Yet Another CRX HF

[mrmad]

Howdy,

I decided I'm putting too many miles on my Integra GSR back and forth to San Diego everyday (40 miles each way), and at over $3/gallon, the 30mpg it's getting isn't enough. So now I'm the proud owner of a 90 CRX HF.

It has 176K miles on it and I paid $2000. Maybe too much, but I have my project car. It needed a new driver's axle ($65 at Autozone) and needs a new climate control as the original is broken in half. I guess this is normal for 88-91 CRX's. Seeing that unbroken ones on Ebay are going for almost $100, I'm trying something different, I got one from an 01 Altima for $29. I'll let you know how it fits. I'm hearing some ominous sounds from the tranny that make me think I may have some bearing problems (don't let the owner crank the stereo when you're test driving it, there's a lesson learned). It has a header/cold air intake, but I also got the stock parts with it.

The car also had a stuck thermostat preventing the temp guage from even moving from C in the early morning. I drove it last week to work like this (with the 24psi in the 14" civic wheels it has) and got 41.4mpg after 304 miles of probably 70/30 freeway/city. The traffic on I-15 seems to be imitating the Autobahn and I think I'd get killed if I tried to go below 65, so maybe 41.4 isn't too bad.

So now I'm on my 2nd tank with a working 180 degree thermostat and 38psi in the tires. Hopefully I'll see some gains.

My plans are to put a wideband O2 sensor in it to see what the AF ratios the stock ECU is giving while cruising on level ground and climing the small mountains north of San Diego on I-15. If it is near the 14.7 in closed loop at cruising that I think it will be, I may go all out and put a Megasquirt DIY ECU, and car PC so I can data log and tune the thing to get it as lean as possible without blowing it up. My God, I'm really turning into a geek here, but I guess I'm in the right place.

If anything, the car is an instant way to make my Integra feel like a new car.

Sorry for such a long post and thanks for all the information on this site

[SVOboy]

Don't worry about megasquirt, just convert to obd1 and modify a stock ecu.

Good luck, good to have you around.

[mrmad]

I've looked into both the OBD1 covert and Megasquirt and believe that I'll have alot more control over the tuning with it then an OBD1. The Megasquirt has a serial output that I can connect to the in car PC allowing me to data log and retune the car without having to burn a chip as well as create a VB live set of guages including an MPG guage. You can't do that with an OBDI stock ECU.

[SVOboy]

Sure you can, it just requires a bit more ingenuity,

[The Toecutter]

The CRX is an excellent base to build an extremely fuel efficient car. Nearly 60 mpg is possible without modification and just good driving technique. Phil Knox has gotten over 90 mpg highway after extensive aerodynamic modifications with his CRX.

[Gary Palmer]

Welcome to Gassavers.


In my opinion, I wouldn't be trying to put a megasquirt into an HF. Your in California and you have to pass the smog test every two years. If you go with a stock system you can do that without trying to reinvent what Honda has already done. The HF appears to very capable of getting 60mpg, on the highway and your right, if you try to drive less than 65 on that freeway, you'll get in the way of traffic and create a hazard to yourself and everyone else. Additionally, with the HF, I think you can drive as fast as everyone else is and still probably get 55-60 mpg.

I have a 89 Honda Civic Wagon, with DPFI and I typically can get about 37 mpg, and drive in the inside lane, at whatever speeds everyone else is driving.

On the transmission, if you think you have bearings going out, I'd either try to locate a used HF transmission, so your ready, or I'd pull the transmission and get it rebuilt, or rebuild it. If the bearings are grinding, it's throwing metal pieces into everything and if you don't replace it pretty quick you can destroy the gears, as well.

If you get a used HF transmission, you need to check the gear ration, to make sure you are getting the right transmission. It can be pretty easy for someone to try to sell you a DX or CX transmission and end up getting the wrong gearing in your car.

Good Luck!

[omgwtfbyobbq]

I used to run on the I-15 between San Bernardino and the 91 at 55mph weekly with no problems. I went down to San Diego a couple times too at 55mph, but iirc that was on the weekends. I wouldn't be afraid of going 55mph on the I-15, considering I've been doing it on the I-10 (as fast or faster imo) for a year or so and haven't created any hazards. People aren't so stupid that they can't deal with a driver going slightly slower than semi traffic (which I am far more comfortable with than Joe Blow in the left lane) in the right lane. Occasionally I'll get some numbnuts in a big pickup/SUV coming up my *** having to drop 10mph because they don't seem to understand that if something appears to get larger, they're moving faster than it. But for the vast majority of driving I haven't had any trouble. In fact, I'm shocked at how conservative most people are... That being said, if you're scared going 55mph, go 65-70mph, it's not an issue either way. In fact, if you're really worried about it, find the slowest semi and tail it for the trip.

[MetroMPG]

Yes, welcome to GS, mrmad.

Another point to consider on the right-lane driving. A surprisingly simple tactic to use that will usually get people to go around you with no fuss is to communicate to them with your vehicle position: drive in the extreme right side of your lane.

I typically drive centered in the lane until someone begins to approach, then I shift over to the right. Doing it as they're approaching can draw their attention to you (more than if you're already over to the right), and they tend to just go around.

Something about hugging the right side of the lane communicates "I want you to pass me", which gets a better response than staying put in the center.

Experiment with it. You may be surprised.

[omgwtfbyobbq]

MetroMPG is spot on. Weaving noticeably between the lines definitely helps too, but you may not want to do it where cops hang out...

[mrmad]

Thanks for the suggestions. The traffic averages about 80-85 on this section of I-15. At 65, I'm continously getting passed, which I'm OK with. Any less and I think I'd eventually get rear ended, probably by some lifted F350.

I've searched on here and haven't seen too many instances of reprogramming the ECU to lean out the engine. Am curious if anyone has tried and what kind of results they had. As much as I'm sure Honda has done what they could, they were still restriced by emissions, which makes me think they didn't go much beyond 14.7 A/F. The civic vx has it's lean burn mode which apparently does increase mpg. If I'm programming it myself with something like Megasquirt, I do not see why I couldn't create a lean burn mode. I am curious if there is another 3-5% in possible mpg gains by trying.