ShopTalk Forums | Aircooled VW Tech & Restoration Help

You'll find that it won't rev very well at all till you get the fuel tables squared away, the fuel takes up space where more air should be.

Yea... I'm expecting to pick up some power after leaning things out. There was WAY too much fuel going into the engine.

I'll report back my findings tonight.

Tried out the leaned out table. Everything seems to work well. Pulls quite a bit harder than before. I did adjust the wastegate a little, but it was a small change compared to new fuel tables. I think the new found power is simply just from leaning out the mixture. I was WAY WAY too rich before. All in all, its now running more like I expected it to. Still won't rev out much due to the small cam, but pulls like a freight train right up to the limit.

My AFR gauge and MS still don't quite agree (they are off from each other by about 1pt, with the gauge showing richer), but they are much closer than before. I'll have to do some more investigating on that one.

Seemed to have gotten all the small oil leaks solved except for one little drip off the left hand valve cover. My newly installed crankcase breather lines seem to work nicely.

Is it off by 1 point .1 or .01?

So in Tuner Studio goto tools and make a special AFR calibration,

In the "Tools" menu goto "Calibrate AFR table" and for "EGO Sensor" choose "Custom Linear WB"

Set .5v as 10:1 and 4.5v as 20:1, with the ignition on hit "Write to Controller"

Hook up the LC1 and do the same through with it's software, that should make it dead on. Let me know the result.

So now that have leaned her out how is that duty cycle looking? Where did you end up putting your coolant temp sensor? Did it go in a valve cover? You motor is gunna love you for that breather. I constantly see oil in my breather lines, not sure if that is good or bad but I know it's working

MarioVelotta wrote:Is it off by 1 point .1 or .01?

So in Tuner Studio goto tools and make a special AFR calibration,

In the "Tools" menu goto "Calibrate AFR table" and for "EGO Sensor" choose "Custom Linear WB"

Set .5v as 10:1 and 4.5v as 20:1, with the ignition on hit "Write to Controller"

Hook up the LC1 and do the same through with it's software, that should make it dead on. Let me know the result.

So now that have leaned her out how is that duty cycle looking? Where did you end up putting your coolant temp sensor? Did it go in a valve cover? You motor is gunna love you for that breather. I constantly see oil in my breather lines, not sure if that is good or bad but I know it's working

I'm using the Default calibration for the LC-1 in Megatune which 0v=7.35 and 5v=22.05, which is the same as what the AFR gauge reads from. When my MS says 13:1, the gauge says 12:1. Theoretically they should show the same thing, as they are both using the same scale. I'll be looking into this further.

The duty cycle is looking a lot better. Now around 77% or so, and making much more power than before. Peak boost yesterday was 5.5lbs. The coolant temp sensor is in the left hand valve cover, and seems to be working pretty well there.

I'll be doing a lot more tweaking this weekend for sure.

The other odd thing is that I have some weird spikes in my data log. They don't appear to be the "classic tach spikes" I've read about on the Megamanual. Sometimes the speed shows way high, and sometimes it shows zero. All of the other parameters do the same thing too, just for a split second, then go back to normal. I'm wondering if they are resets or something, I didn't pay attention to the reset counter when I got back in last night. I'll be checking into this more too.

Those sound exactly like resets to me. I am currently completely rewiring my 60's EFI right now for exactly that reason. They drove me nuts, so I'm cutting out my hacked and spliced harness and built my own new one and am getting ready to get her installed as soon as the weather clears up. Do you have shielded wire on your VR signal? Thats one change that I'm doing this time around.

Magnetic suppression wires and resistor plugs will be required as well, if you don't already have them...

Yes I have shielded instrumentation wire for my VR sensor, and am using resistor plugs.

I think I may be overflowing my USB/serial adapter as that can happen according to the megamanual.

This is only the second time I've had the problem, usually its good. I don't think its my wiring, I'm more leaning towards the computer.

If you got your edis kit from boost you should have the resistor wires, did you use resistor plugs?

Wait- are you trying to talk to the wideband and MS at the same time? If so, I bet that's the problem...

MarioVelotta wrote:If you got your edis kit from boost you should have the resistor wires, did you use resistor plugs?

No.. I bought the EDIS kit from ebay, but all it came with was the factory Ford cables. They were too short, so I purchased some Accel wires and put the Ford ends and clips for the coil on them.

Yes, I'm using resistor plugs

miniman82 wrote:Wait- are you trying to talk to the wideband and MS at the same time? If so, I bet that's the problem...

No.. I'm only talking to MS.

I use the same serial adapter to set up MS and the gauge when the car is not running by switching it back and forth. When I'm running, the computer is only hooked up to MS with the serial adapter.

An update for today.. I think its solely a computer problem. I drove around today logging and didn't have any of the spikes or resets. I did however have my computer lock megatune up LOL. I think its just a computer thing.

Now, tonight I switched the MS over to 0v=10 and 5v=20 AFR in configurator, and then programmed the ouput on the wideband to the same scale, and the gauge and MS still reads wrong. It is closer now, but I'm still abound a 0.5-1 pt off. I think its purely inaccuracies in between the gauge and MS. Dunno...

None the less, its running well, and my max duty cycle is in the upper 70's. This means I COULD push a little more boost into it, but I think I'm going to refrain to take it easy on my crank. I'm chomping at the bit to get a forged crank and tear down the engine to build it up stronger. For now I'll just enjoy the car as is and hope that my cast cranks lives until then

Can you look at a log from the wideband, and an identical log from Megatune? Reason I ask is it may in fact be reading correctly, but the 'lag time' of MT might be causing you to read false readings. In other words if you see 14.7 AFR on the wideband readout, then see the same thing in your logs a second or so later...