What do I upgrade on my CRX?
Posted by Mad Scientist on January 4, 2008
If you’re here, you’re a CRX enthusiast. You’ve probably changed some parts on your car, which could be anything from mud flaps to engine swaps. You’re excited to do something… anything, really. You want instant satisfaction when the job is done, and you want to be able to show it off. Most tuners start with i/h/e (intake/header/exhaust) as the first mods because they’re often the best bang for the buck, horsepower-wise. I’d like to take a moment to explain why this is an incorrect approach.
The little engine that could (and still does)
When driving a car, the engine has surprisingly little to do with the experience. The difference between driving an HF and an Si has very little to do with the engine difference, as anyone who swaps a d16a6 into an HF will confirm. Going from a 18-second quarter mile to a 16-second quarter mile is admittedly unimpressive. You feel accomplished, and believe that it’s a completely new experience. If someone who has never driven a CRX gets into the car, they’ll say that it feels peppy and handles well, but really won’t say it’s powerful. Tuning your motor is a great hobby, but the CRX isn’t known for its engine and never will be, no matter what engine you use.
If you are set on tuning your engine, i/h/e followed by a cam and a pgmfi tuning is the best financial way to create NA power (because of smog restrictions in many states, NA power is preferred).
(edit: this changes considerably with my CRX2.0 project)
Teaching an old dog old tricks
Instead, focus on improving the strengths you already have. Going from “decent handling” to “rides on rails” is a relatively cheap upgrade. It’s also the difference between a stock CRX and a race-prepped CRX. Racecar drivers focus on suspension, not engine power. Even on the drag strip, a powerful motor is nothing without a well-tuned (stiff is not necessarily tuned) suspension to back it up. Take my word for it, a d16a6 is a perfectly fine engine for a CRX, especially with light tuning.
How to enjoy the twisties
Starting from square one, you really should update to a d16a6, and get some decent tires under you. Personally, I’m a fan of BfGoodrich G-force sports. They’re inexpensive and last a decent number of miles, and the traction is excellent for the price. Depending on your tastes, 14″ to 16″ rims are the only reasonable rim diameters. Larger rims are useful because they have clearance for larger brake rotors (which aren’t always an upgrade in performance) and your tires can be lower profile (better road contact) without changing your final gear ratio. To offer my personal preference again, I use 16″ diameter by 7.5″ width rims with 205-45/16 tires.
How to survive enjoying the twisties
After you have contact with the road, you’ll want to maximize it. A full coilover suspension kit is often the best choice, but if you’re working on a budget a well matched set of springs and shocks are an excellent substitute. Do research on what is the most effective, bumpy roads won’t allow for severe lowering (over 2″ is severe). I’m a fan of H&R Sport springs and KYB AGX shocks, as they’re well-matched and inexpensive. There are several other combinations that will work wonderfully as well, so don’t just take my word for it. My choices are just examples, do research for yourself. Whatever you end up doing, don’t install springs without struts and a camber kit (when necessary). Always get your car aligned after suspension modifications, and don’t over-lower your car!
Exiting the twisties (and slowing yourself down)
Brakes are the next logical step, but there are a few myths that I should mention. Bigger rotors are a negligible increase in braking power. They decrease your acceleration and are more expensive to replace. Larger rotors (such as Integra ~10″ rotors for the front) simply increase heat dissipation. A much more worthwhile upgrade is stainless steel line ends, high-performance (NOT RACE) brake pads, and if you’re feeling especially adventurous, a larger master cylinder. These will increase your brake response, and make a very noticable improvement. Rear drums are perfectly fine (if not preferred) for a CRX because they’re lighter and require maintenance much less often. Disc brakes are easier to maintain but require work much more often. Check out Drilled, Slotted or Blanked? for more stopping info.
Coulda, Shoulda, Woulda
Lastly, to maximize the power that your engine is putting out, a light port and polish combined with a performance clutch and an intake/header/exhaust (stay TASTEFUL, please!) will give you the satisfaction you’re looking for and give a good feeling as to what you’re doing. At this point, you’ll have a good idea as to what you want to doing for serious modifications and your options are vast. I highly suggest visiting the great community over at d-series.org for more info and suggestions. Suspension can be stiffened with bushings and strut/stabilizer bars, brakes can be upgraded with lightweight rotors and multiple-piston calipers, the engine can be upgraded with a swap, turbocharger, or ecu tuning (this is the most essential part, don’t forget it!), you can add a body kit or JDM body panels for visual appeal, or you can continue to drive your quick and efficient car around as a commuter or weekend warrior racecar.
Theories to draw from
In closing, let me point out that the most competitive races on the planet are 600cc motorcycle races. The most powerful motorcycles are seldom the winners, and the best riders depend on bikes that “feel” the best. That’s exactly where your focus should be. Always assume that you (as the driver) are the weakest link in the car’s performance, and improving your connection to the car will yield the greatest results. 700hp is useless if you can’t utilize all of it.
March 4, 2008 at 5:42 pm
Thanks for the good advice. I don’t know where you are from, but can you recommend a good shop in the Los Angeles area for performing light suspension and brake mods, such as the ones you suggest?
TIA.
stp
March 4, 2008 at 7:05 pm
Well, I’m in the SF Bay area, and have garage space, so if you want to make a (somewhat long) trek up here for a weekend or something, we can get whatever mods in that we have time for and you can be back on your way. I don’t generally use shops, myself. I use service manuals and buy tools instead of taking a car to a shop. Not that there’s a problem with trusting your car in someone else’s hands, but that’s just how it works with me.
Let me know if you’re interested in visiting, I may be attending a SO-CAL meet sometime within the next few months.
Glad to hear that you’re enjoying the articles!
March 20, 2008 at 5:02 pm
Hi Jesse,
I didn’t see that you had replied to this previously. Sorry for the late response. I don’t get up to S.F. very often but thanks for the kind offer anyway. I wish there were more mildly modified CRX’s around so I could see what combination of stuff would appeal to me. I’m reading a book on suspension modifications in general, but it gets pretty deep pretty quick. What I DON’T want to do is get a bunch of upgrades that DON’T work together well and end up with a car that handles worse than stock. What I’d like is a VERY crisp-handling, street car. So far down here I run into shops that either ask me “What do you want….” which I can’t really answer specifically. I know suspensions are all a set of compromises ;-). I’d like a street Si that handles like an old Lotus Elan ;-). The stock car is surprisingly good–darts around well, but with just a bit quicker reaction to driver inputs and an overall “tighter” feeling in the twisties.
stp
March 20, 2008 at 10:11 pm
Well Stephen,
The biggest problem you’re looking at right now is the 70/30 weight balance of a stock CRX. I suggest a mild once-over of the stock suspension. As I recommended here, H&R Sport (not Race) springs and KYB AGX struts are a good idea, and a larger rear sway bar will help to stiffen the rear a little and control that understeer you constantly fight. If that’s not enough, you can get a smaller front sway bar, or get a strut bar for the rear.
If you’re really serious about learning, it’s probably a good idea to go take a driving course. I don’t know what instructors have good repuatations down in SoCal, but you could certainly head down here:
SCCA
to get some good recommendations. A driving course will help you to nail down exactly what your wants and needs are in addition to giving you a practical hands-on understanding of vehicular physics. A book can offer a lot, but nothing’s the same as serious seat time.
Don’t make huge modifications all at once, try to make small changes and get used to the difference in driving before going further. It’s easy to screw up your suspension geometry by doing too much all at once.
Good luck, and take lots of pictures!
March 21, 2008 at 6:52 pm
Thanks Jesse. All good advice. Since I NEED to replace the brakes and the rear control arm bushings, I’ll do that first. Is it worth getting drilled or slotted rotors or just get the solid Brembo’s for a bit less? Or do you have any specific recommendations for a rotor and pad combination? Ditto on the rear control arm bushings. I know neither of these things is going to make any radical change. Then it would be onto the H&R springs and AGX shocks. Do the H&R springs lower the car at all?
I’ve had quite a few Porsches, mostly 944 Turbo’s/S2’s and one Boxster S. I’ve done one full weekend DE event with the Porsche club, but I’m still a very novice driver. I love the light feel of the CRX, but the front wheel drive still feels funny to me when I try to push it a little. I good course with the CRX would probably be just the thing.
How do you post pictures here?
March 21, 2008 at 11:07 pm
Drilled rotors are often a bad idea (unless they’re Porsche, which is a different story altogether), and slotted rotors weaken the rotors slightly while decreasing brake fade. If you’re on a track, it’s a good idea because you’re likely to run into brake fade when racing really hard. If it’s a street car, it’s not going to gain you anything, and will decrease your response time slightly. You’ve inspired me to write an article on brake rotors specifically, since it’s such a hot topic.
I definitely suggest going with blank rotors regardless of price. You end up with a larger contact patch and have to replace pads less often that way. Since you won’t run into brake fade on the road (if you are, you shouldn’t have your license), there wouldn’t even be a theoretical advantage to slotted/drilled rotors anyway!
On pads, just get something decently priced. Don’t get race pads, because they street driving won’t even warm them into operating temperature.
As far as the bushings go, they make more of a difference than you’d think. They help transfer weight directly to the steel of the car (body and suspension) and tighten up the ‘feel’ of it. I had an Energy Suspension kit that I mostly installed, and was very pleased with the results. Make sure you grease the bushings before putting them in, otherwise they’ll squeak like there’s no tomorrow!
On the shocks/springs, H&R has two levels that I’d recommend: Sport (about a 1″ drop or so) and Race (about a 2.5″ drop or so). If you’re driving on the street, DEFINITELY go with the Sport springs. Race springs will have you scraping the precious underside of your car all the time, and cause fender rubbing in most cases. I say moderately stiff springs (H&R Sports) are the best way to go.
On your previous cars, I’m actually very interested in Porsches. I’ve driven the 944 Turbo, which was a blast. You can definitely tell that the transmission is actually in the back of the car, and the engine in the front. It’s nimble, almost twitchy in my experience. Going from that to the understeering CRX is a whole new world, but a very worthwhile experience. If you get the chance, try driving a race-prepped truck at some point. It really shows the extremities of a vehicle’s capabilities right away.
On pictures…
I’ve actually been looking into featuring some other peoples’ cars lately. If you’d like to be the first, shoot me an email at drummingpariah (at symbol) gmail dot com. I had a features section up for a short time in hopes that I’d be able to populate it, but too many other things came up all at once. Now that things have settled, I think it’s a more realistic project to tackle.