Project: modding sixth gen Corolla sedan on a budget
 

Name this project!

Goals:

• Save up, get rid of it and get a Prius. :p
• Practice ecomodding. Hopefully make it look good or at least have some nice looking bits on it so the wife won't feel so nervous when I go after her Civic, or the Prius.
• Have fun.
• Improve mileage for a given speed.
• Try to keep mod ROI under 7,000 miles.
• Keep it running healthy and keep emissions down.

I'm going to be editing this first post for index, status, and current pics.

Latest results: 46 MPG @ 65 MPH for 1300 miles! Stock Cd of 0.36 reduced to 0.28 (maybe).

Outdated pic:
http://ecomodder.com/forum/attachmen...1&d=1351489789

Finished mods:

1. $33 - Smooth wheel covers.
2. $15 - Rear wheel skirts. (Coroplast on steel strip.)
3. $35 - The air dam is dead. Grill block, and gap filler. Air dam early on. Braces and opening. Refinements and upper grill block. Broke the corner, painted it, repaired it, ducted it, cut it higher and added a soft chin. Death of the air dam.
4. $15 - Passenger mirror delete. Added wide angle rear-view mirror.
5. $62 - Block heater (here is a tutorial I wrote)

Other mods I hope to finish:

• Air dam.
• Side skirts (look at how the stock body curves in on the sides, that's gotta penalize drag on the wheels)
• Aero hood cowl to streamline windshield wipers
• Soften edge radii on front wheel wells
• Kammback
• Spoiler or Box-Cavity combo
• Killswitch

Mechanical condition:

• Fixed! Rolling resistance high when cold. Primary problem: high viscosity of 75W90 tranny oil, switched to Honda MTF. another cause in the transmission. Secondary problem: drum brakes need to be turned. Got the 'self-adjuster' in a better spot (doesn't self-adjust anymore), but still need to turn or replace the drums.
• Abnormally severe groove wander. Could be the shocks?
• Shimmy at 70 MPH (but when do I drive that fast?) Could be the shocks?
• Leaky trunk
• Broken parking brake equalizer
• Fixed! (AAP diaphragm leak) Rough idle See Carb rough idle

Enjoy!

I forgot to mention: this car does not have an overdrive, despite having a 5-speed manual transmission. It also lacks a cruise control. Solution: P&G - reduces throttle loss and keeps my heel moving around so it doesn't get sore. Too bad the carburetor makes it a poor candidate for EOC / killswitch. Or does it?

Aero front-end mod plan, grill blocking and smoothing
 

I feel that the stock bumper design is particularly crummy aerodynamically. I wouldn't be surprised if I have 5-10% to gain here without too much effort.

I failed on the first attempt, but learned how to gather good coast-down data and discovered that I have a mechanical problem (BTW, now I think the problem is the rear drum brakes). http://ecomodder.com/forum/showthrea...ast-23162.html

Edit: I took off my v1 "bullnose" this morning. I'm certain I can hear a lot more turbulence against the windshield and hood without it, with a sudden onset around 55 mph. Although my bullnose didn't work properly, probably due to the open sides, I'm even more convinced that my aero eye is correct; the stock grill-to-hood angle / radius on this car is a disaster. A grill block by itself would not fix the problem.

Anyways here is a crude photochop of my v2 mod design - more conventional ecomodding:

http://ecomodder.com/forum/attachmen...1&d=1349292032

I've got 1/8" clear PETG to go above the bumper, although I think it would look nice to paint it black over the grill location. Below the bumper I'm thinking coroplast, reinforced with coroplast, unreinforced at the bottom 4 inches so it can fold if it scrapes. The blinkers you see low on the the bumper will either get moved forward or clear covers. The cooling inlet will be bottom middle of the coroplast. I might hand-mold a smooth inlet trim. Cooling ducting would probably not be very aerodynamically effective without more distance between the mod and the radiator, so I might not bother.

As a tangent, the 4x8' 1/8" PETG rolled up without too much trouble and fit in my back seat, which is good because the seats don't fold. It was about $90 = $2.80 per sqft.

http://ecomodder.com/forum/attachmen...1&d=1349292239

PETG top-to-bottom would be a little cost-prohibitive here. My motive is primarily environmental, which also means evangelical, but I aim for cost-effective energy reduction. That's what I really mean by shoestring budget. This car isn't going to see that many miles, in my possession. So I'm trying to keep mod ROI down to ~7,000 miles. That sets the bar pretty low, like $33-$66, depending on whether this is a 5% or 10% FE mod. Most of the PETG is going to be for the Civic.

I'm subscribed! Should be interesting.

Going across country next week? Then make sure you pump up the tires and that you slow your speed. Those two by themselves, free and quick, will save you bigger percentages than most other things, if the experience of this group means much. Good luck driving cross country! I love long road trips. Love 'em.

My logs don't reflect it very well, but I'm pretty good at hypermiling. The Civic's SGII reports 55-62 MPG for my round-trip commute when I drive it. (The Corolla logs are probably mostly limited by mechanical problems, and the Civic logs limited by its owner, who doesn't hypermile quite as well as I.)

I'll probably be around 5-10 under PSL, for MPG and the fact that I'll be alone. Also I don't know yet whether the mechanic will be able to fix the shimmy that set in at 67 MPH when he looks at it tomorrow.

That being said, I'm afraid I have exactly the opposite feeling toward long road trips. Time spent driving is time I wish I could spend on something else. I have several neglected hobbies, in addition to several active ones. Plus a house and kids. One of my hobbies does not happen to be books-on-tape.

Aero is the magic genie of vehicle optimization. Or automation and road trains, even better. Or all together, even better.

Actually I would prefer a greyhound for this trip, all other things being equal. Unfortunately the greyhound's schedule happens to be awful for this route (12am - 2pm or 12pm to 8am - I really like to sleep in a bed).

Another 10 minute pre-road trip must: quick 'n' dirty partial grille block. It's one of the best ROI mods in terms of fuel saved for effort expended.

True generally. But I added a comment yesterday you might have missed (sorry about my editing habits):

To my eye there is a similar problem on bottom - below the bumper - although I wouldn't expect to be able to hear the turbulence as clearly.

The timing belt gets first dibs on my time, but I'm optimistic about finishing that and having time left over to fabricate my target mod.

I'd bet the opposite - it's just fine. A 5-minute tuft test will probably show everything is as it should be - attached flow streaming smoothly away from the leading edge of the hood.

EDIT: maybe you mean something else by "disaster"?

That's a good idea. I'll have to see if I can find the yarn when I get home. (That is indeed what I meant.)

EDIT: I started working on the timing belt, tufts will have to wait for the weekend.

I did the tuft testing, with and without a cardboard / tape mod to smooth the grill and headlight area, and I agree with you. The flow looked the same either way. There was a bit of a turbulent spot in the lower middle of the windshield. Perhaps because of the windshield wipers.

So, my question is, should I just focus on grill blocking and air dam? The idea I drew earlier included a clear plastic transition smoothing from the bumper to the hood. That seems unimportant now.

My thinking is that the point of stagnation is the most important result of the air dam. Ideally I want it to start at the existing point of the bumper and slope forwards to get as much air up and over the car rather than under it.