Wideband Results

[millerje78]

great thread!
_________________
always seeking a better way
my 73 standard project

do your research, consult with experts, and buy quality parts. you won't be sorry

[DubKru]

I agree! Great thread!

I also agree that buying your own wideband is a good investment. I got the lm-1 with auxbox and i've used it to tune two vehicles so far. And you can charge folks a small fee to get their stuff right.
_________________
2L, Raby cam, HAM Heads, Mallory, Dual Dell 40's, Porsche discs, Fuchs (Colored matched not to my bus),tunin' the crap out of it, slammed on Wagenswest suspension.

[Arnolds64]

My 2017 with a 110Engle, 043 heads has been running warm as well and I been running about the same setup- 50/140/200. I do however have 34 vents which I closer to what John a AC.net says in relation to valve size and vent in his article. My heat is due to .090 deck which I am working on right now.

I have a narrow ban which I know is not as accurate but it's better than nothing. Your setup should be pretty much the same for me. This is very helpful!
_________________
64 Bug, White, 2017, Dual Weber 44's, Engle 130/Engle lifters, Home P&P'd 40X35 heads, CB 4340 nitrided crank, Eagle knock off H Beam 5.5" rods, Lowering Beam, Rancho Trans, Traction Bar. 225X60's rear, 145's front on Porsche Chrome Nipple Wheels.

[nikita]

[Bad bug]

Glen i am suggesting that these post be made into a sticky, can really help people like myself when the time comes to tune my engine. I also bought an LM1 with auxbox to tune my engine, can't wait to get started.

[[email protected]]

I'm an idiot, ignore me, everyone else does (and runs 13:1 all the time, MORONS).

For those that are interested in knowing, if you keep leaning out the engine the engine will run cooler and cooler as power is dropping off, until the engine just dies since combustion will not occur with too lean a mixture. Only airplane guys have a clue on ROP and LOP tuning. I'm an engineer that reads too much. The automotive guys are 40 years behind the times. Most guys would just stare at you if you told them (and were correct) that 15:1 runs cooler than 14:1, and 16:1 runs cooler than 15:1, etc.

The problem is guys that know just a little bit, and think they know a lot. These are the guys that will tell you to run "32 degrees of total timing" for example. With that much timing, you have to run a richer mixture for the engine to get out of it's own way. There are only 3 guys I know of that TRULY understand that ignition timing and A/F are not independent of one another. The problem is they are ADJUSTED independently, but their affect on one another is dramatic, and guys do not get it.

Most guys set the timing to 30-32 total, then tune the WOT to produce best power. All they have done is found best A/F for THAT timing. In fact, most engines will make MORE power and run clean if you'd lean it out, and pull out some timing. You have to follow an iterative process to find the sweet spot. Find A/F, set timing, find A/F, set timing, Find A/F, etc. Most guys are so rich they have to run a lot of timing, since the burn happens so slowly because it's so fat. But they don't see that they'd need less fuel IF they'd run less timing, since "all motors make more power with more timing". This can be seen on your engine if you run super rich (like 10:1), you need to run WAY too much timing (another 10 degrees), but it will actually run "OK" and you wouldn't know it was so far out of tune by how it ran. But if you can convince them (which is difficult/impossible most of the time, because they are tuning the wrong way) to lean and retard, the engine wakes up!

An example of being properly tuned is seen with that guy in San Francisco in a recent thread with his IDFs (edit: oh yeah, that's THIS THREAD LOL).

When he started getting close running a LEAN cruise, he had to pull out ignition timing, which allows him to run leaner still, and maybe pull out even more timing. That sucker is going to run cool and return some fantastic MPG when he's finished. I think 40mpg is not difficult, but some "experts" talk like 25mpg is the Holy Grail or something, when in fact it's a joke.

Hopefully the average Joe will have a clue on tuning in 10 years, just like the average Joe NOW is not 009 brainwashed, at least not like they were a decade ago.

John
Aircooled.Net Inc.
_________________
Please do NOT send me Private Messages through the Samba PM System (I will not see them). Send me an e-mail to john at aircooled dot net

"Like" our Facebook page at
http://www.facebook.com/vwpartsaircoolednet
and get a 5% off code for use on one order for VW Parts ON THE NEW WEBSITE, vwparts.aircooled.net

[Bad bug]

John i don't think you are an idiot. I do know that by making your mixture leaner you will have good gas mileage but i wasn't sure of what to do with timing. I will be building my engine sometime soon as i no more trust anyone to doing this job. I also bought some tools to help me with the building of my engine cc head kit, lm1 with auxbox etc, etc. I really do hope that you guys can help me when the time comes.

[74 Thing]

What is ROP and LOP stand for? Is it for rich and lean of hte stoichiometric ratio of 14.7:1?

John-how do you fine tune the idle jets? I understand the mains and airs at WOT, but the idle do you just go down until you are in the 14's at idle and in the 16's when just off idle?

Thanks

[wheel607]

"Covington and Foust" John, you have got to be kidding.

[[email protected]]

I have to go see the Dr right now, I'll elaborate further later for those interested.

Covington and Foust is a quote from Mario Gavazzi. Google him.

ROP = Rich Of Peak (EGT)
LOP = Lean Of Peak (EGT).

peak being stoic! If you want to run hottest run 14.4:1.

John
Aircooled.Net Inc.
_________________
Please do NOT send me Private Messages through the Samba PM System (I will not see them). Send me an e-mail to john at aircooled dot net

"Like" our Facebook page at
http://www.facebook.com/vwpartsaircoolednet
and get a 5% off code for use on one order for VW Parts ON THE NEW WEBSITE, vwparts.aircooled.net

[redbluebug]

[nikita]

This chart helps explain ROP and LOP.



Note that maximum power and highest Cylinder Head Temperature both result from a slightly rich mixture.

1/Brake Specific Fuel Consumption is fuel efficiency and it peaks at a slightly lean mixture. Note the much lower, and safer, CHT.

ICP=Internal Cylinder Pressure (peak).

[74 Thing]

That is an interesting graph. What does the bottom line represent?

By the data on the graph it indicates that the leaner you run the cooler everything will be but you will lose HP. I would think that there is a point where it would be too lean to run-what are the signs of reaching that point?

PS-very informative thread.

[[email protected]]

DON'T CONFUSE PEOPLE WITH THE FACTS!!!

The bottom line on that graph in a nutshell is engine efficiency. Power from fuel used. Ideally your gearing would be such that you were at the peak of that curved line (1/BSFC) at your cruising speed. Note that this point is 50F COOLER than peak EGT, and it's also leaner than stoic (1 Lambda = 14.4:1 on gas).

So why are the Muppets running 13:1 at cruise and bragging about it?????

Note that once you hit Stoic, the leaner you go the cooler the engine runs. BUT, there is a point of diminishing returns, since you have to use more pedal (and more fuel) to regain power that you lost by being lean. There is a point where if you lean out more your MPG will go DOWN (1/BSFC is decreasing, sloping down), since efficiency is decreasing. But note that the area at the top of the 1/BSFC curve is very flat, you have a good deal of room to play around (tune) with. You want to target the peak of that 1/BSFC curve for max MPG. And surprise surprise it runs cool. DUH

This info has only been around for a short period of time, like 75 years.....

John
Aircooled.Net Inc.

[74 Thing]

John,

Can you touch on more how to jet the idle circuit? Is it best to pull the main jet stack and then make pulls on only the idle circuit to see where you stand? Thanks

[BugUser]

[[email protected]]

yeah, but insignificant. My memory is not what it used to be, I tune with Lambda not A/F so it doesn't matter to me enough to get the #s right LOL

John

[[email protected]]

that's how I do it. Then I jet the main circuit way TOO RICH, so when it comes in you see when. Then you tune it to come in at the right TIME, since it's too rich you can see exactly when it's coming in.


Then you jet it to the right amount to fix being too rich. But thats how I do it.

John
Aircooled.Net Inc.

[Bad bug]

Glen i am asking that this thread be made into a sticky. Too much good info here.

[[email protected]]

I also feel that tuning by A/F is a bad idea because the Stoic depends on the fuel used. IOW, it's different for all the gas/ethanol combos everyone is having to face nowadays. THAT is why your engine can be tuned fine now, and then all of a sudden run like chit when they make a fuel change on you.

I like BP, Mobil, Exxon.

John
Aircooled.Net Inc.
_________________
Please do NOT send me Private Messages through the Samba PM System (I will not see them). Send me an e-mail to john at aircooled dot net

"Like" our Facebook page at
http://www.facebook.com/vwpartsaircoolednet
and get a 5% off code for use on one order for VW Parts ON THE NEW WEBSITE, vwparts.aircooled.net