AFR gauge on your dyno? ( Westach ?)

regis101 · Post by **regis101** » Fri Apr 15, 2005 9:11 pm

Jake. Do you have a Westach or other analog type AFR gauge hooked up to yuor dyno? I'm wondering how the needle moves or sweeps when you find your final tune session for the customers engine at hand. I have a Westach unit on my stock 2.0 Westy. The only info I have is what westach states in their instructions. IIRC, they say that the more the needle moves back and forth from rich to lean, the better the engine is performing. Do you find this so? I can tune the stock FI to get the needle to move erraticly and lazily. When I lean it to the point that the needle is erratic, I loose power. When the needle is lazy, power is back, but gas mileage suffers. I have it tuned to a happy medium of power vs. gas mileage. Gas mileage is 17 combined. I think this was VW's number back in 78 anyway. I do not have info on the AFR's that use the LED's or are digital. Digital wouldn't be able to flucuate as cleanly as a needle type. If I apply Westach info to the LED style, the strip of lights should remind you of a Cylon warrior when things are right. Can ya offer any words? Thanks

Guest · Post by **Guest** » Sat Apr 16, 2005 7:10 am

Your air fuel gauge should have numbers on it. It doesn't matter how it sweeps. It should be around 12.5 to 1 full loaded and around 14 to 1 at idle and cruise.
Pushing the envelope and running 13's to 1 is not a good idea in a heavy bus under full load. That is an easy way to overheat the heads and drop a seat.

regis101 · Post by **regis101** » Sat Apr 16, 2005 7:33 am

13 's are on the rich side. 12.5 is supposed to be best for power. My observations while tuning allowed me to see both a lazy and erratic flucuation readings.

Guest · Post by **Guest** » Sat Apr 16, 2005 8:25 am

12.5 is richer than 13's. 13's are not enough fuel for a cool burn in the chamber. IT will get the heads hot. Keep in mind that the air fuel mixture is 50% of the cooling in an aircooled motor.

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Sat Apr 16, 2005 9:36 am

I have used a Westach as well as a couple of wide band arrangements that I had made for the purpose.

Now I use the LM-1 and its the best thing I have seen yet. It's very stable and responds quickly.

regis101 · Post by **regis101** » Sat Apr 16, 2005 3:28 pm

Thank you, guest. At least we're on the same side of richness. As it stands, the programming in my ECU makes the engine go full rich above 65mph which equates to 3400 rpm which equates more toward the high 11's. My real concern here is to find out how O2 sensor voltage response once again equates to peak engine performance across the board.

regis101 · Post by **regis101** » Sat Apr 16, 2005 3:30 pm

Jake. Maybe you could bend an eye at your AFR gauge during the dyno runs to see how the O2 sensor responds during the tuning sessions. I can tweak my FI to enable the gauge to fluctuate with throttle position. I know, I know, more crap to think about.

Volcano · Post by **Volcano** » Sun Apr 17, 2005 4:38 am

Regis,Please save the $ for the Inovate LM-1.I'd love to see you readjust your L-jet using the meter.The multibands are the only way to go.Besides,I want your data logs from your Bus.Regards,Roger

regis101 · Post by **regis101** » Sun Apr 17, 2005 7:34 am

Is that the newer hand held unit for ~$395? Wide band would be nice. How come yesterday just having an O2 sensor for tuning was the sh*t and today one needs a sniffer and a chassis dyno. It boggles the mind. I know you've been following any of my tuning posts. Where have ya been? I just can't keep my hands off the thing. Not trying to reinvent anything, just trying to figure out what the Bosch engineers were up to. I've almost come to the end of my tuning parameters on this one. Tne Westy is as good as it gonna get. I have three AFM's that I've been swapping around. Two are new rebuilds that I got the same day and one is my original. The two rebuilds make it run totally different from each other. One is lean and the other has great power but the mpg is <15. The lean one functions better between cold start and warm idle. The rich one is doggy from CS to WI. Go figure. Won't see that magical 20+ mpg although I did have a best of 20.5 on a road trip when all things were in my favor with the original one. I average 17 and that's what VW said back in the day and that's good enough for me. IMO, L-jet is good for what it is, and that's all. It's been fun tweakin'. On the bus that is.

Volcano · Post by **Volcano** » Mon Apr 18, 2005 4:22 am

Hi Regis,I know what you'r saying.I have 2 single bands.One from John at Aircooled & aAutometer instrument.Both are sort of fun but did'nt give me the info I wanted.The LM-1 shows that I need a 200 air correction as opposed to a 180.Oh,I have weber 44's in my bus.My friend has L-jet.It would be great to have an adicted tweeker like you feeding us info in real air fuel nos.The co. has great forums also.Talk to John at Aircooled.Best to you,Roger

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Mon Apr 18, 2005 7:14 am

I tune primarily from my Fuel Flowrator and EGT and use the LM-1 as a part throttle gauge of mixture only.

The LM-1 is much better with EFI tuning than it is for carb tuning.

regis101 · Post by **regis101** » Mon Apr 18, 2005 4:42 pm

I'll have to add addicted tweaker to my resume'. I am obsessed. probably to a fault. I'll research the wide band units.

Wally · Post by **Wally** » Tue Apr 19, 2005 12:55 am

MASSIVE TYPE IV wrote:I tune primarily from my Fuel Flowrator.

Jake,
Is this still possible with the return line that an EFI sytem uses?

Thanks,
Walter

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Tue Apr 19, 2005 7:30 am

Yes, but I have to use a special flowrator. I don't have one now but I have one being built....

Not cheap- about 2200 bucks!

dstar · Post by **dstar** » Tue Apr 19, 2005 7:40 am

Why don't you just flow what is actually GOING to the TBS,
not the whole line

Of course, that would take TWO Flowrators!

Don