µSquirt ( microSquirt ) powered Vanagon ramblings

[luftvagon]

I've made a few videos today, and a few pictures.



http://www.youtube.com/watch?v=S2dFWLI9BeQ

Uploading the videos you guys requested at the moment.

[luftvagon]

Warm Idle:
http://www.youtube.com/watch?v=9LxGkXodzxQ

Fully warmed up engine:
http://www.youtube.com/watch?v=-qktTjtGJMk

AFM
http://www.youtube.com/watch?v=7GEJpxsgsq8

[airkooledchris]

at first I thought it sounded pretty damn good, but that noise as you rev UP the engine when fully warm is unnerving. something knock knock knocking on rebuilds door me thinks, but hopefully someone with more experience will chime in to say for sure what it is.

other than that sound the engine sounds pretty happy. could use a little cleaning/dusting, but otherwise looks good and all in place.

[Amskeptic]

I've made a few videos today,

OK, we have the fully warm engine video, but are still missing the high rpm float test.
You are revving the engine only off-idle, and with the lousy fidelity of you-tube and my computer speakers, I am going to give only a guess that you have a collapsed piston skirt, or a rod bearing.
Tear it down and have fun.
Colin

[luftvagon]

Colin, thanks for the input. I may have not posted the correct video. In one video, I am holding it at 3k RPM, abruptly letting go of the throttle, and immediately going back to 3k RPM. There is a nasty knock knock knock, until we get to 3k RPM.

Does one even need 42mm x 36mm head, and mild cam? I will be towing a small trailer and my dual sport motorcycle, and want this thing to last me. Should I even be considering it?

I am really tempted to order that engine budget engine with OE specs, because I cant build it under $5000.

[SlowLane]

I will be towing a small trailer and my dual sport motorcycle, and want this thing to last me. Should I even be considering it?

In my opinion, no. The aircooled engines are plenty stressed just pushing the Vanagon around (esp. the Westfalia). Asking it to perform towing duties will only shorten its life further.

Having gone through the experience of rebuilding my own engine (after the AVP engine I had installed just a few years ealier dropped a valve seat with only 25,000 km on it), I wouldn't recommend the experience unless you have a lot of time and patience. The problem is finding quality parts and not succumbing to the temptation to use more readily available inferior parts (main bearings being a good example).

Since you:
1) Don't have an emotional attachment to the '81 (my personal Achille's heel)
2) Have a need to tow something.
3) Have a reasonably-priced option in the '85
I'd say go for the '85, but keep in mind they have their issues as well (but it sounds like you're aware of that already).

Unless you suffer from the same peculiar brand of air-cooled masochism that the rest of us do...

[luftvagon]

A little bit of masochism is good for you... It lets you know you are alive. Another occasional extra 400lb (trailer + bike) may not be good, but its not like I am doing it all the time. We are talking maybe 1 or 2 trips around Arkansas. The highest hill we have here is 2200 feet.. and usually I won't be driving this for more than 100 miles with a trailer.

Now all I have to decide is which company to go with and if i should go with mild-cam upgrade, and 42x36mm; or stick with stock, and hydraulic lifters. Not wanting to start debates of what is better, I'd like to know the facts.

Here is what I have been told before:
Hydraulic Valves have higher interval before adjustments, or don't need adjustment.
You sacrifice power after 4000RPM.

Mechanical Valves require maintenance at XXXX miles, but don't usually go out of adjustment.
You don't lose any power past 4000RPM.

What else should I know about each?

Should I stick with OE spec motor with hydraulic valves?
or, go with OE motor with mechanical valves?

Or, get the upgraded head with new AMC cast heads and 42x36mm stainless steel valves, and stiffer springs?

[Amskeptic]

Here is what I have been told:

A) Hydraulic Valves have higher interval before adjustments, or don't need adjustment.
You sacrifice power after 4000RPM. Mechanical Valves require maintenance at XXXX miles, but don't usually go out of adjustment.
You don't lose any power past 4000RPM.

B) get the upgraded head with new AMC cast heads and 42x36mm stainless steel valves and stiffer springs?

A) Hydraulic valve trains are absolutely fine in a stock application. They get upset further up the band. They are superior down in our rev band for the simple reason that they are nicer to valve stems. I do not subscribe to the notion that they are "more maintenance free". I think it is a good idea to get under the car and check things out every oil change.

B) If you did not specifically ask for larger valves and stiffer springs for your specific reasons, then I doubt very much that you would ever be able to tell in normal driving. You will be able to tell right away, however, that your fuel injection system is annoyed with you if you should "upgrade" your camshaft. What larger sizes do for people who ask, is to help the engine breathe up past 4,000 rpm. They also destroy the vacuum signature for the FI at idle, giving you lousy idles, lousy cold starts, and sometimes finicky transitions.

People get all excited about the "heavy Vanagon" and how much harder it is on the engine, and I must share the fact that on the highway, the Vanagon is easier on the engine because of its superior aerodynamics. On hills, big deal! The damn thing weighs no more than 250lbs more than a bus. People bring a hefty friend along in a bay, and that is the entire Vanagon weight penalty there, nobody is complaining that bringing a friend and the dog is blowing up the engine. As a matter of fact, I see well-lived-in buses every day that are carrying around an additional 300 lbs of crap. They are designed to carry a ton of cargo.

Keep your Vanagon's engine *clean where it counts*, well maintained, and drive it like you are not in some stupid hurry, and it will do fine ... after you have performed a thorough high quality overhaul. We can help.
Colin

[Bleyseng]

A little bit of masochism is good for you... It lets you know you are alive. Another occasional extra 400lb (trailer + bike) may not be good, but its not like I am doing it all the time. We are talking maybe 1 or 2 trips around Arkansas. The highest hill we have here is 2200 feet.. and usually I won't be driving this for more than 100 miles with a trailer.

Now all I have to decide is which company to go with and if i should go with mild-cam upgrade, and 42x36mm; or stick with stock, and hydraulic lifters. Not wanting to start debates of what is better, I'd like to know the facts.

Here is what I have been told before:
Hydraulic Valves have higher interval before adjustments, or don't need adjustment.
You sacrifice power after 4000RPM.

Mechanical Valves require maintenance at XXXX miles, but don't usually go out of adjustment.
You don't lose any power past 4000RPM.

What else should I know about each?

Should I stick with OE spec motor with hydraulic valves?
or, go with OE motor with mechanical valves?

Or, get the upgraded head with new AMC cast heads and 42x36mm stainless steel valves, and stiffer springs?

Hydros bus lifters with the stock camshaft die at 4000 rpms due to the cam grind.
Solid bus lifters with the stock camshaft die at 4200 rpms due to the cam grind.
Both should have the valve lash checked at oil changes.
I have yet to see any change in valve clearance any of my HAM head equipped type 4 engines. The 914 has 20k on it and the Westy has about 15K on it and the other 914 5K but I still check.
The cam is what affects idle, cold start blah blah. The 9550 is nearly the same as the Web73 and both boost hp/torque but you get the crappy cold start idle plus cooler CHT's. You have to run the bigger valves for this cam and solid lifters.
Stock cam replacement should be the Web142 which is the stock 914 cam and with the bigger valves gives you hp to 4900 rpms plus some extra hp without the idle issues. This cam loves Ljet with its grind for a clean high vacuum at idle and you have to run solid lifters.

[luftvagon]

Fair enough. Good reason to keep everything in stock order. I've been in touch with Adrian from Headflow masters for the last 6 months. I'd like to give him my business since I've been pestering him as well. I just need to know the specific on his longblock, and will be giving him a call on Monday to put my order in.

I will have to solicit your help for the FI tuning, hopefully you guys don't mind.

In terms of clutch, I found this kit @ busdepot. http://busdepot.com/details.jsp?partnumber=028141999HD

Is there something else I should look at replacing? Broken Thermostat?

[luftvagon]

It was a very nice and warm day in Arkansas -- 60F, beautiful baby blue sky, and sunshine galore. I took this opportunity to address a few things; clean-up garbage previous owner left in every nook and cranny, and fix some switch issues which were messing up with my map light, and door ajar buzzer, and the rear tail light issue. Before the clean-up effort, I took the bus for a drive down to Arkansas river to enjoy my morning coffee while overlooking a lock & dam. On the way back, I stopped by car wash and pressure washed the under carriage.

When I got home the sun was at its highest point, and the work begun:





All this work makes you appreciate the Vagon even more. I am glad I will be supporting a competent builder, and I am looking forward to years of trouble free operation.

[Amskeptic]

Hydros bus lifters with the stock camshaft die at 4000 rpms due to the cam grind.
Solid bus lifters with the stock camshaft die at 4200 rpms due to the cam grind.

Is this the voice of personal experience, or what you have heard from the people you hired to upgrade your engines?
Honestly, if you have ever *driven* a 1700 Type 4 engine the damn thing pulls cleanly to 4,800 rpm, you know why? Because that is where the damn horsepower peak is. Look it up! If you drove a dog 1700 last year, it is because the poor thing was not in optimal condition.

I wish the upgrade engineers the best in the their endeavors, but that doesn't mean they are on the road with stock engineering. They gave up on it long ago. They have nothing but contempt for it. The stories get more dire by the year. They read graphs and show you how the torque curve peaks at 3,000 rpm and tell you it is done! at 4,000 rpm, but the actual output graph tells a different story because you have put the torque against the work being performed, and 4,000 rpm is doing more work than 3,000 rpm even if the torque has begun to fall off.

If VW states that the cruising speed for a 72-74 bus is 78 mph @ 4,600 rpm (look it up!) do you honestly think that they would set the cruising speed 400 rpm beyond "die"?
Would they set the cruising speed for all 2.0 engines at 2 mph past "die"?
Of course not. They set the cruising mph at maximum horsepower rpms.

Go find your Raby torque graph and see if he overlaid over the factory. Look at the maximum torque at 2,000 rpm. Let's say it is at 63 ft/lbs. Now look at the other side of the graph where the torque has dropped back down to 63 ft/lbs. Let's say that is at 4,400 rpm for a 2.0 (more like 5,100 rpm for a 1700). Now go hit the street in 3rd gear at 2,000 rpm (27 mph). Punch the gas. That is 63 ft/lbs right there, did you feel it? Yes the push will grow as you approach 3,000 rpm. So, hit the gas at 4,400 rpm (57 mph) in 3rd. You will get the same punch as at 27 mph, but now you will not feel the same sort of growth in power, but you are still *increasing work output*. With an early bus, you have good serious pull from 27 through 48 mph in 3rd, and it will pull up to 60 (as mentioned in the owner's manual) for brief periods, 5,400 rpm.

All of us could do well here to give cites for the information we have heard from others that we choose to share here *in answer to someone's specific questions*.

[Bleyseng]

I had a stock 72 bus for several years, so yes I have driven one for a extended period. The 1700 is not the same as the 2.0L which is what he is rebuilding. So I wasn't even thinking about the early 1700 engines.

in the 77 owners manual (I did look at the copy on theSamba) it states the 2.0L maximum SAE hp is 67 at 4200rpms while max torque is 101ftlbs at 3000rpms. Maximum and cruising speed is 75 mph which is confusing to me. Is it the max or is it the cruising speed as it seems odd that you can cruise but its the maximum speed.
The 914 spec's are in the 914 Presentation folder (see pic). The 2.0l bus cam and the 2.0l 914 cam were slightly different and SGKent has gone over this recently on thesamba a lot.
Raby's torque curves are dead flat and then fall off at 5000 rpms. They are on his site if you want to look them up or rather they used to be. I haven't looked at a stock bus 2.0L torque curve in a while so maybe you can post one.

[Amskeptic]

I had a stock 72 bus for several years, so yes I have driven one for a extended period. The 1700 is not the same as the 2.0L which is what he is rebuilding. So I wasn't even thinking about the early 1700 engines.

Maximum and cruising speed is 75 mph which is confusing to me.
Is it the max or is it the cruising speed as it seems odd that you can cruise but its the maximum speed.

Raby's torque curves are dead flat and then fall off at 5000 rpms.

You how dare you ... post a nice picture that I cannot read or maximize in my stupid browser?

VW played games with their advertising but it is easily decipherable.

They made a big point out of saying that the maximum speed was the same as the cruising speed to help get people declare a boundary that this is the car's limit. It would be more deleterious to an engine if you told people that their 1972 bus can do 97 mph and the 1977 bus can do 102 mph at redline, but please go 75, 'kay?
They arrived at their very specific top/cruising speed numbers where aerodynamic drag met horsepower met heat generation met expected fuel economy.

When ad copy says it will cruise all day at the car's maximum speed, we mechanically minded interpret as follows:
The engine can indefinitely sustain:

Type 1 1600 Beetle ... 3,950 rpm
Type 1 1600 snglprt Bus ... 3,950 rpm
Type1 1600 dualprt Bus ... 4,000 rpm
Type 4 17/1800 Bus ... 4,650 rpm
Type 4 2000 Bus ... 4,200 rpm

..... and THIS I live by.

If you look at shift points all in the owners manuals, they show you a very interesting proof of horsepower ... each maximum shift point is at the horsepower peak except for the Type 4 engines where they allow you 200 rpm below redline in 2nd and 3rd gear only (and briefly).
ColinButItISFun

[Bleyseng]

Sorry, but I am a long way from my usual resources of pics and dyno sheets in Seattle.

Yes, I use the 75 mph as the cruiseallday mark too as the engine seems to like it the best. Although Monique seems to think 80-85 mph is. I go by feel and sense the engine seems to be pushing it when at 80-85mph as gas mileage drops off but there is no difference in oil and CHT temps. Also, most cars can't cruise at their redline as its just the max rpms not the maximum cruising speed. My westy can rev to 5500 rpms without any problem but I certainly wouldn't cruise there.
The flip side is my 914 which can and has cruised at 115 mph (advertised max speed) for extended periods without any problem and still got 30 mpg.
So yes, aerodynamics does play a role in the max speed which the car can be driven for extended periods of time.