Cal Club Autocross Forums

Mako Koiwai wrote:Watch that Steering Lock!

watch that lack of engine vacuum effecting your brakes.

Marshall Grice wrote:

Mako Koiwai wrote:Watch that Steering Lock!

watch that lack of engine vacuum effecting your brakes.

Both of those little drawbacks seem like they could cost more than the gasoline saved.

Bob Beamesderfer wrote:

Marshall Grice wrote:

Mako Koiwai wrote:Watch that Steering Lock!

watch that lack of engine vacuum effecting your brakes.

Both of those little drawbacks seem like they could cost more than the gasoline saved.

I would never recommend using P&G because it would annoy the crap out of everyone behind you and could lead to getting shot. But the Prius has electric steering and probably electric assit brakes.

I drive an Acura TSX over 20k miles a year. I get around 30 MPG. I love that car and comfort is important since i have a 1 hour commute to work each way. I would like to get better milage. I really like the Fit, but it needs the Civics bigger motor (they get the same milage). i heard the new TSX diesel might get 50 mpg.

They stopped making the Insight a little to early. I saw 2000 Insights for $13K! When is the CR-Z going to be here?

Hey, Acura, listen up, i want a luxury Fit with the civic 1.8L in it or the 2.2 diesel and a dead pedal and a center arm rest. I'll be a happy man then.

FIT for Me 2, as a DD

Has anyone ever done a gas->electric conversion? My idle daydreaming has been of that lately. Here is a blog I've been watching.

Pat.

Darren Cole wrote:I saw 2000 Insights for $13K!

A 2006 Insight sold on Ebay last week for $26.5K. Sticker was like 23...

Oh yeah...Pat, check out 'Zap Motors'. Think they're in Santa Rosa. They'll do everything for you.

One way to improve mileage is to add lightness. The Elise did over 34mpg on freeway. The Noble is doing 28.5mpg freeway.

Randy Chase wrote:One way to improve mileage is to add lightness. The Elise did over 34mpg on freeway. The Noble is doing 28.5mpg freeway.

Lightness matters for acceleration (stop and go traffic) and hill climbing. Highway crusing is mostly about rolling resistance and aero drag.

This guy did a few minor mods to reduce his aero drag:

http://blog.wired.com/cars/2008/01/more-details-ab.html

And this guy sounds like a total jackass driver:

http://www.motherjones.com/news/feature ... ilers.html" onclick="window.open(this.href);return false;

One way to improve mileage is to add lightness.

You must have been reading up on Colin Chapman. "Add lightness" was one of his favorite phrases.

And this guy sounds like a total jackass driver

OMFG what a self-centered tool. Getting good gas mileage is one thing but this guy is going to get shot.

Look at this one. This is an example of when money is no object, apparently. Nearly $16k for motor/batteries/ultracaps. I don't see any performance numbers anywhere, but the project sure is clean. I like the idea of using the ultracapacitors as "electronic NOS", sort of.

Pat.

Will Kalman wrote:

Randy Chase wrote:One way to improve mileage is to add lightness. The Elise did over 34mpg on freeway. The Noble is doing 28.5mpg freeway.

Lightness matters for acceleration (stop and go traffic) and hill climbing. Highway crusing is mostly about rolling resistance and aero drag.

I used to think that, but I think the weight does matter at freeway speeds. As the speed goes up, the air resistance becomes the bigger factor. Because even if maintaining a steady 65mph, you are actually accelerating constantly.

Randy had one of the first Elises ... and visited the factory a number of times. Or was that Robert P?

Mako Koiwai wrote:Randy had one of the first Elises ... and visited the factory a number of times. Or was that Robert P?

Both things are correct about Robert and I.

Randy Chase wrote:I used to think that, but I think the weight does matter at freeway speeds. As the speed goes up, the air resistance becomes the bigger factor. Because even if maintaining a steady 65mph, you are actually accelerating constantly.

Physics called and wants to have a talk with you... Acceleration is change in velocity.

About the only way that I can think that light weight can help aero drag would be due to the narrower tires it could run, all other things being equal. Rolling resistance would be reduced slightly, owing to less tire flex (or flexing less tire).

The Elise is a small car with a modern engine. Why wouldn't the Elise get Celica-like mpg considering it's mostly the same engine on a similarly-sized car (aero-wise)?

Randy Chase wrote:Because even if maintaining a steady 65mph, you are actually accelerating constantly.

Academically, you’re not accelerating at steady 65. Your energy is going against the wind though (rolling resistance is a small component vs wind at this speed), not against momentum or gravity. Force of wind is surface dependent (no mass variable in the equation), where going up hill and actual acceleration have mass in the equation.

It can feel that way because heavier cars are typically bigger (more surface area) with bigger motors (less 'cruising' speed efficiency).

Jay W

OK... change the word ACCELERATION with "actively applying throttle to moving the car forward." In real world, and in real driving, you have to adjust the throttle to maintain a steady state. That means pressing the gas down. Be it to pass, go up an incline, etc. And then weight matters.

I find it odd that a 500+whp car can get over 28mpg. Happy about it... not complaining.

Randy Chase wrote: Because even if maintaining a steady 65mph, you are actually accelerating constantly.

Huh?

Sheesh. Poor choice of words. I meant that one was not coasting.

Y'all need to be nice to Randy - he's a design guy, not a physicist. ;D Having worked with some of his work-product, I can also say that Randy is pretty damn talented when it gets down to it.

There is a component of the equation that weight factors into, but the contribution at steady-state conditions isn't predominant. The question is how significant the weight component is, and that's probably going to be highly dependent on the effective 'density' of the car - how much it weighs relative to frontal area, tire behavior, etc...

No black hat/white hat answers...please. :gpower:

Edit - a link so awesome I just had to add it. Also, check out the turbo-dorks on the Wikipedia 'physicist' page...

"More Please" - http://www.ananova.com/news/story/sm_1337537.html
http://en.wikipedia.org/wiki/Physicist

And keep in mind, English is my second language and I only finished 9th grade. :gpower:

I once towed a big huge box (5x8 Uhaul trailer) out to CA and back to KS with the Altima. I actually got better mileage with a thousand pounds or so in the trailer vs. towing empty. I think that the extra momentum helped offset the extra drag. Coasting downhill empty in neutral, it would slow down to about 40mph on a 7% grade, although the Altima had the hp to get it to well over 100mph (for about 2 seconds, then sanity returned).

You still have the pics of the last time that Altima towed???

I'll jump in late on this, but I can really attest to the damage that 'blown" tires can do. I drive the 710 a lot. It has a minefield of blown tire parts on it. Twice cars in front of me have kicked up chunks of gators. They both hit hard and one did an amazing amount of damage to the front hood of my Previa. I wouldn't ride a motorcycle on the 710.