Anyone experiment with high flow mufflers?

[ZugyNA]

Looks like it is a filter of some kind...so maybe the restricted exhaust is what increases the mpg. Wondering about the eventual need to clean it though.

"An additional key indicator that there is a net improvement in VE with the Blade is the fact that the throttle position (TP) angle is 10% higher than it is without the Blade at the same engine speed. The TP increase signifies a decrease in “pumping loss”, which means that there is less effort required for the piston to pull air into the combustion chamber. The reduced pumping loss is attributed to the Blade’s effect of reducing space between the exhaust pulses. Normally, a degree of “backsliding”, exhaust being pulled back into the combustion chamber during “induction”, occurs. The Blade's affect reduces the space between exhaust pulses. This results in less “backsliding”. Less backsliding increases the amount of clean air into the combustion chamber thus increasing Volumetric Efficiency. There is a direct correlation between reduced pumping loss and increased engine efficiency."

So you either reduce backpressure (spiral core) or you increase it (filter or valve)....

So take a tin can...put a hole in it smaller than your tail pipe...clamp it solidly on the exhaust and go test it?

For instance...a 60 HP engine only needs ~ a 1.1" ID exhaust...believe it or not.

60HP (at the crank) per square inch of (cross-sectional) flow area needed

PI*r2

Got 90 HP? Need 1.5 square inch flow area or 1.4" ID?

Hope I got this right....

[ZugyNA]

Originally Posted by slurp812

I have this

http://www.gassavers.org/garage_imag...ry1wxmulun.jpg

I had nothing but a fiberglass filled exhaust tip and a cat on a 3L V6 and it was the best sound I've heard on a car I've owned. Much better than a glasspack muffler. Problem is it rusted out after 3 yrs or so.

[trebuchet03]

Originally Posted by omgwtfbyobbq

I wouldn't go as far as to say it's valid if they're comparing a car w/ 40k miles on it and who knows what in/on the crankcase/gearbox/wheels to whatever the EPA used to test. Weren't these the guys who said driving around at different dates/times in one of the most traffic ridden areas in CA was a legit version of the EPA test? I smell bull...

Iono, can you link us up to the traffic thing? That would be pretty bad

According to the company they used (http://www.automotivetesting.com/home.htm), they are a CARB certified (or whatever the term is) facility - and the EPA lists them as a suitable facility...

A second (and even third) test would be nice... but looks like we'll have to wait at least a year for that.

One thing they have going for them... I don't see any testimonials on their website... A bonus... It also looks like this originates from out of the country (Brazil?) with a spin off in the US...

[CoyoteX]

Originally Posted by ZugyNA

So take a tin can...put a hole in it smaller than your tail pipe...clamp it solidly on the exhaust and go test it?

I tried this with my Camaro. I made some covers that went over the square exhaust tips with a 1 inch hole in them. The car normally has a very horrible idle and you can't stand near the back of the car because of the fumes but with those covers on it was a lot better. It has a camshaft with 110 degree lobe separation so it dumps a lot of unburned gas out the exhaust at idle because of the overlap. They got blown off the exhaust when I started driving it though so I have no idea if they helped mileage or not. I kept meaning to make another set and clamp them on a lot tighter but I haven't drove that car much lately and kind of forgot about it.

I do think that reducting the exhaust flow will help mileage on the low end and probably kill your power and mileage on the top end. Even a car with a mild cam still has some overlap so it is possible to pull some of the intake charge out the exhaust without using it for the combustion if the exhaust has good velocity. Also by restricting the exhaust you are keeping the cylinder from getting rid of all the exhaust and some of it remains in the cylinder so it is kind of like what the egr does and might help reduce pumping losses that way.

[cfg83]

Coyote X -

Originally Posted by Coyote X

I tried this with my Camaro. I made some covers that went over the square exhaust tips with a 1 inch hole in them. The car normally has a very horrible idle and you can't stand near the back of the car because of the fumes but with those covers on it was a lot better. It has a camshaft with 110 degree lobe separation so it dumps a lot of unburned gas out the exhaust at idle because of the overlap. They got blown off the exhaust when I started driving it though so I have no idea if they helped mileage or not. I kept meaning to make another set and clamp them on a lot tighter but I haven't drove that car much lately and kind of forgot about it.

I do think that reducting the exhaust flow will help mileage on the low end and probably kill your power and mileage on the top end. Even a car with a mild cam still has some overlap so it is possible to pull some of the intake charge out the exhaust without using it for the combustion if the exhaust has good velocity. Also by restricting the exhaust you are keeping the cylinder from getting rid of all the exhaust and some of it remains in the cylinder so it is kind of like what the egr does and might help reduce pumping losses that way.

That's what this thread made me think of doing. You could have different sized openings for testing.

Ha ha, now I am thinking of using cookie press patterns :

Attachment 1035

Do you think these metal (tin? aluminum?) patterns would hold up to the exhaust heat?

Maybe I could use the X-Mas tree pattern for December, .

CarloSW2

[omgwtfbyobbq]

Originally Posted by trebuchet03

Iono, can you link us up to the traffic thing? That would be pretty bad

Ecocleanfuel! The wave of the future. Because driving around city streets at different times/days is a very valid test technique.

Does this sound familiar?

This product is a proven fuel saver for Gasoline and Diesel engines while simultaneously reducing tail pipe emissions. Third party independent testing in strict accordance with the SAE TYPE II J1321, EPA 511 (including FTT75), CFR 86 and California Title test protocols for fuel savings and emissions to EPA and CARB standards.

And here's(Dead link, just google the second paragraph for other similar claims for similar websites, or go to ecocleanfuel.org which is redirected to eyicom.com) a write up on the test.

The vehicles are run over the course at the same time with the drivers endeavoring to remain in sight of one another and to start and stop the vehicles simultaneously.

During the test, ATDS drivers drove both cars over a real-world road route in the Ontario, CA. area of approximately 54 miles in length. Depending upon traffic conditions the vehicles were able to complete either 2 or 3 laps prior to returning to ATDS for fuel measurement and refill.

Unless on a dyno and involves a strict driving schedule, or on a closed test track at some cruising speed, I'm not very inclined to accept the validity of any of these tests.

[trebuchet03]

Originally Posted by omgwtfbyobbq

Ecocleanfuel! The wave of the future. Because driving around city streets at different times/days is a very valid test technique.

...


Unless on a dyno and involves a strict driving schedule, or on a closed test track at some cruising speed, I'm not very inclined to accept the validity of any of these tests.

Yeah... that's pretty bad... But it would seem to be a different company all together. We could contact the testing facility to be sure (the stuff in that thread doesn't seem to provide who the "Third party independent" tester was)...

[omgwtfbyobbq]

Different company, same tester, kinda suspicious imo. Could be the same group coordinating this stuff, but who knows?

P.S. It helps with erectile dysfunction and baldness too!
*looks for pic of monkey from idiocracy*

[cfg83]

omgwtfbyobbq -

Originally Posted by omgwtfbyobbq

Different company, same tester, kinda suspicious imo. Could be the same group coordinating this stuff, but who knows?

P.S. It helps with erectile dysfunction and baldness too!
*looks for pic of monkey from idiocracy*

Yes, for the Vornado (and fuel magnet?) style gizmos, I seem to remember that there was a person in Northern California that ran a public utilities truck fleet. This manager was named more than once for more than one MPG product.

Oh well,

CarloSW2

[trebuchet03]

Originally Posted by omgwtfbyobbq

Different company, same tester, kinda suspicious imo. Could be the same group coordinating this stuff, but who knows?

P.S. It helps with erectile dysfunction and baldness too!
*looks for pic of monkey from idiocracy*

I totally missed the second page of that thread! Sorry about that - that's where all the juicy bits were. Not only suspicious, but total destruction of that facility's credit.

Bugger for them.... In any case, extra back pressure may still be a good experiment to explore (the dough extrusion thingers look pretty cool)