my civic weights 2275 lbs with me in it. 560 lbs/" springs all the way around, kyb agx set to 3 front 4 rear. 24 mm eibach front bar 19 mm rear neuspeed bar. handling is perfectly neutral off the throttle, it's actually pretty hard to get the rear to step unless do you give it really abrupt input. i would like more rotation but don't really want to stiffen up the rear more at this time. i've been running zero toe front and back. 3 deg camber up front (i'm satisfied with tire wear except from no LSD; tire wear is fine from cornering and pyro reading is good) with 2 deg on back. rear tire gets way less temp than front, and visually the outside shoulder of rear tires isn't being used much. i'm thinking of reducing the camber to 1.5 deg... that should give slightly rear tire wear from less camber and might just reduce the rear grip enough to give me that extra rotation i want during turn in.

just thinking out loud.

ps, recently turn a low 2:14 at thunderhill full track on a warm 90F+ day. about 3 sec. off ITA qualifying/race record... i think with LSD, better weather/track conditions and if i do T1 with out braking i ought to match the record pace. car sustained 1.2g through out T2 the long constant radius sweeper.

 

Washer trick.

 

more grip up front can be attained for almost no cost....

more caster ( swap UCA's)
1/8" toe out TOTAL , still within OEM specs FYI

and kill some camber , that should help with the rotation problem

 

will toe out actually increase front grip or just changes the way it feels?

 

Your front springs are too heavy and rears possibly too soft (slightly). Might also consider eliminating the front bar all together. More toe-out in front (as suggested) but would keep the rear camber as is. Also could try slightly higher rear tire pressure.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GhettoRacer &raquo;</TD></TR><TR><TD CLASS="quote">will toe out actually increase front grip or just changes the way it feels?

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you will notice the effects , no doubt about it.

I have no data as far as laptimes to back up this , I simply know the large difference in the amount of grip i gained up front after I tracked the car with the new alignment.

 

I'm pretty sure the ITA race record at TH is low 2:09 if not lower. I know Nick turned a 2:09.3 in 01 season, which at the time was the record. Just thought you'd like to know...

 

I think there are a number of things that you can play with to alter your overall balance but I would not change the camber to do it.

Use a pyrometer and check your real cross tire temps and that will tell you exactly where your camber and air should be. Wear is okay but not nearly as exact to measure with as temp. Certainly the fronts will get hotter because they will be doing more work on the car but the rear temps are important to judge what the rear tires are doing. The tire's job is to interface the car to the ground so a "happy tire" is you main goal and use the other parts to make your driver and lap times happy. Don't sacrifice function potential to effect balance of the car when there are better tools for that- sort of letting the tail wag the dog.

I tend to agree with 1/8 total toe out on the front as your turn-in and feel should improve although rear toe at zero unless it is a very slow speed, tight course. For the balance and rotation issues, I'd consider looking at springs and your front sway bar size but the single first thing I'd do is start checking tire temps regularly and get them optimized. You may find that they are already compromised to get the handling that you already have.

To me taking a step back and looking at the overall picture, your springs, bars and alignment would hint at a understeering or at least nose focussed car before we add driver inputs into it (cognitive or not actions to toss the car or make it be more neutral).

Do the tire pyro thing regularly as it will give hard numbers with how the car interacts with the ground. Without them working to their potential, you are just moving around in circles hoping to come up with something good.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by CRX Lee &raquo;</TD></TR><TR><TD CLASS="quote">To me taking a step back and looking at the overall picture, your springs, bars and alignment would hint at a understeering or at least nose focussed car </TD></TR></TABLE>

I'd shitcan the big front bar also , the civic front bar is more than ample IMHO.

 

Or increase the rear bar...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Eee Pee &raquo;</TD></TR><TR><TD CLASS="quote">Or increase the rear bar...

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or both

a stock front bar can be had for very little , thus the reason I said that first.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Doctor CorteZ &raquo;</TD></TR><TR><TD CLASS="quote">

I'd shitcan the big front bar also , the civic front bar is more than ample IMHO.</TD></TR></TABLE>

I 2nd that. Get the EX/Si 21mm bar. I would not remove the front bar completely as the car won't transition well.

As Lee mentioned, the car is set up to understeer @ the limit.

I assume that you have already swapped the front upper arms. This will change the caster & help with turn in.

I don't think that I would change the rear camber setting. It would seem to me that you will be riding on the outside shoulder with that low a setting.

Just for reference, is that time with the bypass or the 'nest'?

 

do you recommend probes or infrared type?

it's just a daily driven street car... i also haven't really done much tuning on the car. just been getting seat time mostly and working on the driving. but now it's time for some suspension tuning.

speaking of pyro... i don't usually do it, and only check it once in a while when someone brings theirs out. i usually set the pressure simply by looking at tire wear and feel what the car is doing. i'm usually with 1-2 psi of optimal (if you look at the tire temp strictly). after we fine tune the pressure and set it "perfectly" according to pyro, i find the lap times and the feel showing no notable difference. thus i usually don't bother with pyro... i guess since i'm a 1 man crew usually i don't bother since it's PITA to get good temp (coming in at a hot lap and measure). i'm sure there is a small edge to be had from it but for just hot lapping fun i value seat time more currently... but i should start logging setup data on track days. where is my crew chief??

speaking of front bar removal. on the Hasport EP3 I ran during that Super2NR Honda vs. Nissan Club battle, for one run we disconnected the front bar. Neither the lap times or seat of pants changed much. The car still had considerable push. I was trying to get Hasport to remove the RA1 tires on the back and put in street tires on... but they felt it was too aggressive.

 

I second the move to a little toe-out up front.... 1/8" total toe out.

-2 seems a bit much for the rear camber. I prefer between -0.5 and -1.0. These are cheap (free) changes. I would try one or the other first and see what you think.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GhettoRacer &raquo;</TD></TR><TR><TD CLASS="quote">
speaking of front bar removal. on the Hasport EP3 I ran during that Super2NR Honda vs. Nissan Club battle, for one run we disconnected the front bar. Neither the lap times or seat of pants changed much. The car still had considerable push. I was trying to get Hasport to remove the RA1 tires on the back and put in street tires on... but they felt it was too aggressive.
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EP3 is a totally different animal. If I remember their suspension setup, they had springrates, camber and rideheight well off of what a DC5/EP3 needs to corner well and not push. Removing a front swaybar on that car wouldn't have done too much to help anything.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GhettoRacer &raquo;</TD></TR><TR><TD CLASS="quote">do you recommend probes or infrared type?
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For DOT tires, a probe style is typically recommended as the carcass and trewad depth is thicker and you want to get a reading from as deep as possible (don't poke holes in your tires though). The Infrared have some good uses and are fast but measure only the surface itself. The real heat in a DOT tire is a bit below the surface and as you come off the track the very surface is what cools first so the infrared is more affected by natural cooling. I have seen some tire companies use infrareds if they have to gather data from a lot of people but generally they use probes. I have done my own temps ifIi had to, just keep your pyro, pen and paper in the glovebox. Always do the same pattern on the car and usually going to the hottest tires first so even if it takes a few minutes to unbelt and get your readings, you will still have them and you have an established pattern. When I pull in at the end of each session, when I come to a stop I habitially cut the front wheels hard to the right (or left) just so it is easier to get to the outer, middle and inner tread areas.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Ausmith &raquo;</TD></TR><TR><TD CLASS="quote">-2 seems a bit much for the rear camber. I prefer between -0.5 and -1.0.
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Not if he is running the RA-1. You will need @ least -2* to optimize the tire. If you aren't getting good visual indication of wear @ your current settings I would theorize that is because the front is sliding so much tha you aren't close to the rear tires potential.

On the track, as long as you can control it, the faster the car rotates, the faster you can get the drive wheels straight & back on the gas.

Of course, you will be making some comprimises as you stated that this is a street car too.

 

sounds like you should try some tire stagger.

ok guys, now knock that theory down again.

i dialed back from -2.7* to about -2.3* on street tires and the car was better. not by a huge margin, but better none the less.

you're front travel limited to begin with. (especially with those damn kyb's in there) softening your front springs or front swaybar will almost defininately make things worse. do the math to verify this for yourself.

some food for thought though. my car is using a 24mm front bar and 700lb front springs. with 1.5" of bump travel (the last .25" is on the very soft initial portion of my bumpstops) and only pulling .9g's i have roughly .5" (counting that last .25" that's essentially bump stop) of bump travel available at terminal roll. if a tacked on another .3 g's, i'd be on the soft portion of the bump stop for sure. hit a bump now and i'm fawked.

another idea. you are saying you are suffering from corner entry understeer. grab a set of koni's for your car and see what happens. those kyb's have too much compression damping imo and could be contributing to your problem. ie, corner entry understeer carries through to the next phase of the corner.

nate-who doesn't like the blanket "remove the front swaybar" statement.

 

Nate,
What are you using on the rear? Are taking into account his complete package?

I can't argue about the math. Frankly, I don't have the intelligence or the patience to do the equation. I do feel I have a bit of knowledge about what works by using my car. Frank & I have the same chassis. The advice that I have given him would allow his car to rotate more.

You have introduced a valid point where suspension travel is concerned. Perhaps he is bottoming out @ the limit. That would transalate to push midturn to exit most likely. He said that he is pushing on begining of the turn. Less bar &/or more toe out in the front would limit the slip angle on the outside front. This should lessen the push on corner entry. Another thing that could be happening is that Frank could just be going in way too hot - I don't think this is happening but it could be. Even good drivers can develop bad habits.

 

Don't screw up one end of the car to fix a problem at the other end. If the problem is understeer on entry and is OK on steady state and exit, I would vote for shocks. The KYB's do have a lot of compression damping and are light on rebound. That would tend to overload the outside front tire on entry, then become OK once the stead state is reached. Does it tend to understeer in quick transitions too?

 

that time is with the nest/cyclone. getting a LSD is on high priority as i'm sure i can gain at least 1 sec from being able to get better speed out of T2-T3-T4, better exit out of T11/12, T14-15. the times were also on full thread RA1 so perhaps as it wears down i will gain slight corner speed. i'm confident with some small changes the car can match the ITA record pace of 2:11.

the car does not push. it is actually completely neutral off throttle. the car setup isn't ultra aggressive like a fast FWD should be.

ohh btw, i installed one of those A-Sport chassis brace. it actually helps a lot.




Modified by GhettoRacer at 12:18 AM 8/4/2003

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GhettoRacer &raquo;</TD></TR><TR><TD CLASS="quote">ohh btw, i installed one of those A-Sport chassis brace. it actually helps a lot.
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elaborate please.

I'm not up on my barZ

 

yep, took into account the whole package. last year i was severely travel limited. a ran 600f/500r. because of the travel issue, going from a stock front bar to an itr front bar _improved_ corner entry, _improved_ mid-corner rotation, and _improved_ corner exit. my car wasn't that low either, the 5th gen's just have that little suspension travel. the ra-1's are going to increase the cornering loads and increase the lateral weight transfer. all the more reason to assure that the car isn't running on the bumpstops. if it isn't (i don't see how it couldn't be) then start playing with a smaller front bar. for now though, i would try a bigger rear bar, a smaller rear tire, less rear camber, more/less rear tire pressure, (depending on if you like high rear pressures or low) or more rear toe out. and in that order. if some slightly stiffer rear springs were acceptable, i'd do those right after trying the bigger rear bar.

frank, the car should be neutral on throttle and nearly ungodly loose off throttle, but i'm sure you know that. my car now is so loose off throttle or under braking that i have to work to keep it straight. still not quite enough on throttle rotation though. unfortunately a 195/60/14 falken, though it is 3/4" narrower then a 205, has a different sidewall construction that makes a 205/195 combo on my car scary in transitions. i also can't go to a bigger rear bar for fear of destroying my rear subframe. i'm leary of going even higher with the rear spring, so the only thing i'm left with is toe, camber, and pressures. i'm in the process of gradually reducing rear camber right now since anything over 1/16" rear toe out is only driveable for mark daddio. i'm finally down below 60psi in the rear tires and the car is only getting easier to drive.

andy has a good point. if you are looking for corner entry rotation, look to shocks first. some koni's and gc upper strut mounts would make a world of difference. better damping and more travel.

nate

ps. this is a 93 si right? aren't they still in ITS?

 

Ghetto Racer, why do you even care what the ITA record is? that's like me taking my CSP RX-7 and comparing my times to a GS CRX....

Dan

 

Nate,
I agree with some of your suggestions & disagree with others.

First, I too have dealt with the limited travel issue. I also had a setup with so much rotation that Taz Harvey thought I had a low rears when he drove it.

Stiffer rear springs would definitely help assuming the shocks could handle them. The AGX's really can't. He also stated that he didn't want to change rear springs @ this time.

The front bar I suggested is the EX/Si/GSR bar which is 21mm. The ITR bar is 22mm, IIRC. I didn't suggest the wimpy DX bar. I am running the same front springs as you without any bottoming problems.

A bigger rear bar would definitely help.

While it seems pretty common for auto-x & is used by the JDM guys, I don't like using a smaller rear tire.

He could use less rear camber. That will get him his rotation. IMHO, he won't be optimizing the tire or the complete package by taking that route.

Adjusting the tire to adjust the slip angle is something he can do. I have used the pyro (probe style) & wear to try to optimize the tire & adjusted my suspension from there. Holy cow - 60 psi! RA-1's (or pretty much any tire) run @ that pressure would be nothing but an overheated, greasy mess after a warm up lap or two @ Thunderhill.

I prefer my rear toe @ 0*. I feel the car gets too loose with toe out......which leads to fact that everyone has something that works for them.
Their point of reference differs because of how they like their car to handle & weather or not it is used for the street/auto-x/road course. Good to see all the opinions since we can learn from each other.