FWD Questions/advice

[yamaha731]

This is my first Fwd car so after last I wanted to make so changes..My front end felt great but the back of the was not following I had to really slow down. mid corner it felt like if I was aggressive at all it would swap out even at a slow to moderate the back was still loose.
I noticed the back of the car was sitting about 1" - 1 1/2" higher in the back

I lowered the back to make the car level and i pushed the rear swaybar out to the farthest out side connection points.

The car is a 1988 CRX si with skunk coilovers I think there 450lbs springs on stock struts. tires are crap all seasons( I know its a terrible setup but It's what I got)
Besides throwing money at it is there anything else I can do?

[Jeremy]

http://www.redshiftmotorsports.com/RedS ... 20Page.htm
https://www.facebook.com/HollisRacing?sk=notes

There is setup info on both of those pages.

[Jeremy]

That's crazy that they run different springs side to side.
I noticed all Civics sat funny back in the day when I had one.

To start with, here is a run-down on the setup of our car. This is *everything*, no secrets withheld.


Tub:

89 Honda Civic Si built in Canada (USDM)
Zero option (no radio, no a/c, all OE plugs and blanking plates installed)
Spare, jack, tools and cover removed
Cargo cover removed
Front lip spoiler removed
Mud flaps and rub strips removed (body colored electrical tape covers holes)
Fender lips rolled for tire clearance

Suspension:

Hyperco 6" x 2.25" springs...LF:600, RF: 550, LR:550, RR:500
Penske 8300 double adjustable reservoir shocks custom-valved by SRP (Joe Stimola)
Modified OE upper shock mounts, cut-down for weight
Energy Suspension Master Kit bushings in all positions
Prothane rear toe link bushings
Energy Suspension rear trailing arm bushings with modified OE center pin, ground round
90-91 Civic rear trailing arms (superceded part) allows ET43, 7.5" rear rims w/o spacer
SPC rear upper arm (camber kit)
Modified OE front upper control arms, slotted for camber adjustment
CRX HF front sway bar with ES urethane mounts
Custom splined rear sway bar, 1" x .095 wall x 43" tube, with adjustable arms (5-6") mounted to shock lower eye bolt. Frame mounts welded directly to OE tow hooks.

Alignment (Soulspeed Performance):

Front: .25" total toe out, 3 deg caster, -2.7 deg camber LF, -2.3 deg camber RF
Rear: 0 toe, -3.0 deg camber
Corner-weighted to even L-R front weights...total weight = 1950 lbs

Wheels/Tires:

195/50-15 Toyo R1R (shaved to 3/32nds by Treadzone), 25-26 lbs cold pressure
15x7.5 SSR Competition alloy rims, ET43

Drivetrain:

D16A6 rebuilt to OE specs. Head by Austin Cylinder Heads using all OE Honda parts. Bottom-end honed with torque plate to .010" by Performance Machine. Assembled by Andy Hollis
NGK BCPR6EY-N11 projected tip plugs, indexed and gapped to OE spec
Custom underdrive pulley (smaller, lighter than UR)
Unorthodox Racing aluminum alternator pulley
AEM cold-air intake with K&N filter
Hytech 4-2-1 header with Track Dog Miata heat shield, 2" collector
Custom tunnel exhaust with welded-in Maganaflow metal-core spun-cat (#59955), 2.25" 20 gauge stainless pipe, 2.25x4.5x22 Burns single stage muffler, t-bar clamps, turndown
Chipped 90-91 PM6 ecu board inside 89 housing, dyno-tuned using Ghettodyne software
Tranny rebuilt with new OE Honda 2nd gear set and all new bearings and synchros.
OE Honda clutch
EBay aluminum short shifter, ES bushings, CRX HF "weightless" shift linkage
8-cell X-Cell lithium battery (1.6 lbs) on cut-down and drilled battery tray

Interior:

Kirkey 10 degree Economy Layback seats (covered), custom-mounted to OE sliders, ballasted to 25 lbs.
Momo Monte Carlo steering wheel w/adapter
EBay steering wheel extension.

Brakes:

Hawk HPS front pads, rotors turned to minimum thickness
Porterfield R4S rear shoes, drums turned to maximum diameter
Gooodridge stainless brake lines

Fuel:

Tuned on 93 octane TX summer gasoline. Sunoco GT100 used for Nationals and at altitude.
5/8ths tank minimum fuel level to avoid starvation in right turns

Fluids:

20w Redline Racing oil in crankcase. Level halfway between full and low.
Redline MTL in transmission
Redline WaterWetter + plain water in radiator
ATE Super Blue brake fluid

Dry Settings:

Dry grippy concrete => rear bar full stiff
Slick asphalt => rear bar medium
Shocks => full compression all around, full rebound rear, 1/3 rebound front.

Rain setup:

Full tread Toyos on 15x7 rims, 28 psi
Raise ride heights all around by 3 turns to reduce camber and toe-out.
Rear sway bar => one position softer.
Shocks full soft.

[Jamie]

Nail down technique first. With all the weight up front, the car's balanced to understeer naturally. It's very easy to overdrive it, plow into the corner, lift off and have the back end come around. If you work on it, you can make that work for you deliberately.

Stock shocks are woefully inadequate for 450# springs. You'll have to replace them sooner or later.

If you still have the front bar, trying removing it -- that's a pretty common trick for Civics/CRXs. You can also play with differential tire pressures -- set the fronts, then run the rears either much (15-20 psi) higher or lower. My Prelude always responded better to a high front/low rear setup, but different cars respond differently -- try both ways and see what works.

And yes, Andy Hollis has forgotten more about setting up '80s Civics and CRXs than any of us will ever know.

[Loren]

Put tires on it first. Anything you do before that is just throwing darts.

You actually WANT to set up a FWD autocross car to oversteer... it's the only way to (almost) cure the understeer!

You need to put some decent tires under it and just figure out how to drive it. Remember, when you're on the throttle, you're shifting weight to the rear to help the rear stick. In a FWD car that's set up to give you maximum front grip to accelerate out of a turn, that means that once you've committed to the turn, you DON'T LIFT. If you lift, you spin... or at least have to fight a slide.

As with any lowered car, be sure you have bump stops, and that you're not hammering them on one end or the other too hard too early in a turn. With the back that high and on 450# springs, you probably weren't hitting the stops in the rear. It's just something to keep in mind. I had a friend who was a mechanical engineer for Boeing who drove a CRX. Modded the hell out of it, calculated freakin' EVERYTHING, as engineers do, and on paper... he had an ideal suspension. Never could get the car to handle consistently, though. One day he had the car up on jackstands and realized that he had been riding around with the coilovers set so low that he was always HARD on the bumpstops. He raised the car an inch and solved all of his problems!

As I recall, CRX's have a good front suspension design that can actually gain some negative camber in a turn, unlike most McPherson Strut cars. So, allowing the front to have some compliance (and not be locked down with super stiff springs, bars and shocks) can be a good thing. The rear is where you want to have some good adjustable roll stiffness to play with.

FWD is all about managing understeer. Getting one set up to oversteer is actually a good thing to some degree. It can be excessive, but you really can't judge that with crappy tires and RWD driving habits.

How to drive it? Especially with crappy tires, don't dive into a turn too hot. Slow in, fast out. Be patient with the throttle, applying just enough as you pass the apex, and adding more as you unwind the wheel. (and one FWD trick is to modify your line so that you can start unwinding and getting on the gas earlier... you CAN'T accelerate and significantly turn at the same time with FWD) The goal is to never overpower the front tires.

If the car is set up right, it's going to want to oversteer anytime you're turning and off-throttle. Keep that in mind, as well. It means you need to brake EARLIER, and be on the gas (slightly more than neutral) as you enter the turn. (you can play with that on tight turns and learn to let the back end drift out and catch it with throttle... jam on the throttle, weight shifts, slide stops!) And then you add more throttle as you accelerate through the turn... and NEVER LIFT IN A TURN.

The hard part is learning how to slalom with a car that's set up that way. My first autocross car was a Saturn. I had the car set up perfectly, it was very fast, and did things that made people say "I didn't think you could do that in a FWD car", like a controlled 4-wheel drift in a sweeper. But, if I put an unfamiliar driver in it and there was a slalom on the course, they would invariably snap-spin the car before the second slalom cone!

So, what I'm saying is... there's a learning curve. Your setup might not be perfect, sure... but there's a learning curve. And you don't have to spend money on the car to start going up that curve.

[yamaha731]

I guess I just have to learn to drive it until I have money for tires. Thanks I appreciate the help

[Loren]

Probably the biggest thing to keep in mind, since you're more familiar with driving high-powered RWD cars, is that if the back end starts to slide in your FWD car, you pretty much do the opposite of what you'd do in a RWD car. Even in a RWD car, you wouldn't want to abruptly lift and induce a spin... but you might lift a LITTLE, especially if it was throttle-induced oversteer. In a FWD car, if the back end steps out, the answer is ALWAYS more throttle. Usually all of it. Put the weight rearward where you need it.

[yamaha731]

I know I was lifting when the back end would loose traction. It's gonna be a learning process hopefully will get a few more runs next time.

[garage west]

As I recall, CRX's have a good front suspension design that can actually gain some negative camber in a turn, unlike most McPherson Strut cars. So, allowing the front to have some compliance (and not be locked down with super stiff springs, bars and shocks) can be a good thing. The rear is where you want to have some good adjustable roll stiffness to play with.

Honda called it "twin independent double wishbone suspension" (control arms front and rear). These cars can be setup.

[aw614]

I know I was lifting when the back end would loose traction. It's gonna be a learning process hopefully will get a few more runs next time.

Im not sure what the next fast event I'll be able to attend since I've doing the corvette event on oct 4th and two events on a weekend wears me out, but if you want to try to drive my integra at a classic event with pretty much the same suspension as your CRX you are welcome too for comparisons, I think Im at the point where I am all caught up on all the maintenance on it, new bushings, shocks, etc. I installed Type R springs so I think I'll be switching to M3 based on the classing rules.

Just let me know.

Everything I've read about properly setup EFs and CRXs compared to the newer cars when properly setup, seems slightly different to the later generation civic/integras with how they seem to rotate a lot more effortlessly even without large sway bars, and the back following the front. Andy Hollis's page is a good resource like mentioned and if you search older threads on Hondatech, there is a lot of good discussion information on the chassis.

I wonder how much longer your shocks will handle that spring rate, they could be contributing to the back end losing traction, does it feel sloppy and snappy when the back end comes out vs being able to control it? I have a set of rear 88 crx/itr koni yellows if you have the eyelet control arms if you are interested, I dont have the fronts, but Im willing to let them go cheap since its missing some of the parts.

For brooksville I've been running like 40 psi front, 43 psi rear with RE-11As, probably not ideal, but my tires are pinched. But I've found to drive it fast it has to be loose, it doesn't feel right to me still, but I seem to be a lot faster.

[aw614]

Chris,

Have you tried driving without the rear sway bar on your crx? It seems some people run without the rear on a CRX and still get good rotation due to the short wheelbase with stiff springs already which you already have. One guy at the autox last week was rear sway bar less on his crx and he was still getting good rotation, sometimes spinning it out if he wasn't careful.

[yamaha731]

Chris,

Have you tried driving without the rear sway bar on your crx? It seems some people run without the rear on a CRX and still get good rotation due to the short wheelbase with stiff springs already which you already have. One guy at the autox last week was rear sway bar less on his crx and he was still getting good rotation, sometimes spinning it out if he wasn't careful.

The car feel's pretty good right now. I think once I get some new shoes and tighten a few loose bolts I'm going to be happy with it.

[Loren]

Your engine mount bolt and spacer are still rolling around in the floor of my car.