Remove cat on high milage Festiva for school competition?

[bassman]

The local high school is having a milage competion this summer and my friends boy wants to use one of my parts festivas.

I run my cat because its never been a problem and from what I hear it does not help milage anyway??
OR does it??
being that this is a competion and not a car that will be driven other than that day will removing the cat help?

[Spike]

I.. of course, have a catalytic converter.. on mine.. because it's the law here in Indiana. >_>

But I don't think the cat affects our engines much, nor does it affect the o2 sensor, as it's placed on the manifold. To what I've read, taking the cat off is 8 or 10HP boost... my little auto can get to 60 in about 11 seconds... with the cat on, of course.

~Joe

[Movin]

If the cat has failed..take it out.
for mileage take out everything that weighs anything.
Jack the timing and clean the fuel system..
get low rolling resistance tires or 12 inch scooter tires and use over tire pressure.
use really light oils where you can.
EXAMPLE: Mobile one 0 w 20 motor oil for the transaxle..
move the o2 location closer to the edge of the pipe.
inject HHO, 02ho or anything to dilute fuel and add power.

[econoaddict]

88 Carb'd 5spd, removed the cat and did my daily drive for about 2 weeks (100 miles a day) mileage went down a good chunk, put cat back in mileage returned. I think it had to do with not enough restriction during normal rpm driving.

[25Horseplay]

A good site to check out for mileage tricks is http://ecomodder.com/ They are a great group of guys there!

[WmWatt]

I'd read the rules for the competition and see what they're looking for before playing with the car.

As for the catalytic converter, I'm just guessing here but the computer is programmed and calibrated to
optimize fuel efficiency with the converter installed. See if you can find out anything on the Internet
on how the computers work. I read both the Haynes emissions manual and an auto engineering text on emissions
from the public library years ago. Good places to look, IMHO.

[Movin]

The cam and cam timing affect how an engine handles back pressure. The computer in the festiva and aspires do not control cam timing so changing the back pressure by removing the cat, adding headers or a larger free flowing exhaust would need a small cam timing correction to keep raw fuel from being sucked into the exhaust before the exhaust valve closes. Mileage being first priority will make some of the engine mods a little different than what you would do for horse power mods, some are real similar as efficiency improvements help both with the proper adjustments.

[bassman]

The rules are basic but extra points are given if your car beats what the gov gas milage est website says your car can get.

they also want a list of things that you did to increase the milage like overinflated tires or fuel additives ect.

as far as cats go I was told that a car that burns oil will plug it but I would think that it would clean itself out on a highway trip cause of the high heat ??
\

[Tommychu]

I'd read the rules for the competition and see what they're looking for before playing with the car.

As for the catalytic converter, I'm just guessing here but the computer is programmed and calibrated to
optimize fuel efficiency with the converter installed. See if you can find out anything on the Internet
on how the computers work. I read both the Haynes emissions manual and an auto engineering text on emissions
from the public library years ago. Good places to look, IMHO.

Festiva ECU has no idea what's going on in the exhaust system after the manifold. Movin knows what's up. To see benefits from a de-cat you'd have to mess with the cam and that could have other adverse effects.
What kind of speeds will this thing be seeing in the competition? If it's going to see anything near highway speed I'd gut the interior and then tape up all the body gaps with foil tape. Cutting a coil or two out of the stock springs would help the aero immensely as well. If it's more of a low speed thing I'd look at removing glass(not the windshield, that's structural in most unibody vehicles), the hatch, bumper supports, hood, fenders, etc. Also cutting out all nonessential wiring would free up a few pounds.

The rules are basic but extra points are given if your car beats what the gov gas milage est website says your car can get.

they also want a list of things that you did to increase the milage like overinflated tires or fuel additives ect.

as far as cats go I was told that a car that burns oil will plug it but I would think that it would clean itself out on a highway trip cause of the high heat ??
\

If you want to clean it out run a can of seafoam through it. Don't use any other additives.

[bassman]

Looks like the coarse will be a police controlled 30 mile stretch of highway that has a uturn at each end so you simply go back and fourth on a 2.5 gallon can of gas that is given to you at the start when your car is run dry.
Your car has to drive up and run till it dies if your stock tank in in place or you can use a tank like a boat has or any container but it has to be empty and die with no gas at the start.

then you drive at 100km an hour average and they will clock you at 1km each end..

[nitrofarm]

Also to add to the above suggestions....
Aspire head or Aspire valve train.
Adjustable Fuel Pressure Regulator
Fresh Bearings and grease at all 4 corners
O deg off toe front/rear
Make sure you dont have any brake drag
Check bearings on H2O pump & Alt
You could even install a switch to shut off the "Field" circuit in the alt and simply run off battery,obviously dont run fan/radio etc...
You could also consider running a very small lawn/garden battery for the competition as well. Because all you need power for is the ignition.
Like moving said get rid of weight,but if this is you DD you might not want to remove your heater core,wiper motor etc..The list goes on & on,but if a "Gutted" Festy cant win this contest something is seriously wrong.Good luck and keep us posted!

[DriverOne]

Re: Remove cat on high milage Festiva for school competition?

Your only real competitors would be a CRX or a Gen 1 Geo Metro hatch. A lot of the ideas here are pretty extreme. I'm pretty sure that since the cops are in on the competition that the car is going to need to be road legal. At 62mph, that's right at optimal cruising speed anyway. I hope your friend's son can drive a stick. If not, I don't think he can win. The autos at 35mpg are far inferior to the manuals at >44mpg. A Chevy Cavalier could be a close competitor in the 35 range. Anyway, I agree with taking out the seats, but I should mention that the 44mpg I speak of was in my wife's 90 L+, loaded with two people at ~200lbs and a loaded down cargo area with two coolers, folding chairs, two spares, two duffel bags loaded with clothes, fishing equipment, blah blah blah. There's no need to strip the thing bare. Aero is where it's at. I would surely look at taping the doors, hatch, and front end trim. Maybe remove the back bumper, or at least tape it off so you don't get drag there. Maybe try Nitrogen in the tires. Otherwise you're practically cheating just using the car. I would love to see a video of the race! The way I see it, 175km out of that car is possible. Just remember what Jeremy Clarkson said: Braking destroys efficiency! Smooth, gentle descent from speed for the turnaround as much as possible, and a mild acceleration back to speed should have your friend's son passing dead cars in no time. Good luck to you!

[crazyrog17]

Remove cat on high milage Festiva for school competition?

Coast and burn shut down the engine on the way into the corner and coast as long as you can. Keep enough speed so at the turn you can pop the clutch in second to restart the engine. Take off slow and shift gears soon, no high revs and no heavy foot.

[Movin]

If the race course is mostly steady speed on flat ground the race will be won with rolling resistance and slippery mods. Weight plays a part but is not as big a part, it can help rolling resistance and of course your two accelerations. Tires are probably your biggest factor for rolling resistance, research this well. Lubes and greases make a difference. New brake caliper piston seals are more flexible and will pull the piston back from the rotor, glue the pad to the piston, and lube the caliper mounts so they truly float the assembly.
On the rear lube all contact surfaces of the brake shoes so they glide smoothly in and out when used. Back off the adjustment so there is some clearance then disable the self adjuster.
If you use hyper mileage driving techniques remove the steering lock for safety, one step too far in the ignition will move your concentration from racing to car control!
As far as aerodynamics, it is hard to get better than the shape of a BD-5 airplane's fuselage. A member named Darla I think has played a lot with fill in and add on shapes as well as sealing tape and other things on a festiva.
Most important...everybody have fun and take lots of pics!!

[nitrofarm]

The first portion of the contest you'll only be turning @ 4 times (if you average 50 mpg). So while making smooth non fuel wasting turns will help,the cars fuel sipping ability is going to be be the biggest factor.IMO the biggest factors are going to be final drive ratio,vehicle weight,friction & aerodynamics. So strip down the car & put the biggest tire dia you fit under the car. A gutted Aspire would do very at this contest.