in the front. Your toe settings look fine though.

When I ran 16" wheels, I used -1.5 camber in front, -1.3 camber in back. No excessive tire wear.

Howard Coleman

iTrader: (6)

i am a bit unclear as to your current rear settings. did the guy set one rear corner at -1.25 and the other at -.5 or did he equalize the rear at -.5?

i am also scratching my head as to why he couldn't give you the setting you requested. when you lower an FD the suspension goes into negative camber due to the unequal A arms. i agree w Rynberg ( as i usually do) that you should eventually find a better shop. the FD is an easy to align car and it appears you are dealing w someone riding perhaps a learning curve.

as to settings..... yes they are conservative. you will not "chew up your tires" w 1 and 1.25 camber. those settings should work well on the street and track together. as to Autocross, that's a different story. Autocross suspension dynamics are different than street and track. i have never done Autocross and my background is 22 seasons of SCCA National road racing. my guess is that Autocross requires more camber, more roll stiffness etc than road racing.

as to more camber in the rear... the FD is a front engine rear drive car. as such, the primary limiting factor as to going fast on a road course is making the rear end stick. the rear needs to be softer in every way compared to the front. it also needs more camber. at the track i set my camber w a pyrometer. the pyrometer tell me exactly what each corner of the car needs camberwise. ( it also tells me tire air pressure ). if you don't use a pyrometer you are close to blind as to chassis tuning. i always end up running more camber in the rear on the track. for the street, however, i recommend 1.2 front and rear.

Rynberg suggests 1.5 and 1.3.... sounds just fine to me since there is little difference.

congratulations on making a good move as to springs. i hope you like your Eibachs as much as many of my friends do.

air pressure measured cold for aggressive street and track 30 fr and 28-27 rear.

howard coleman

Section8

iTrader: (6)

Thanks for the replies guys, I'm new to all this and I was just thinking that a lot of camber would wear the tires faster.

i've gotten a few replies from the rx7 big email list too, and I'm currently searching for a decent shop. The shop I went to was the only place I could find in a week that would even consider doing an alignment that wasn't to manufacturers spec.

As far as the settings I used, I got them from http://westpenn.rx-7.org/Files/FD_Align.html using the 'long track' settings for my stock 16" wheels and at the suggestion of friend and long time FD owner I backed out .5 negative camber from the front, and I didn't ask, but I think his rational was to try to give me a good mix between autox and track since that's what I'm planning on using the car for most. I need to touch base with him about that again.

Howard, what the current rear settings are as far as the guy told me are -1.25 left rear, and -.5 right rear ( i switched up the sides in my original post) I'm not sure why he didn't even it up. They guy was very nice and professional, and admited to not knowing much about suspension dynamics, so I don't really blame him but this is the only shop so far I've found (at least in a week of looking) that would align out of factory specs.

Joe

DamonB

If your car is truly limited to only 1/2 a degree of negative camber at the rear then something is big time bent. I find that hard to believe. OTOH I also find it hard to believe that the alignment guy can't get the rear end right. We're literally talking about just one bolt. I'd get a second opinion from someone local who does performance alignment work. I use my local NTB as the guy running their rack is top notch and he understands my car is a "racecar". My only concern is for him to match the specs I give him and he always does an excellent job.

1 degree of negative camber isn't a whole lot. It will wear tires faster than 0 camber, but not near as fast as something closer to 2 degrees negative. I run about 2 degrees negative at all four corners and I definitely get only half the tread life out of my street tires that I should. That's the price you pay for setting the car up for competitive events and then driving it on the street.

I have also found that running up to 1/8" of rear toe in helps this car a lot. The rear toe helps pull the *** of the car back under you when on the power hard out of corners. I find the car much more willing to power out hard with rear toe in.

Section8

iTrader: (6)

Well I just talked to John Duff and he recommended Performance Buyers Club near me, said they understand FD's very well and do great work, so I'm going to call and setup an appointment there.

I'm going to go ahead and keep these settings, although maybe i'll bump the front to 1.5 negative camber. I'm still so green in the seat that I probably won't be able to tell much difference anyway :p Once I get better I'll look at playing with rear toe-in as you suggest Damon

Thanks Damon

Howard Coleman

iTrader: (6)

i agree w Damon as to rear toe.

your alignment guy made a major mistake by not equalizing your rear camber settings. the car could be a bit unsettled under both braking and acceleration. i also seriously question why you can't dial in more rear camber than .5. either the guy didn't know what he was doing or the suspension is seriously messed up. your Eibachs create negative camber alone since they lower the car and the suspension is in "bump" versus stock ride height.

finally, make sure you have zero rear thrust angle.

howard coleman

Section8

iTrader: (6)

Thanks again Howard. I'm really just hoping that the first guy just didn't now what they were doing. I'm going to try to get an appointment as soon as I've got time at the shop that JD recommended and hope that they can sort out whatever the other guy did. Hopefully I can squeeze it in before the 4th when I have my next autocross.

Maybe i'll go ahead and have them throw that 1/8" toe on the rear too as Damon suggests. I'll report back once I get the work done.

Joe

Howard Coleman

iTrader: (6)

alignment of the FD is extremely simple to do. any, repeat any, reputable alignment shop will find it a walk in the park.

there is no reason to pay any significant premium for FD alignment, so don't let some tuner shop smoke you on it. talk to the shop and tell them you want a before and after printout. tell them you want it aligned w 30 psi front and 28 rear air pressure and give them your alignment specs. don't forget the zero rear thrust angle.

good luck,

howard coleman

Section8

iTrader: (6)

One more question, the zero thrust angle is only for the rear correct?

DamonB

Yes. Thrust angle is essentially the front and rear axles being exactly parallel to eachother. Obviously if the rear axle were not parallel to the front the car would wish to drive in an arc. You could still make the car travel straight by then adjusting the front but then the car would "crab" sideways down the road. Zero thrust makes certain the rear follows exactly behind the front when traveling in a straight line.

Section8

iTrader: (6)

You guys are probably getting sick of my questions, but I've got more

Ok, i'm getting conflicting suggestions from people that all know what they're doing, and seeing as I don't know what I'm doing I want to get this sorted out.

In this thread you guys suggest 1.5 front and 1.3 rear negative camber, but in an email I got from Paul Winter via the big list, he says:

Now, he's referring to a street setup, and I'm interested in a street/autocross setup that will also work well when I get to do an HPDE (if such a compromise can be reached)

That being said, I still don't have a lot of seat time, so should I go more conservative until I get more experience, or just go with what you guys have already found to be "tried and true" ?


Thanks a lot guys, I really appreciate you helping a newbie out.

Joe

rynberg

I experienced zero problems running 1.5 camber. The only negatives to high camber are reduced straightline/braking stability and excessive tire wear. I experienced neither at 1.5 deg. Paul's camber suggestions look good for an 18" wheel and are in fact, almost exactly what I am running on my car.

DamonB

No offense to Paul Winter on the big list but I have not seen an FD yet that has trouble with the rear end rotating. In fact nearly every single newb driver has troubling keeping the rear end from rotating!!!! He's recommending how to fix a problem that doesn't exist.

I run 1/8" of rear toe in and it does not hurt my turn in at all. Compared to zero toe on the rear I can get on the gas more agressively out of the corner without breaking the rear end loose and having to countersteer. It also makes the rear end of the car more forgiving when under power and that is something that absolutely helps this car, especially when you consider the sequential turbos.

I've tried many, many things with this car and 3/16" of rear toe in makes the rear even more stable; too stable for my tastes (and it will eat tires MUCH more quickly).

Howard Coleman

iTrader: (6)

Paul is correct as to the FD not needing much static negative camber... unlike BMWs and Porsches which use an inferior front strut suspension, the FD features a racebred double A- arm front. as the outside wheels move in to "bump" position the unequal A-arms add negative camber to negate body roll.

that's why we are talking 1 to 1.5 degrees camber set static.... not 2-3 degrees as you would run on a BMW etc.

i fear you are getting a bit confused when it is pretty simple. firstly, whether it is 1 degree neg or 1.5 degrees makes little difference initially. i recommend 1.2 which is in the middle. you need just the slightest toe in both in front and rear. less than 1/8th or thereabouts. castor should be equal and minimzed in my view. thrust angle xero degrees.

tire pressures are VERY imprtant as to going fast and should be the first thing you mess w at the track.

beyond all that... at the track to go faster you need to spend around 100+$ and get a pyrometer.

at the track i set my suspension looking at pyrometer (tire temperature) readings and don't even reach for my digital angle guage.

howard coleman

adam c

iTrader: (2)

Welcome to the real world. There are very few topics where all the experts will agree on anything.


[/QUOTE]That being said, I still don't have a lot of seat time, so should I go more conservative until I get more experience, or just go with what you guys have already found to be "tried and true" ?[/QUOTE]

You have done a lot of research, which is a good thing. On this paticular thread, you have received advice from some of the best people on this forum. I suggest that you set your specs to something "average" of the advice you are getting. You will find that your setup will be very good, and will go a long ways toward helping you go faster. Once you are more experienced, you will be able to make minor adjustments that may suit your driving style. Of course, you will have to establish a "style" first

Section8

iTrader: (6)

Once again, thanks alot gentlemen, I really appreciate the advice. I think I'm straight now

Howard, you mention using a pyrometer to set your suspension at the track. Do you do on the fly camber ajustments when you go to the track? Are the adjustments on this car that easy to dial in by yourself once you're familiar with the car?

Howard Coleman

iTrader: (6)

i don't know what on the fly means but i generally do 3 laps or so and then check tire temps. based on the reading i then adjust camber and/or tire pressure.

camber adj is easy to do at the track once you have done it a few times.

i suggest that you go to the track and drive-drive the car. get lots of laps.

come in every so often and bleed air out of your tires back down to the 30/28 area. the first chassis tuning you should do is getting acquainted w tire pressures and the major role it plays.

howard coleman

Section8

iTrader: (6)

Well I just got the car aligned at Performance Buyer's Club, and it's like night and day. First of all, there was nothing wrong with my suspension. 2nd, the first shop must either really need to calibrate their equipment, or the guy was a complete dolt. Here's what was on the car when the guy checked it today:

Front Left Camber -.6
Front Left Caster 4.8
Front Right Camber -.7
Front Right Caster 7.4
Rear Left Camber -2.9
Rear Right Camber -.9

0 Toe front and rear


Obviously not anywhere close to what I asked for, and what he TOLD me he had gotton. In fact, he told me he got all but one wheel right, when it looks to me he got all but 1 wheel wrong. And no toe either.

David at PBC set me up with this:

Front (both sides equal)
Camber -1.2
Caster 5.8
Toe 1/8" in

Rear (both sides equal)
Camber -1.2
Toe 1/16" in

The car now drives like a dream, for the first time since i put the Eibach springs on, I can really tell a difference in the performance of the car.

Thanks so much to all you guys for your help, if we ever meet up sometime I owe you all a beer

-Joe

t-von

iTrader: (8)

So are those above specs ideal for an Fd with lowering springs and stock rims? What about with 18's? Also I tried to locate the Pettit racing alignments specs but the link no longer works. I have some 18's on the way and would like to get the proper alignment specs w/ Eibach springs.

AntiVenom7

my understanding(from what I've read on the forum & a couple of books) is the bigger wheels and wider tires need less camber; is that correct? What are good street/track settings for a 7 with 18's? Thanks.

DamonB

Generally that's true. Wider, lower profile tires won't need as much negative camber as narrower, higher profile tires.

AntiVenom7

http://www.jimagu.com/tinou/pettit_alignment.jpg

Here's the latest Pettit specs.

They are recommending .8 Front Camber and 0.0 Rear Camber. That seems a bit conservative to me. Any opinions?

DamonB

My opinion is everyone second guesses stuff they know nothing about Why are you adding negative camber in the first place and what is it going to do for you? Why do you think you need more?

There is no such thing as a good street/track compromise. One that's good for the street will give up performance at the track and one that's good for the track will make the car darty and eat tires on the street.

t-von

iTrader: (8)

Good reply DamonB! So would those alignment specs given on that Pettit page need to be altered for an Fd with lowering springs?