This will probably turn into a long winded post but I have some questions to the knowledgable people out there who track there cars often.

Now, let me start off by saying I do understand that the stock suspension is well sorted. I know for a fact that I'm am considered "inexperienced" as a driver standpoint. But everyone eventually gets around to upgrading their suspension sooner or later. Better for me to start picking up information now before making any monentary commitments which I might not be happy with in the long run.

It seems that from the general consensous in the Road Racing/Autocross board, for FF/Hondas in general, that a highly rear sprung combo is the standard (i.e. F400/R500lbs). I can see how that might be preferred since there aren't as many options to get the rear rotated on a front wheel drive platform. But what I'm worried about this set up is that my driving "style" would have to change again to accommodate the change in bias. That and the fact that it might be too drastic of a change for a double duty (street and occasional track) car.

From my understanding, many people are extremely happy with a Mugen Lowdown setup and even with just Spoon Progressive springs on stock dampeners. It just seems to be a linear upgrade from the stock setup since it's slightly front biased (like the stock suspension) at the limits. But the problem with the Spoon solution is that you're still on stock dampeners on a higher spring rate. And there aren't any "good" solutions for upgrading the dampeners since Koni perchs are too low (that and the fact that nobody seems to be able to source externally adjustable rear units for rebound/compression). The Mugen solution looks very tempting but if people can "grow out" of the Spoon spring combo (which is in the same neighborhood for spring rates) rather quickly, it seems like I should pass on this too.

What I'm considering is a F8kg(~450lbs)/R8kg(~450lbs) combo with a slightly larger rear anti roll bar (23mm JDM). It's still more rear biased than stock but not so much so that it'll be like a totally different car (an assumption I'm making which could be totally wrong but please correct me if I am wrong). Also, I'm again going by assumption that it would be a streetable combo since it's only 100lbs more than a Mugen/Spoon setup.

Has anyone tried or running this type of equal spring rates in front and rear? Am I totally wrong to assume that this setup is going to be "slightly more" rear biased and it's going to be heavily rear biased? Any positive or negative comments?

It's snowing outside and I'm bored out of my wits at work.

 

With same rate front and rear, and even same sway bar front and rear, the rear stiffness is still gonna be higher because of the f/r motion ratios and geometry of the sway bars.

Spring rate is only part of the equation. Other factors to consider are ride height, track width, and LSD settings. The car can still neutral/oversteer with heavier springs up front (ie. Spoon DC2R race car).

 

its snowing outside for me too but you don't see me typing up essays
you've been hanging around anton too much...lol

btw...lowdowns for christmas for moi

 

I did a ton of homework before I purchased the Mugen Lowdown kit. First, the car is a daily driver as well as auto-x/high speed driving "schools". Second, I did not want to fool around with spring perch height, just wanted a max. of 3/4" drop (just enough not to effect camber too much, did not want to buy camber kits). Third, shock valving had to be adjustable to be able to fine tune front/rear dampening. Finally fourth, direct bolt on and good quality.

I spoke with the guys at King Motorsports and told them how I wanted the car to handle and they suggested the addition of the 26 mm rear bar. I was also going to get the thicker front bar BUT the guys at King said I would be happy with changing the rear bar only. I was very impressed they were not trying to sell me everything, just what I needed.

After years of experience of auto-xing these shocks are set at 2 front and 5 rear. With this setting you forget this is a rear oops front wheel drive car. The car rotates when provoked but the handling is like the car is on rails. This upgrade is a must but ONLY once you have mastered the stock suspension and are able to full control this car.

 

I have been extremely happy with my Lowdowns.

 

That's why I'm beginning to ask these questions now.

Ride height would be maybe half an inch lower than stock (ground clearance), track width would ultimately be some 16x7 wheel that'll clear sp00m calipers (eventually) shod with 215/45/16 Azenis and LSD would be stock as long as it doesn't break.

And don't worry Marc, I'll probably take your car for a spin as soon as you get those puppies installed.

Edit - Note, I'm not bashing the Lowdown kits in anyway, shape or form. Just needed a "kit" to make a comparison to. Oh, are Lowdowns rebuildable? Another question I've been meaning to ask.


[Modified by thk, 3:34 PM 12/5/2002]

 

Kyle you I, and Dave as well are all in the same boat, the biggest difference is that Dave is quite a bit ahead of us skill and experience wise and Is currently able to outdrive his suspension. You and I are in the middle of loving our car and learning quite a bit on how it handles and how to drive/control it.

I have asked the same questions and searched as much or more and the answer that came back to me personally was:

If you are currently happy with the cars suspension and are Not out driving it yet, then stick to your origional plan.

So, I took my own advice and took a second look at my plan and am amassing all of my next step mods which only include front and rear strut tower bars as anything relating to the suspension.

2004's season will hold my suspension upgrade.

What you Must include even if you feel a novice like myself is that We are getting more and more into this AutoX. PDA and HPDE. What Exactly do we want out of the car?

Do we want a serious competitor or just a weekend racer?
Do we want something that you Can actually drive on the road or do you want something that you need a trailer to drag it there on?

I personally am looking to build a serious competitor but, as we already know building ourselves as a competitor is the First most important thing.

Take into account how many people Actually race these cars on Stock or very close to Stock suspensions. I had investigated a bunch and thought about the Tein RE's but, am still not certain. I know I don't want to swap out any swaybars until I at least do coilovers or similar since I really like the neutrality/oversteer of the stock R's suspension. Who knows, maybe after another season, I will learn enough to make an even more educated decision next winter... I do know that I like the RG suspension that Chris/Rodney runs, and J's had a strong influence and actually suggested his spring rates. For what he does, I dig 'em pretty well. His car is more setup for Autocross but, I want a car more setup for track events...


It's still a quandry for alot of us... But, at least Wai answered. I've read a few of his postings on this subject and wonder if he promotes the Mugen lowdowns? Or other setup for You the daily/weekend guy and Me the guy building a competitive car with no holds barred but, still wanting the ability to drive it nearly confortably on the roads... Remember also that I've driven the stock R from Hartford to Miami and back... My *** was asleep most of the trip...


I know I didn't answer you Kyle, nor can I currently, I just decided to keep to my plan and my plan did not include any major suspension Anything until at least my 3rd full season and definately not until I have a strong idea more of exactly what I want.

And yes I do understand your point for posting this and not necessarily being ready for it as of right now. Thats exactly the same spot I'm in and so is Dave...


Marc is just jealous.


A.


PS C'mon Wai feed us some more suspension knowledge especially with relation to setups that will compliment each of our plans and requirements. Spring rates are wonderful but, as you said there is alot more to it than just spring rates.

 

am not

btw...wai is helping oscar alot with his suspension setup as we type


[Modified by BlueR, 4:29 PM 12/5/2002]

 

To be honest, I'm not currently 100% pleased with our stock setup. There is definitely more work needed to be done on the driver but there are certain aspects that leave me wanting a bit more. It's just something that I feel behind the wheel now that wasn't there before (or didn't notice) when I wasn't pushing as hard.

I'm fairly sure that if I do get around to doing my suspension, it would be a mid season type thing in 2003. That way, I can have quantifiable results in the form of times on the autocross course and perhaps time trials. More than likely and I am willing to make some sacrifices to comfort for something more aggressive.

Weird. I actually have more doubts and questions after going to the track than before.

 

I learned a lot about suspension tuning thru the previous debates. Some were educational but some got pretty nasty somehow.

The general idea is:
Less weight transfer at one end = More grip at that end

Total weight transfer (front + rear) is INDEPENDENT from the suspension stiffness. It is governed by the geometry of the car: Ride height and track width. With that said, a superstiff car (either end) but jacked up like a 4x4 is gonna have less grip than the same car with soft suspension and 2" off the ground.

So by lowering the front ride height and increasing the front track width (spacers), the front grip would be increased. Do the reverse to the rear and it would step out sooner. But for the front, since ride height is lowered, front spring rate has to go up to avoid running out of suspension travel; and since spacers were used, front wheel motion ratio would be retarded and spring rate has to, again, go up to compensate that.

That end up with the "JDM" setup.

The "US" setup focuses on a different theory.
The general idea is:
The stiffer end creates more (and faster) weight transfer relative to the other end. But since the TOTAL weight transfer (front + rear) has to be the same, the other end would have less weight transfer thus more grip. In other words, when having a stiffer rear than front, it sacrifices rear grip in exchange of more front grip.

Both setup can be good, as shown by the RTR and Spoon ITRs. But which one is better? It's all about your personal opinion and preference.

 

Woo. Thanks for this post. Very informative.

Now, on to the questions!

Now, what if ride height is lowered with dampeners that have an additional height adjustable collar and not from the spring perches (just using them for preload). The suspension would should have plenty of travel so no or less compensation in the form of increased spring rate would be necessary from there, correct? And again with running without spacers to increase track width.

Seems like I ended up with a quasi-hybrid setup. Gaah. Yeah, I've seen some of the down right nasty suspension "debates" and I was too afraid to jump into the fray at that point.

 

With the RealTime ITRs Pulling 1.06G's of latteral acceleration, I would consider replicating their setup, maybe in a less agressive way.

Stock the front ITR spring rate is 1.25 times as heavy as the rear. RealTimes front springs are .66 times as heavy as the rears. They also run a stiffer rear sway bar. Anyone know if the realtime cars are lowered at all?

Heres info on their setup:




.

 

I'm dying here, where's the rest of the article? lol

 

Chasis Code says DB8??

 

lol. Here ya go:
http://www.itrsport.com/reviewArticl...ltime_itr.html

 

Shock travel is one limitation. Another limitation is the physical geometry of the suspension components. For example, when the front end is lowered to a point where the upper A-arm is, let's say, only 2" away from the shock tower, then having a 4" shock travel would not mean much. In this case, the spring rate has to be high enough to restrict the front wheel bump travel to less then 2".

And because of this, the JDM shocks are short stroke, large valve diameter design so that they could still work very well even with very little shock travel.

 

good info

 

Well, I was planning to set the car at approximately 1/2" or 3/4" lower max for ground clearance issues. So with even with the lighter spring rates, hopefully, suspension travel won't be an issue.

Too bad I don't have limitless funds to try out all the different combinations available. *sigh* If I don't go out and buy suspension bits before ITR Expo 3, expect a certain FBP ITR owner to have lots of questions in person.