Would You Believe This...

[mvftw]

I do all my own work on my cars (I have 5 now). The only work I can Not do is a NY State Inspection. I had it done a month ago on my Vette and I'm checking out the car today and there's NO AIR FILTER:eek, And last week I drove to the beach . Luckly I only had a little sand in the housing. It was a new Fram, but I'll replace it with a K&N. . Peaple ask me why I do my own work, now they know...I don't trust anybody touching my cars!!!

 

[sscam69]

I did that on purpose one time.
No hood, cold air (dry), no air filter.

Boy did I feel a DIFFERENCE!!:eek

 

[Ken]

I don't trust anybody touching my cars!!!

Frustrating, ain't it?

_ken

 

[Stallion]

I did that on purpose one time.
No hood, cold air (dry), no air filter.

Boy did I feel a DIFFERENCE!!:eek

What would the difference be? Higher hp because there's no air filter? Or no?

 

[GerryLP]

Stallion,

By removing the air filter one is effectively altering the fuel/air mixture ratio in the carb. A leaner (relativeley more air than fuel) mixture tends to increase Hp (all other factors being equal).

I dramatically saw this on my car's Dyno run on Friday. I removed the air cleaner to artificially alter the fuel/air mixture. My new Street Avenger 770 has size 72 jets (and these new carbs are calibrated at sea level), and dummy me went to the Dyno shop without additional jets to tune the carb. However, I was looking for Hp at the rear wheels, so removing the air filter moved the mixture from 10.5 to 11.5, and I saw a gain of 20 Hp.

 

[Scott81]

No air filter, that's not bad. My neighbor had his oil changed at one of those oil change places, they didn't put the drain plug back in.....you can guess what happened from there

 

[qwall]

No air filter, that's not bad. My neighbor had his oil changed at one of those oil change places, they didn't put the drain plug back in.....you can guess what happened from there

i seen it happen to my friends car, and it was done at a dealership

q

 

[BigBrakeFuelie]

 

[BlackNBlue95]

i seen it happen to my friends car, and it was done at a dealership

q

Mistakes happen some places are more prone to it then others but just depends on where you go.. me and my boss were talking the other day.. why do people always want to goto the place with the cheapest oil change.. shure you pay less but oil changes are the most single important routine matainence and usualy the less costly over any repair or other matainence item.. you usually get what you pay for example.. goto jiffy lube you'll be lucky if all your grease fittings get greased.. goto an independent shop.. they usually do more.. like my shop we also check the front end out look over the underside see if anything needs repair like a broken spring(yes you can have one and be unaware) or brake hose thats cracked..

Just get what you pay for most the time.. don't skimp.. and yes finding a trust worthy mechanic is one of the harder things in this world..
-Rick

 

[qwall]

that's why he went to the dealer, his car was under warranty and he didnt want anything to jepardize his warranty, at least he got his car fixed for free.......and you're right about finding a trustworty mechanic, it is hard but not impossible , the bad ones scare off people big time

q

 

[mvftw]

My friend went to a oil change place and a couple of days later he asked me about his brakes, the pedal was very hard. I said that is usually from a bad power booster, they I asked him if he went to a oil change place, he said yes, I said I bet they put tranny fluid in your master. I heard of that before. Sure enough they did, he had to replace the whole brake system about $1500 and they wouldn't own up to itad

 

[cruzer99]

I agree with everything that has been said.......Here's my .02....I was in a hurry one day and stoped at a "SPEED-DEE LUBE" for an oil change (usually I do my own), on my little Honda Accord, they cross theaded the drain plug. I didn't see the oil leak for a couple of days, took it back and of course they knew nothing about it.......450.00 for a new pan. So now if I'm pressed for time I'll make time and do it myself.

 

[BlackNBlue95]

My friend went to a oil change place and a couple of days later he asked me about his brakes, the pedal was very hard. I said that is usually from a bad power booster, they I asked him if he went to a oil change place, he said yes, I said I bet they put tranny fluid in your master. I heard of that before. Sure enough they did, he had to replace the whole brake system about $1500 and they wouldn't own up to itad

Lol sometimes it's not the shops fault... we had a customer come back after an oil change *****ing that we put brake fluid in here power steering resivior simply not true.. for one.. i think the pump was leaking at a seal or something I don't remmber exactly but our shop was closed when she had the problem so another shop looked at it and said yea someone probably put brake fluid in.. so she believed that and it was simply not true.. didn't even have to top off the resivoir on it either.. it was full to begin with.. i mean how do you prove that there is brake fluid or any fluid contamination for that matter? i know trans fluid is red.. so I'm not saying your brake story is un true be cause itmost likely is true.. that happens alot at lube joints.. where they have some half wit high schooler who never worked on cars before looking at a computer screen to see how many grease fittings there are.. and doesn't grease your new aftermarket tie rod end that has a fitting because from the factory it didn'thave one.. anyway thats my .02
-Rick

 

[Stallion]

"By removing the air filter one is effectively altering the fuel/air mixture ratio in the carb. A leaner (relativeley more air than fuel) mixture tends to increase Hp (all other factors being equal)."

Why would more air than fuel mean more hp? Wouldn't it be the other way around logically? If not, then why would people want a 4 or 6 barrel carb? Wouldnt' more fuel mean "bigger boom"?

Thanks!

TR

 

[MaineShark]

It's sort of like my recent brake problems after taking my Shark to the Chevy dealer for a new wheel bearing. Went to pick up the car, and the brakes were marginal, with the warning light lit up. I know it wasn't like that when I dropped it off, and they know it wasn't like that when I dropped it off, but they wouldn't admit to anything. They were oh so willing to sell me a new master cylinder, though.

Luckily, I smelled a rat, got some advice here to bleed the brakes, and have put over 100 miles on it since then with no trouble.

Stallion: the barrels are what the air flows through. The "jets" mentioned in a couple posts are what add the fuel to that air as it flows through the barrel. The reason for having a large number of barrels isn't to let more air in, though - one large barrel would do that. By splitting that one large barrel into several smaller ones, the fuel mixture is more evenly controlled (due to some aerodynamic laws). Tuned-port fuel injection basically takes this one step further, with one "barrel" (intake manifold runner) and one "jet" (fuel injector) for each cylinder.

Joe

 

[GerryLP]

Stallion,

That is a good question; generally speaking, 15 parts of air are needed for each part of fuel to attain the best fuel/air ratio for an automobile engine (that's about 9,000 Gallons of air for every gallon of fuel burned, or a more simple illustration would be 1/2 teaspoon of fuel for every cubic foot of air. :j

The weight (or mass) of the fuel has to be counterbalanced by the weight of the air, but since a cubic foot of air weighs approximately 1-1/4 onces and a cubic foot of fuel weighs approximately 775 onces, then we must compensate for the weight of fuel by multiplying the ideal rate of 15 to 1 by 620 (775 onces of fuel divided by 1-1/4 onces = 620), so by multiplying 15 times 620 we get 9,300 cubic feet of air needed to burn a cubic foot of fuel in an engine. Caloric value (the amount of heat released when burned) for the fuel also plays a role in this numer.

All things being equal, that 15 to 1 rate would change if the type of fuel was changed. If for example, a new type of fuel were to be discovered, and this new fuel would weigh less that gasoline, but it would also have a higher caloric value , then the rate would be more than 15 to 1.

 

[sscam69]

STallion

You can adjust the A/F ratio to do different things depending on what your goals are.

Obviously the big three set it up to try and pass emissions and somewhat for fuel economy. On the other hand when you start to shoot for more power at WOT you can adjust the A/F ratio to help you out. 15:1 ratio is the textbook A/F ratio. In a perfect world that would be the case, but the world is far from perfect.

The proper A/F ratio for the most power/torque depends on YOUR particular setup. Again that depends on the cam your running, heads, carb etc... On average though anywhere from 12.5:1-13:1 will give you the most power at WOT.

As the fuel gets richer (i.e. more fuel) the flame starts to burn hotter up to a point. After that the temp drops again and you also run into other problems. Because the flame gets hotter the heated air wants to expand more, i.e. more power.

Tuning a car can be a tedious task. But worth it if you are trying to get the most. As you can see in Gerrys case it made a BIG difference. When trying to measure the A/F on a chassis dyno make sure to ask if they have a WIDEBAD O2 sensor. This tells you what your A/F ratio is by testing the exhaust gases.

Frank

 

[BlackNBlue95]

STallion

You can adjust the A/F ratio to do different things depending on what your goals are.

Obviously the big three set it up to try and pass emissions and somewhat for fuel economy. On the other hand when you start to shoot for more power at WOT you can adjust the A/F ratio to help you out. 15:1 ratio is the textbook A/F ratio. In a perfect world that would be the case, but the world is far from perfect.

The proper A/F ratio for the most power/torque depends on YOUR particular setup. Again that depends on the cam your running, heads, carb etc... On average though anywhere from 12.5:1-13:1 will give you the most power at WOT.

As the fuel gets richer (i.e. more fuel) the flame starts to burn hotter up to a point. After that the temp drops again and you also run into other problems. Because the flame gets hotter the heated air wants to expand more, i.e. more power.

Tuning a car can be a tedious task. But worth it if you are trying to get the most. As you can see in Gerrys case it made a BIG difference. When trying to measure the A/F on a chassis dyno make sure to ask if they have a WIDEBAD O2 sensor. This tells you what your A/F ratio is by testing the exhaust gases.

Frank

Where can i learn more about the wideband 02's and how they work I vaguely remmber an instructor discussing these at an automotive seminar I went to about fuel control.. any websites or anything like that would be appreciated.. he was also talking (I was half asleep after work) about our 02's being basically a lambda switch.. and something about how the wideband varies amperage instead of voltage.. and somewhere a digital signal I dunno would like to know more though..

 

[smurfvet]

That's why I do as much as I can myself. I found a great suspension mechanic- he gets the alignment and front end work. I do the rest. I sleep better at night, and don't worry going into turn 1 at Watkins Glen at a high rate of speed.

 

[maxrevs85]

Acouple of months ago I bought my wife a 2000 Olds Intrigue. I put it in the garage and the next day backed it out to do a project. I then noticed oil on the floor . Found the oil plug loose . Four turns with the fingers and tightened with the wrench . I knew they had changed the oil and we were getting ready for a trip to Tenn, for thanksgiving ......oh yea btw, this car has a 140 speedo and traction control ,sport susp, 6500 redline , 3.5 dual overhead 24 v cam, leather and a host of other gooidies. Runs realy good. I grew up on Oldsmobiles , gonna miss them.

Have Merry Christmas everyone:SANTA
Dave