Setting up suspension... On-going thread...

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ZedEx
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Setting up suspension... On-going thread...

Post by ZedEx »

Well, as far as suspension goes, mine was pretty basic. D2 coilovers with D2 lower contorl arms (Not that those make a damn bit of difference). However, after speaking with a friend on the matter, I've decided it would be a very worth while investment, to properly dial in the suspension.

Researching it, speaking with D2, and figuring out the best way to go about it, I discovered my stock spring rates on the D2 kit I have, is 9.8kg/mm (548.8lb/in) front, and 6.2kg/mm (347.2lb/in) rear... Yeah, understeer much? The car's been through a couple DE events, and it's done more than fine, but the understeer is just ungodly bad.

So, the solution? Here's what I've come up with speaking with people who know more than I do:

- Full-Race traction bars
- 12kg/mm springs in the rear (See how the 10/12 split does on the car, might need to go 12/14)
- Spherical rear trailing arm bushings
- JDM 23mm rear sway bar
- Supa' secret arignment

So, I ordered 12.1kg/mm (677.6lb/in) rear springs for the car, installed them, and WOW... What a huge difference. The car drives completely different already, I'm utterly shocked at how well it handles with just that change. I guess looking at it on paper, the rear rate is effectively twice what it was.

Today I ordered my Full-Race traction bars, and I'm hunting for a JDM 23mm rear sway bar to snag up. I'm excited about getting the car ready in time for December 1st for full course VIR, I can't wait to see the difference between this setup, and the old setup. I imagine I'll have to exersize some more finesse in the uphill S turns, but other than that, not too terribly much should change... Maybe Roller Coaster, we'll see.

I've also decided to spend the money on some wider wheels for track usage. I'm thinking some 15x7 +42mm offset Buddy Club SF-Challenges would be nice. Generally lightweight, nice looking, and most of all, CHEAP. Along with increasing wheel size, jumping up to a 225/45/15 tire will greatly help. I'm thinking Nitto NT-01 would be the best bang-for-the-buck. Although this is an important step, it's a step that will take a few weeks/month or two to get to... The wheels alone are cheap, but the tires are going to be expensive, and will not last all that long on track.

Another modification to consider if needed, would be moving to an LS 19mm front sway bar. Although it would help a more experienced driver, I don't believe I'm to a level that it would be at all advantageous for me at this point. However, I need to see how this new setup does, and it may be something I move to a bit later down the line after I've learned to extract all potential from the new setup.

Anyway, this will basically be an on-going thread pertaining to setting up my suspension, seeing what floats, and what sinks. Pictures and results will come as they develope.

If anyone has any suggestions from experience, I'M ALL FOR IT.
National Speed INC.

-2000 Acura Integra Type-R - PY #686 - Track/Street WhoRe
-1997 Honda Prelude Type-SH - Daily Driver
walker111
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Re: Setting up suspension... On-going thread...

Post by walker111 »

I would say that jdm 23mm sway and spherical rear trailing arms are not needed. Traction bars are only gonna "tighten" things up in the front a little by tieing the core support and the lca's together. If I were to do it again I would've done bushings first, then suspension. My 10 year old bushings had quite a bit of wear to them.
98 CW ITR 322
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Re: Setting up suspension... On-going thread...

Post by 98 CW ITR 322 »

walker111 wrote:I would say that jdm 23mm sway and spherical rear trailing arms are not needed. Traction bars are only gonna "tighten" things up in the front a little by tieing the core support and the lca's together. If I were to do it again I would've done bushings first, then suspension. My 10 year old bushings had quite a bit of wear to them.
I concur. These ARRHHs are getting old and new bushings would def. tighten things up.
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get RIGHT
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Re: Setting up suspension... On-going thread...

Post by get RIGHT »

Its amazing what a stiff rear can do, eh?

Having upgrading all my bushing in the front of the car. I agree with the peanut gallery. Huge diff.

I personally wouldnt do a "supa secret" allignment if you plan on rolling the car on the street. Just use sway bar, shock settings, staggered wheels, and/or tire pressures to get there.

I personally dont recommend 225s for you just yet. Stick with 205s for at least one more set. You still could use the seat of the pants feel of the smaller wheel. The wider wheel is gonna do a better job of masking your mistakes and you dont need that just yet.

My .02.
Erik95LS
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Re: Setting up suspension... On-going thread...

Post by Erik95LS »

get RIGHT wrote:
I personally wouldnt do a "supa secret" allignment if you plan on rolling the car on the street. Just use sway bar, shock settings, staggered wheels, and/or tire pressures to get there.
Yeah, I would just go with a semi secret alignment for a street car. :P

I'd also say just wait on most of that. Making a bunch of changes at once often tends to make things worse and harder to figure out what is doing what and hard to decide where to go from there. I'd suggest trying the bushings if you really want to do something, but don't bother with the sphericals just yet. Your car will rotate very very well with your now current spring rates and a mildly secret alignment.
-Erik

"i sneezed and jam came out" - R-Box
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