ah, now that my kombi is actually on the road I have SO many questions!

In John Muir's guide to VWs for complete idiots it says that you shouldn't overlug the engine, but one of my friends who did a lot of work on the car to get it roadworthy says that I should get it into 4th quickly (so taht I don't wear my clutch quickly), so what should i do?

In John Muirs book it gives a guide of when to change gears, but its all in miles/hr not km/hr, does anybody know it in km/hr? or can give me any tips in this area.

thanks

dodge

yeah 80km is roughly 50 miles

a clutch only wears when you are using it! nothng to do with getting it into top quickly.. kms to miles multiply by.62

60kmh is 37mph 80kmh is 50mph 100kmh is 62mph
60kmh in 4th is not really good for a standard kombi except on the flat or very slight slopes

[Edited on 14-7-2004 by kombikim]

You can go up a big hill or mountain flat out in 3rd gear...
it has nothing to do with Your Clutch...
only when You change gears....

Was He really a mechanic...????
Top gear is an Overdrive in VWs... for cruising on the highways only... You would be lugging the engine using 4th around town... unless You were driving fast on flat ground...
VW engines like to rev [so do most modern engines today] not labour them... which kills them...

Lee

I too read that section in John Muirs book, I too was nervous about lugging my engine so I gave alot of attention to how I was driving my bus.

What I found was that very quickly I became more concerned about the engine then actually driving safely on the road

It is good that you want to be aware of what you are doing to your motor and my advise is get in it and go for a squirt around, get used to what the gears can and can't do, get up it a little to find out what your motor is capable of, lug it very breifly to find out what that feels like and in no time at all you will be aware of how your motor sounds when it is lugging and when you are just a little too high in the rpm. You will need to do this in order to find the 'middle' ground for the motor. Then in no time at all you can select the appropriate gear just by listening to how it sounds.

Here is a guide to converting MPH for the road. These figures are not exact but these figures won't get you booked for speeding and won't get your brain fried trying to remember them.

20mph = 32kph
30mph = 50kph
40mph = 65kph
50mph = 80kph
60mph = 95kph
100mph = 160kph - not that we bus drivers need this one, but hey we can dream

If you want to do conversions easily without thinking about it try Google. Enter "<number>kph in mph" or vice versa and it'll tell you the answer.

[Edited on 14-7-2004 by andrewh]

Dodge just drive it & you'll feel it.As you get to know your kombi you'll feel when the gears need to be changed.I've had the kombi that i've got at the moment for about 6 years & i've never had to get another clutch....afew clutch cables but thats no big deal.
The more you drive her you'll know what feels right or when something doesn't feel quite right & remember every car has its own little quirks that is only theirs so don't worry just take her for a cruise & get to know her!!!!

If you get some little stickers you can stick them on each point of your speedo for reference..e.g 60kms,80kms etc.....so it makes it easier to tell which speed your doing without having to remember the conversion everytime.

Now I can see why you think "VW engines like to rev" :duh


And Lee, if your going to quote me, don't edit the quote and take it out of context. :cussing

less revs + more load = more heat. when your engine's revving slowly and given a lot of throttle (ie lugging), the heat builds up quickly, and your engine will not be happy. Like its been said, just change when it feels right. If you're really worried about your clutch, don't use it! Haha..umm, yeah. I drove my S beetle from Bathurst to near Chinchilla with no ability to declutch. and I've driven the kombi a decent stretch with a snapped clutch cable. A good skill to have, but best not used unless needed.

thanks for your advice guys!

Yeah that was interesting reading in the Muir book, but I'm concerned about what KruizinK' said: "a rule for stock buses though, I think changing in to top at around 70-80 kmh is a good bet". I don't go over 60 in 3rd. I have an 1800, not a 1600 or earlier one, I'm not sure what kind Kruizin has in mind, in case it matters.

See, at 60 in 3rd, the engine's doing 3000rpm. It should be able to go faster right, but I once went to 80 in third, and the poor thing sounded like it was going to blow up, and the brake and battery warning lights started flickering at 3200 rpm. Hence, I don't rev it above 3000.

On the other hand, I almost never floor the pedal either, certainly not at less than, say 2000rpm. I know what pinging is, and she doesn't do that.

It just feels wrong at >3000! Am *I* wrong?
Regards, Aurel.

I'll try not to misquote dude!

yeah well i've spent these last few days just listening to my engine and i tend to agree with you there aggri. I'm changing to fourth on about 60 otherwise the revs just get too high for my liking. I have an 1800 too....

Well, listening to the engine is your best bet, so you are both probably doing what suits your buses. My estimates are based on my current 1800 which was completely reco'd and balanced 12 months ago. It was noticably noisier before the rebuild, especially at revs. Now it sings at revs, and it will happily rev to 5500 in first, and I usually won't go past 5000 in 2nd and 3rd. It will quite happily pull just under 4500 rpm for extended periods at 100 kmh in third (Bigger-than-stock tyres). It has been to 6500rpm once, accidentally, with no apparent damage. Honestly though, with a stock carbs and tyres, etc. I don't believe there is any real benefit in revving past 4500rpm. I have a factory type 3 tacho installed which redlines at 4500rpm and I am happy to use this as a guide for the kombi engine. Even with my big tyres, I often change up at 3500-4500rpm if pottering around town taking it easy.

Bottom line is, listen to your motor. If it is getting a bit tired, then obviously you won't feel comfortable revving it to the same revs as a new motor.

General Failure, I see what you are saying by "less revs + more load = more heat.", but less revs means fewer combustions in a given time. I know there are a lot of other factors, but I don't think that cruising along at (for example) 3000 rpm in top is going to be any more detrimental for the engine than changing down and pulling 4300rpm in third. Granted, the fan spins faster at 4300rpm, increasing the engines ability to disperse heat, but with fewer combustion cycles at 3000rpm, something would have to balance out somewhere.

Another angle to consider is that regardless of the gear/revs used, the work done is the same at a given road speed/acceleration, so therefore the heat generated should be the same, in which case it is probably better to change down and increase the fan speed. I don't know. I guess this is where we need the expertise of someone like Wes to share his experience, because I don't have the answers.

my problem is I don't have a revometer (or whateva their called) in my car so I don't even know how many revs I'm doin when I change. I just listen to the engine to guess. I guess getting a revometer would be a good idea.

Kruizin my engine is already fairly noisy. The pistons are noisy, or something. My engine was rebuilt just before I got it, about 18 months ago, so I don't really have the heart (or the money) to do it again too soon...

I agree with what you said Kruizin Kol. Under normal circumstances it does balance out. Pretty much, anyway. But if you plant it at low revs in a high gear, there is an excess of air/fuel going into the motor which it can't use effectively. There's a lot more burn for the cooling system to cope with.
This next bit is just a guess based on hazy memories from physics.
I remember that when a gas is compressed, the atoms are condensed and can't vibrate as freely, which means they have excess energy. So atoms, being the smart little cookies they are, try to ditch their excess energy into the surrounding environment, making it hotter. Basically how a fridge works. Anyway, here's what I'm getting at. You have more mix going into a cylinder. More burns because there is enough oxygen for combustion of all the fuel. Because it all burns, or at least the majority of it, the pressure in the cylinder goes up. Because there is excess pressure, more heat is dissipated into the chambers, heating the engine. Like I said, just a guess, but it sorta works, I think.

On a lighter note, it all reminds me of my S beetle. Always spitting unburned fuel out the exhaust. That car has issues.

Oh yeah. Something else I thought of. A certain RPM equates to a certain Speed in a certain gear. So if you feel like it, and if you know all the ratios for your box and diff you can calculate the revs your engine is doing. While it's in gear of course.
I'm only saying this because I'm reminded of an old truck I once saw. The manufacturers decided to economise on instrumentation, and only gave it a tacho. It had the RPM and the speeds for each gear listed on the gauge. I guess it'd work really well if it was calibrated properly.
Or you could just get a tachometer. I've got a 4 digit digital jobbie from dicky smith in my bay. Mounted it in the blank gauge hole. Calibrated it with a C64 power supply. Works perfectly.
Oddly enough, it didn't work on my S beetle. It just gave random readings.