Different kind of CRX Project - Tuner-Junction

njn63 · #1 (**permalink**) December 14th, 2007, 07:59 AM

Well, with graduating i'm going to be going back to driving my HF for a few months so i'm going to push it towards getting better gas mileage. Already planned is a minor weight reduction, partial grille block, cutting the back bumper, and possibly a lower air dam along with all the general maintenance shit the car needs.

Just curious if anyone has any other suggestions. I have a few things in mind based off of the Insight's aerodynamics package but i'm not going to cut the car up (all weight removal will be truly unnecessary material, nothing effecting safety).

The goal is to have a car that realistically gets 50 mpg average. Doesn't sound crazy considering it's rated high stock but for some reason the car gets anywhere from 36-46 mpg depending on weather/driver. I think the major thing holding it back is the wheels (they're some heavy alloys off an Accord I think) so I might source a set of VX's down the line... i'd put my HX rims off my Si on it but they have Falken Azenis on them, not a good idea in snow.

I'll document progress as it comes and take some pictures of this beast so you can all appreciate the awesomeness.

Calicab · #2 (**permalink**) December 14th, 2007, 11:09 AM

what excatly is a minor weight reduction?

im missing AC and all components, carpet, all sound deadening, all my rear plastics, my pillar plastics,and my headliner.

minor or not?lol

i look forward to it though

njn63 · #3 (**permalink**) December 14th, 2007, 12:49 PM

Quote:

Originally Posted by Calicab

what excatly is a minor weight reduction?

im missing AC and all components, carpet, all sound deadening, all my rear plastics, my pillar plastics,and my headliner.

minor or not?lol

i look forward to it though

I'm sorta curious myself haha. I'm a stickler for keeping most of the interior too so it'll probably be less than what you've done. I'm just going to go over the car a lot because I've never really driven it much... I only bought it because I got a deal that I couldn't pass up and then kinda just threw my dad the keys to it.

sloganish · #4 (**permalink**) December 16th, 2007, 04:16 PM

just buy a honda insight, thier like 6-7k and get 50mpg with all the accutrements!

Ice78Transam · #5 (**permalink**) December 16th, 2007, 06:59 PM

Just pay your grandma to drive the HF for you. that should do the trick

njn63 · #6 (**permalink**) December 18th, 2007, 03:10 AM

Quote:

Originally Posted by sloganish

just buy a honda insight, thier like 6-7k and get 50mpg with all the accutrements!

Um... I have under $500 in this HF total right now. It'd take 10 years to pay off the difference in price with gas. Never mind the amount of CRX parts I have so that maintenance is virtually free.

Plus, this is more about knowledge than the actual money.

jon ROCKS!!!! · #7 (**permalink**) December 18th, 2007, 05:31 AM

turbocharge = gas mileage

ATISTANG · #8 (**permalink**) December 18th, 2007, 07:35 PM

i swear i picked up a few mpg after gutting my cat

A_White_Gs-R · #9 (**permalink**) December 19th, 2007, 10:58 PM

probably cuz your cat was so fucked up. But couldnt have been that much bruce.

jon ROCKS!!!! · #10 (**permalink**) December 20th, 2007, 02:43 PM

Quote:

Originally Posted by A_White_Gs-R

probably cuz your cat was so fucked up. But couldnt have been that much bruce.

fuck yoru cat

A_White_Gs-R · #11 (**permalink**) December 20th, 2007, 05:41 PM

Quote:

Originally Posted by jon ROCKS!!!!

fuck yoru cat

You mean his cat. I threw my shit away. No cat for me.

ATISTANG · #12 (**permalink**) December 22nd, 2007, 07:38 AM

Quote:

Originally Posted by A_White_Gs-R

probably cuz your cat was so fucked up. But couldnt have been that much bruce.

i meant a couple, 1-2. and really the cat looked good, just out here in redneckville they don't have smog so while i had it off i ran an air hammer down through it a few times lol

Nick you could also run your tires at there max psi instead of what is recommended for the car, it won't make a huge difference but it will help. Also a Y7 manifold might also help out, aside from more efficient i think they are also lighter.

Plexiglass windows in the rear

macbasq · #13 (**permalink**) December 22nd, 2007, 04:21 PM

Place a wood block under the gas pedal so you can't go WOT. It'll make merging on the highway scary as shit but think of all the gas you'll save haha.

njn63 · #14 (**permalink**) December 26th, 2007, 05:28 AM

I havn't done shit of course. Got the windshield fixed and havn't even driven the car since (that was a week ago). Stupid holidays/cold/laziness/ebay sales.

The cat is staying only because i'm turning into too big of a hippy to polute more. I'm planning to block the grille tomorrow if I have time before I go to AFA. The tires have been inflated to 42 psi a few times (i think that was max) but they leak down to ~35 in the matter of a few days, lame. The y7 manifold isn't a bad idea, i'll have to look into people's experiences with them.

Most of my research said the complete opposite of what I expected but it makes sense now that I think about it. For better fuel mileage you want to retain heat in the engine bay and increase IAT's. I was reading about one guy swapping in a 193 degree thermostat in place of a 173, warm air intakes picking up 3 mpg on Saturns, so weird. I've spent so long trying to reduce them that it's almost a challenge to think about ways to do the opposite.

If I actually accomplish anything tomorrow I'll take pictures.

macbasq · #15 (**permalink**) December 26th, 2007, 02:27 PM

Quote:

Originally Posted by njn63

For better fuel mileage you want to retain heat in the engine bay and increase IAT's. I was reading about one guy swapping in a 193 degree thermostat in place of a 173, warm air intakes picking up 3 mpg on Saturns, so weird. I've spent so long trying to reduce them that it's almost a challenge to think about ways to do the opposite.

That makes sense though. Cooler air is denser than warm air, so if you've got more air going into the engine you need more fuel to maintain a good stoichiometric ratio. Let things heat up and you'll lose power but use less fuel.

Pooch 1069 · #16 (**permalink**) December 29th, 2007, 08:03 PM

How do you properly block a grill? I wouldn't mind going for higher gas mileage on my B for the winter. I already get around 30mpg but would love to see it closer to 35-40. I have my stock intake on right now, does a high flow filter like K&N actually increase gas mileage?

njn63 · #17 (**permalink**) December 29th, 2007, 09:52 PM

Everything i've read has said that a K&N doesn't help mileage much unless your filter is really dirty.. but I swear it helped my dad's truck.

I'm using plexiglass on my bumper and blocking it permanently around 60%. I made 3 aluminum L brackets and bolted them to the bumper which i'm sure you don't want to do to your car but you could probably do it with any type of plastic and some zip ties. Someone cut all the cross ribs out of my HF's grille so I don't have that option unfortunately.

I don't like how he glued his in but here is a how to: crxMPG.com - DIY CRX Grill Block I really don't think blocking the pockets on the side (where fog lights go) does anything either but I have nothing to support that.

The main reason i'm focusing on aerodynamics first is because I mainly drive this car on backroads at highway speeds:

Quote:

Originally Posted by http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=29

During stop-and-go city driving, it's estimated that overcoming inertia is responsible for about 35% of the vehicle's resistance. Driveline friction is about 45%; air drag is about 5% and tire rolling resistance is about 15%.

Overcoming inertia no longer plays an appreciable role in the vehicle's resistance during steady speed highway driving. For those conditions it is estimated that driveline friction is about 15%; air drag is about 60% and tire rolling resistance represent about 25%.

o1racing03@aol.com · #18 (**permalink**) January 7th, 2008, 01:38 AM

Quote:

Originally Posted by ATISTANG

i meant a couple, 1-2. and really the cat looked good, just out here in redneckville they don't have smog so while i had it off i ran an air hammer down through it a few times lol

Nick you could also run your tires at there max psi instead of what is recommended for the car, it won't make a huge difference but it will help. Also a Y7 manifold might also help out, aside from more efficient i think they are also lighter.

Plexiglass windows in the rear

He mentioned tire pressures ,but think about this also ,find the tallest ,skinniest tires you can and inflate to max pressure .Back in the day thats what VW did to set their records .They almost looked like bicycle tires and were hard as rocks with pressure and it made a considerable differance.
Though not great mileage but surprising to me I went to Fla last year and got 372miles on 12 gallons at a constant 80 to 90 miles an hour,thats 31 mpg with a B16 CRX dx,even upping it to 100mph on a few stretches. Its not the 40 mpg I got with 285k mile D15 motor I took out ,but I like the extra 100 hp nowand it seems it doesnt matter if i'm around town or freeway ,it gets 31 mpg.
Back in the 70s I went with a friend to Las vegas in a Chevy Cheyenne P/U,He hooked up a manual choke cable to his distributer and had an onboard computer once we got rolling on the freeway he would just dial the dizzy in to the best mpg.

njn63 · #19 (**permalink**) February 15th, 2008, 02:48 AM

Last tank = 39.6 mpg

Thinking weather had an impact on that and i'm not really babying it. My brother picked up an Insight so now I have something to copy off of. Still debating if I want to tin up the bottom of the car and still havn't even cut the rear bumper.

Actually have been spending most of my time trying to fix issues with the car. Car is a textbook example of why a good deal initially on a car can turn into a bad deal fast.

ATISTANG · #20 (**permalink**) February 15th, 2008, 09:50 AM

Quote:

Originally Posted by njn63

Last tank = 39.6 mpg

Thinking weather had an impact on that and i'm not really babying it. My brother picked up an Insight so now I have something to copy off of. Still debating if I want to tin up the bottom of the car and still havn't even cut the rear bumper.

Actually have been spending most of my time trying to fix issues with the car. Car is a textbook example of why a good deal initially on a car can turn into a bad deal fast.

lol i used to get 38mpg with my dx.