Rotors R Cool

I'm trying to work out a massive understeer issue. The previous owner apparently decided that for some reason, he would put on a 32mm solid front sway and leave the rear stock. On top of that the car is running on 255 front and 285 rear. Sometimes I have so much rear grip that I can stab the throttle and all 330rwhp can't break the tires loose. (Although through trial and serious error a clutch kick does the trick )

Simple question.... Who has the Racing Beat front and rear kit and how do you feel about it? I am willing to go all out and get the best of the best as far as adjustability goes but who makes both adjustable front and rear?

I got out cornered by a factory 05 350Z. I will do whatever is necessary to fix this thing.

Howard Coleman

iTrader: (6)

you have a number of issues at play.

first off i recommend 255 fr and 285 rear so your tire sizing is excellent. the front bar is a primary problem. you do not mention your springs and shocks. pls specify what you have.

as far as sway bar options... you have some. it does depend on what you are trying to accomplish. do you track your car?

i consider Tri Point's adoption of the Speedway Engineering hollow adj front bar combined w WideFoot mounts to be the best setup. it works well w the OEM rear bar.

don't neglect setup. pls read at a minimum my first post in the thread entitled "Howard Coleman's FD chassis/suspension setup" in this section of the forum. if you cursor thru the thread you will find all the details re the swaybar.

set your car up as per my suggestions and you will never again be outcornered by anything on it from Nissan.

good luck,

hc

muibubbles

iTrader: (36)

hahah i love this quote for some reason! HC is always a good source for suspension questions, like he said read that thread... great info!

Rotors R Cool

It currently has Tokico Illumina's and I believe Eibach springs of unknown lbs/in. The whole suspension has been done by the previous owner who primarily drag raced the car. I have been trying to slowly get the car in circuit racing condition and I just got to the handling part. Found a nice flat and smooth underpass u-turn and used it to slowly push the car to the limit to get an idea of the balance. It only took 2 passes to realize that the car is unbearable.

I have thought about going with a new coilover setup and was looking at Tein's Super Race. Then I saw the 783lbs/in springs in all 4 corners and started worrying about streetability.

Howard, you suggest an adjustable front bar only, and not to argue with your advice but I would have expected to need both bars replaced. Any reason why this isn't the case?

On another note, a friend of mine told me that you sent him a chart of different alignment settings based on wheel diameter and tire width... Could I get a copy of that if you have it laying around? And, can you please point me in the direction of a good source of suspension info like a book or something because I'm having a little bit of a hard time understanding how every part of the suspension system can affect handling. I'd like to learn.

Thanks,

xcannibalx

Yo,
I'm not Howard, but i can tell you I learned a TON by reading this thread through
https://www.rx7club.com/suspension-wheels-tires-brakes-20/howard-colemans-fd-chassis-setup-723617/

The first post is VERY informative. From what i understand, the eibachs and tokico's are a great combination. I wouldn't bother changing that out for coilovers...You'd just be spending money for a very minor increase in performance, if any.

habu2

+1

read Howard's thread, after studying it I bought Tein SS w/extra 8/6 springs, Tanabe swaybars and the RP rear traction kit (links & diff bushings)

if the wx holds I hope to install all over the holiday break.

Howard Coleman

iTrader: (6)

Eibach made only one 4 spring setup for the FD. your springs should have a 5525 PN on each.

if they are Eibachs they are an excellent start for you.

setup is everything. read the first post in my thread for complete setup instructions.

lose the front bar. unless you want to spend $500 for the TriPoint front bar and another 2-300 on widefoot mounts buy the Tanabe front bar. on any uprated front bar the bar mount needs to be upgraded. there are a number of options Widefoot being the best but not the only fix. you may already have an uprated mount given the size of your current bar. if not look for cracks.

do not draw any conclusions re your handling until you have had your car aligned to my specs.

i know of no single book, though i am sure there are some, detailing suspension dynamics, i have read most but learned what i know from 22 seasons of serious racing. most of what you need is in my thread.

good luck,

howard

Rotors R Cool

Thanks a lot for the advice.

I just thought of something though. I was thinking about why a drag racer would even throw a sway bar on the car. And I do have a little amount of evidence of wheel rub on the front wheel wells. Is it possible that with a softer sway is the front, it might start rubbing the top of the wheel well?

But just to make sure that I have your advice correct, you want me to first reset my alignment and then if it continues to under-steer, I should spring for a different front sway and leave the rear stock.

BTW I don't know much about setting caster on the alignment rack, so when you say "Caster equal minimal" what does that mean as far as numbers?

Thanks,

xcannibalx

What this is refering to, is to set both left and right wheels "equal" in value. I believe if you read through that thread, 5 degrees is about right for the "minimal" 6 seems about right where you want it . It's super important that each side is as close in value to the other.

habu2

I didn't mention it but I also bought the Widefoot mounts for the Tanabe front bar.

I'm also considering these adjustable front bar end links:

http://www.improvedracing.com/produc...products_id=29

I found the Carroll Smith books to be very good, although it has been years since I really read them.

No book can replace seat time but they do give you an understanding of what is going on and why, making your seat time much more productive.

Rotors R Cool

Thought I should come back here and right a conclusion to my journey, or rather an update. I have to admit now that I severely neglected a few parts on the car. I got the car from the previous owner almost 2 years ago and never bothered to check the alignment. Further neglect to check the tires kept me from considering the alignment as an issue.

I took a quick look under the front of the car and saw a HUGE blue sway bar. I thought, "Cool he already put on a pair of bars". Looked under the rear and didn't see any odd colored parts. I thought, "WTF, that guy is an idiot..."

That brings us to my original post. Howard advised me to setup the alignment to his specs before changing parts, so I did.

I took the car to a friends job and threw it on the rack. We checked the alignment and I immediately smacked myself in the face.
Left Front: 1/2 inch toe out...............Right Front: 3/4 inch toe out
.................-.2 degrees camber..............................-.2 degrees camber
.................+6.1 caster.........................................+6. 2 caster
Left Rear: 1/4 inch toe in...................Right Rear: 1/4 inch toe out
................-.4 degrees camber..............................-.3 degrees camber

For the first time the car was in a position for me to walk under it. This is when 2 more things just sucker punched me in the throat.

First, the tires are toast, serious toast. Both the inside lines of the front tires are bald while the outside lines have about 5/32 of an inch on them. The left rear is bald in the center and the right rear is just like the fronts.

Second, while walking under the rear, I look up and see a hint of blue. Interested as I was, I looked closer. It's a blue freakin sway bar, all the way up there.

Now the alignment is set to Howard Coleman's specs with me sitting in the car. Interestingly, when I step out of the car the right side alignment changes to -.8 degrees of camber and the rear thrust angle points left, everything else remains the same.

Now the car performs very well with a few small glitches probably stemming from the totally F'ed tires (I'm low on money so I'm running them for all they are worth). Mostly just an issue of low speed understeer, during speeds below 20. Which I think is supposed to be normal. Also I still have a problem with understeer while braking and while engine braking but not during steady state cornering or accelerating.