µSquirt ( microSquirt ) powered Vanagon ramblings

Bus, Microbus, Transporter, Station Wagon, Vanagon, Camper, Pick-Up.

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chewabledrapery
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Re: µSquirt ( microSquirt ) powered Vanagon ramblings

Post by chewabledrapery » Thu Apr 21, 2016 11:54 pm

Hi,

Thanks for the comments!

I didn't really "science" my choice of Fast Idle valve as much as i should have and just bought a few cheap ones from ebay until i found one that seemed like it would do the job, sadly there just aren't that many junkyards these days where i could just go and have a rummage so I used google images and ebay, I did wantto use the one you have but couldn't track one down in the UK.

I tried 2 other junk valves, one from a VW Jetta that was way too restrictive and still let air a bit of air though when closed, and one from a suzuki bike that was normally open rather than normally closed so that was unsuitable too.

Stupidly I didn't actually measure the ID of this valve but I'm pretty sure it wasn't too far off the original L-Jet AAV as I had previously discarded the VW Jetta solenoid valve for being too restrictive... (I think I actually sucked on the solenoid valves and then original AAV to feel how much air was coming through when open!! not particularly scientific!!)

The one I ended up using was from a Mercedes E240 I think I paid about £5 for it although they do sell for a lot more, p/n is 0004701593

I've found a link to it here http://www.everythingbenz.com/z/part/00 ... -egr-valve

Cheers.
76 Bay, 2.0L Megasquirted and converted from auto to manual transmission.

luftvagon
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Re: µSquirt ( microSquirt ) powered Vanagon ramblings

Post by luftvagon » Fri Apr 22, 2016 6:34 am

Thanks for that. That looks like it would work very well. The way I have my fast-idle configured is by using FIDLE output, and using programmable on/off output.

FIDLE
[x] Enabled
Power On Value: OFF
Active Value: ON
Active Conditions:
output channel: seconds < 25.0 (threshold) 0.0 (hysteresis)
OR
output channel: coolant < 110.0 (threshold) 5.0 (hysteresis)

This will give me 25 seconds of fast-idle on power-on, or until engine temperature reaches 110F.
Ideally, you would want that number to be around 5 seconds, or until whatever pre-determined temperature it is before you can control idle using timing.

Looking forward to corroborating with you, and learning from your experience.
1981 Volkswagen Vanagon Westfalia - air-cooled Type4 1970cc CV (hydraulic lifters, 42x36 valves, stock cam, microSquirt FI with wasted spark ignition)
1993 Ford F-250 XL LWB Extended Cab 7.3L IDI

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Re: µSquirt ( microSquirt ) powered Vanagon ramblings

Post by luftvagon » Fri Apr 22, 2016 6:49 am

and I just ordered a Mercedes purge valve 0004701593. Can't wait to try it. Sad to say my van has been sitting since November last year with just too many other projects in the way, and not enough time to go camping or do anything.
1981 Volkswagen Vanagon Westfalia - air-cooled Type4 1970cc CV (hydraulic lifters, 42x36 valves, stock cam, microSquirt FI with wasted spark ignition)
1993 Ford F-250 XL LWB Extended Cab 7.3L IDI

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chewabledrapery
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Re: µSquirt ( microSquirt ) powered Vanagon ramblings

Post by chewabledrapery » Mon Apr 25, 2016 2:01 am

luftvagon wrote:and I just ordered a Mercedes purge valve 0004701593. Can't wait to try it. Sad to say my van has been sitting since November last year with just too many other projects in the way, and not enough time to go camping or do anything.
Hey, no problem I hope the valve works out for you and thanks for the idle settings I'll give these a go too once I'm back under the bus.

Yes I'm sad to say that in the 10 years since I've had my bay I've probably used it to go camping 5 times as it has constantly broken down due to engine failure but the main recurring problem I've had over the years was I had drive plates breaking after a 1000 miles or so.

This was the driving factor in doing the engine rebuild and megasquirt, I want to know what is going on under the hood, and as I say the main problem I had was the automatic drive plate failing literally every summer it must have been a faulty torque convertor or something but there just aren't many auto buses in the UK so no there are no experts in the field (and believe me I tried to find them over the years) so I took the drastic route of converting to manual.

Really can't wait to get on the road this summer, I've got a good feeling about the modifications I've done and I have the power to control my own destiny and really understand the bus/engine/transmission top to bottom, I really want to use the bus and go camping and kick back by the coast etc. etc. without worrying that I'm going to lose my transmission after a 200 mile trip, or have some part of the aging L-jet system fail on me.

By the way I'm not bashing the original VW system I know they did and can work very well I just wanted something that I could be "master" of.

I'm also looking forward to collaborating thank you so much for the advice thus far

I'll report back once I get under the bus again!

Deano.
76 Bay, 2.0L Megasquirted and converted from auto to manual transmission.

luftvagon
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Location: Little Rock, AR
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Re: µSquirt ( microSquirt ) powered Vanagon ramblings

Post by luftvagon » Mon Apr 25, 2016 4:02 pm

Mercedes part is in. The opening looks like it would fit the bill. The original L-Jetronic is best they could've made, back in the late sixties. microsquirt or megasquirt solution is a great way to be more intimate with your engine, without being #vw_type_4_whisperer_aka_colin.
1981 Volkswagen Vanagon Westfalia - air-cooled Type4 1970cc CV (hydraulic lifters, 42x36 valves, stock cam, microSquirt FI with wasted spark ignition)
1993 Ford F-250 XL LWB Extended Cab 7.3L IDI

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Re: µSquirt ( microSquirt ) powered Vanagon ramblings

Post by luftvagon » Sun May 01, 2016 11:59 am

Got the part installed. Only got about 25 RPM more, or so.
1981 Volkswagen Vanagon Westfalia - air-cooled Type4 1970cc CV (hydraulic lifters, 42x36 valves, stock cam, microSquirt FI with wasted spark ignition)
1993 Ford F-250 XL LWB Extended Cab 7.3L IDI

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chewabledrapery
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Re: µSquirt ( microSquirt ) powered Vanagon ramblings

Post by chewabledrapery » Sun May 01, 2016 12:38 pm

Ah. OK. Hope I haven't wasted your time!
76 Bay, 2.0L Megasquirted and converted from auto to manual transmission.

luftvagon
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Location: Little Rock, AR
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Re: µSquirt ( microSquirt ) powered Vanagon ramblings

Post by luftvagon » Sun May 01, 2016 7:16 pm

Nope, it's good. It's 25 more than I had... The next trick up my sleeve is to rise or lower the idle timing a bit. i think it's about 12.7 at the moment, and my cold-start AFR mixture is about 11.5 to 12.0. Don't know if I should crank it past that.
1981 Volkswagen Vanagon Westfalia - air-cooled Type4 1970cc CV (hydraulic lifters, 42x36 valves, stock cam, microSquirt FI with wasted spark ignition)
1993 Ford F-250 XL LWB Extended Cab 7.3L IDI

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Amskeptic
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Re: µSquirt ( microSquirt ) powered Vanagon ramblings

Post by Amskeptic » Sun May 08, 2016 7:47 am

luftvagon wrote:Nope, it's good. It's 25 more than I had... The next trick up my sleeve is to rise or lower the idle timing a bit. i think it's about 12.7 at the moment, and my cold-start AFR mixture is about 11.5 to 12.0. Don't know if I should crank it past that.
VW had a damn fine trick with idle timing on cold late-carbureted bus engines.

They took the vacuum retard signal off the throttle body just below the throttle plate. When the chokes were on, the fast idle links tipped the plate edge past the vacuum retard so no vacuum retard + higher idle speed would involve the centrifugal advance weights.

The overall difference in timing would be 10* ATDC normal idle timing.
16*BTDC timing during choke operation.

Both of you feel free to play with timing so long as it reverts to normal at operating temperature.
You might find 15* BTDC wakes up the auxiliary air regulators a bit better.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

luftvagon
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Re: µSquirt ( microSquirt ) powered Vanagon ramblings

Post by luftvagon » Sun May 08, 2016 6:39 pm

Good idea Colin. My timing is very conservative at the moment, and I will just add extra 4 degrees BTDC until the engine reaches ~100F. This would give me 15-16BTDC at idle, until desired temperature. My "AAR" is fully open until 110F, and then it shuts off completely (On/Off operation/no gradual closure). My total advance would be 30 BTDC @ 3900 RPM until 110F, and then it would go back down to 26 BTDC. I could even add additional 2 degrees across the board, for a total 28 BTDC @3900. I run 91 octane most of the time. So many options. :)
1981 Volkswagen Vanagon Westfalia - air-cooled Type4 1970cc CV (hydraulic lifters, 42x36 valves, stock cam, microSquirt FI with wasted spark ignition)
1993 Ford F-250 XL LWB Extended Cab 7.3L IDI

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Re: µSquirt ( microSquirt ) powered Vanagon ramblings

Post by luftvagon » Sun May 08, 2016 7:39 pm

Something else just dawned on me... I based my "SVDA" timing using these charts:

Image

Image

Is it just me or does anyone else think these are bit off?

If you take SVDA for an example, and you set your "max" timing to 32 @ 3000 RPM, that means you have about 14.5 degrees of initial timing, with a maximum timing of 38.5 @ 4000 RPM. Does that sound correct, or am I reading this chart incorrectly.
1981 Volkswagen Vanagon Westfalia - air-cooled Type4 1970cc CV (hydraulic lifters, 42x36 valves, stock cam, microSquirt FI with wasted spark ignition)
1993 Ford F-250 XL LWB Extended Cab 7.3L IDI

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Amskeptic
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Re: µSquirt ( microSquirt ) powered Vanagon ramblings

Post by Amskeptic » Mon May 09, 2016 5:13 am

luftvagon wrote: If you take SVDA for an example, and you set your "max" timing to 32 @ 3000 RPM, that means you have about 14.5 degrees of initial timing, with a maximum timing of 38.5 @ 4000 RPM. Does that sound correct, or am I reading this chart incorrectly.
People get tangled up in this all the time.

The "0" on the chart is merely "not advancing yet". The max number is the "totally advanced". That means the chart shows only the range and progression of the centrifugal or vacuum advance unit charted.

YOU determine the initial position (or in our case, the maximum position).

All of the charted distributors in your graph above start at a graphed "0" position. On the engine, they start usually around 7.5* BTDC down to 0*BTDC. If you added the charted 25* maximum advance to an initial timing of 7.5*, you would think that you are allowed 32.5*BTDC maximum advance on the engine. We set the maximum advance on the engine to the clearly delineated 25-28* cut-out on the factory delivered on the scale. That usually gives us an idle timing of 7.5* on a new distributor and 3-4* BTDC on an older distributor.

With the vacuum advance factored in, yes, 38.5 to 40* on throttle overrun is fine.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

luftvagon
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Location: Little Rock, AR
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Re: µSquirt ( microSquirt ) powered Vanagon ramblings

Post by luftvagon » Mon May 09, 2016 10:42 am

Hey Colin, thanks for chiming in. I did factor in the initial "advance". I was shooting for 32 BTDC @ 3000 RPM; which would yield initial offset of 12 degrees.
With that said, according to the graph, the max timing would be ~36 BTDC @ 4000 RPM, and not on over-run. My engine will take XXX BTDC on overrun with fuel off ;) but it will also take 50 BTDC on high rpm and high vacuum (PART TROTTLE/NO TROTTLE). I sent an email to Ratwell to see how he measured this advance vs. RPM.

I remember, several years back, when you and I set my timing with the SVDA, the aircooled.net SVDA would not mechanically advance past 3200 RPM. That was its mechanical limit.

Which brings me back around, maybe I just had a crappy SVDA that would not mechanically advance past 3200 RPM. My understanding may have been flawed. I thought SVDA would not advance past 3200 RPM, and it may have been because of the unit I had.

Thoughs? What do you think would be the safest "mechnical" advance at, lets say 4000 RPM. We know 36 BTDC is what a "good" and well broken-in SVDA could give us. How about 5000 RPM?

#trying_to_blow_her_up
1981 Volkswagen Vanagon Westfalia - air-cooled Type4 1970cc CV (hydraulic lifters, 42x36 valves, stock cam, microSquirt FI with wasted spark ignition)
1993 Ford F-250 XL LWB Extended Cab 7.3L IDI

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chewabledrapery
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Re: µSquirt ( microSquirt ) powered Vanagon ramblings

Post by chewabledrapery » Tue May 10, 2016 6:23 am

Hoping to actually have some time to play with mine this weekend! Will let you know how i get on :)
76 Bay, 2.0L Megasquirted and converted from auto to manual transmission.

luftvagon
Old School!
Location: Little Rock, AR
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Re: µSquirt ( microSquirt ) powered Vanagon ramblings

Post by luftvagon » Tue May 10, 2016 7:48 am

I'll have an updated timing map for you. Worked on it last night -- basically +12 degrees across the map, with a taper down on closed throttle. Looks very good, hoping it drives good.
1981 Volkswagen Vanagon Westfalia - air-cooled Type4 1970cc CV (hydraulic lifters, 42x36 valves, stock cam, microSquirt FI with wasted spark ignition)
1993 Ford F-250 XL LWB Extended Cab 7.3L IDI

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