Hi Guys
I want to rebuild my 2ltr kombi engine, I would like to have a bit more pulling power, but i have little knowladge of what way to go about it!
I know I have to have the heads done, bigger valves, big and little ends resized, rings ect ect, but, are carbs and a cam the way to go? or is a bigger cylinder displacement (more cube's) preferable!
I don't really want to stroke it, but if this is the best option I will do it!
If anyone can give me some detailed advise, on a set up and the parts that I will need, I can start sourcing them now, I will have have to buy the parts as I can afford them (one or two pieces at a time) so It will be a long term thing.
I don't want to be to radical, I just want to be able to pass trucks and caravans on the hy way, I only travel at 100-110 on the road, so I am not after a dragster! just a big improvement on the standard torque this engine put's out!
Thanks Rob....

Just a few general comments Rob, since I'm not into the type4 engines specifically.

Increasing capacity will help both torque and total power output, but stroking the engine has a greater effect on torque than boring it - for the same capacity. The reason is simple - increasing the stroke increases the leverage on the crankshaft and this tranlates directly into torque (the twisting force on the crankshaft).

Boring the engine does have some effect though, because it gives a harder push on the piston.

Going big-bore is simpler and cheaper - if your bottom end is in good condition and the case doesn't need to be opened.

Porting, better carbs and a mild cam can certainly make a big difference too - but remember that for TORQUE you want fairly conservative cam numbers - a big overlap cam will only come into it's own at high rpm.

One other solution would be supercharging - this requires almost no changes to the engine itself, and so it relatively easy to install. There are a few Toyota superchargers around which might do the job.

I've seen one interesting set up (on a 1776 bug) with an airconditioning type electro clutch on the Toyota supercharger pulley, so the supercharger could be turned on when needed, and just freewheeled when it wasn't needed - giving a good combination of economy and POWER when it was needed. This guy (with an otherwise unremarkable 1776 in a 1970 "shit box" bug), could accelerate past V8s going up the Expressway through the Adelaide Hills.

I agree with Rob. :thumb

I think in terms of torque for your dollar, the best option is possibly the supercharger. If you want to keep it stock though, find a nice factory fuel-injected 2L. I know a lot of people don't like (understand) them, but mine used to fly up hills. It's a great feeling to overtake Falcadores going up hills in a kombi!!!

Hi Rob thanks for the reply!
What size barrels and piston kit would you recomend, from memory 2ltr's have 94mil barrels, what is the maximum size before you have to cut the heads & block to suit, and who is the best manufacturer of these kits, and who stocks them!
I have changed the oil every 5 thou, and the filter every ten, so my bottom end should be OK, resizing and new bearings, should be all I need to do.
All I need is more grunt for the hills and overtaking, bottom end power is what I am after! once I get her to 100 thats fast enough.
Rob.....

I'd love to hear more about the supercharger option (especially the one that can be turned on or off). I don't really know anything about superchargers at the moment, so any info/explanations will be greatly appreciated.

go for 96mm pistons and cylinders, they dont require any cutting.

Remember the stock 2.0L euro spec 914 engine put out 100hp, so with a bit of tuning and a good exhaust u could do better.

Does anyone know the difference in power and torque (for stock motor) between dual carb and FI?? I don't think it was much.
As for the 914 motor, they had much bigger valves (bigger than 1.8L heads) and a different cam, so was the torque any better than a kombi 2L, or did it just rev harder for the extra power?
It would be interesting to compare the specs on a late FI wasserboxer as they had MUCH more torque but only a minor HP increase, just what the Kombi needed.

Supercharging would be in a pull-through-the-carb setup wouldnt it? I think that's the simplest design and probably the cheapest.
My friend has a mini with a toyota supercharger sucking through his standard carb with standard internals and he gets 80 or so hp from the standard 60. It's quite quick.
I imagine a 1916 would pull the kombi frickin hard.
:thumb

Andy, I couldn't tell you in definite figures, but I have heard figures of between 3 to 7 hp, probably closer to 3 I think. Remember though that this is PEAK horsepower. The fuel injected variety produces much nicer power at other points in the rev range, particularly down low, without the stuttering and hesitation inherent with carburettored engines. They also start beautifully when cold. :thumb The only problem I had with my FI 2L was keeping my foot off the juice; it was just too much fun surprising the crap out of people, overtaking them uphill at 120 or so!! :thumb:thumb

I am looking at s/charging my T4 2ltr with an
electomagnetic clutch from a Toyota 2ltr,operated by microswitch on the throttle linkage. This is to get the boost to come on in just the right place, around 3000 rpm. EFI engines have this controled by the computer.No such luck unless you fit a Wolf3D engine management system.$$$$
With my set up, i will be going to a single carb of which i am still to work out and also fitting 96mm pistons. Dont think i will change the stock cam as the engine is tuned for torque not peak HP as this is a already a commercial engine.

I thoght of getting a crank with a longer stroke (78mm - 84mm) but the cost is not worth it. Just make sure your bootm end is in good condition and the comp ratio no higher than 8:1. Longer rods also help with more torque due to piston speed.

Power to ya!!! Todd

Dont forget the clutch!!!
Not much good having more power if you cant get it to the wheels. May have to beef it up if you go to far. Good thing the 2ltr has a bigger surface area.

A quick search shows 2L FI and dual carb at the same HP (70@4200rpm).
Only found torque figures for 1.8, FI and dual carb both had the same max torque, but the FI gets it 600rpm?? sooner @2400rpm
Interesting 1.8 to 2L, only 2 hp and ~8ftlb difference!
Late FI wasserboxer (2.1L) jumped to 90hp@5500rpm and 120ftlb@3200rpm

My brothers '90 vanagon will happily hold 110km with over 1 tonne on the back over a hill my 2L will struggle over empty!!

Just thinking out aloud hear (dangerous I know!!)
I wonder how much difference just putting 1.8L heads on a stock 2L motor would make??

Used to be a popular convesion - the 1.8s actually had larger ports and valves from memory, but this would actually tend to decrease torque with the same displacement.

A larger displacement with stock heads will give the greatest increase in torque (within conservative limits - type 4s can be bloody expensive to seriously warm.) Of course, an increase in stroke will magnify this, but strokers are on the costly side, especially with a type 4.

tell me more on this supercharging idea i like it!!!! who's the guy that has done it on this forum???
whats the supercharger they use?
cheers
rhys

Porsche 914s did use the same basic engine as the Type 4 sedans (411 and 412), and the ones in Kombis. There were a number of 914 engine specifications.

1.7 litre - W and EA engine numbers. 90mm x 66mm bore and stroke, 1679cc. 8.2:1 compression. 80 hp @ 4900 rpm. There was also a low compression - 7.3:1 version with EB engine number that produced 72 hp @ 5000 rpm.

1.8 litre - EC engine number. 93mm x 66mm bore and stroke, 1795cc. 7.3:1 compression. 79 hp @ 4800 rpm.

2.0 litre - GA engine number. 94mm x 71mm bore and stroke, 1971cc. 7.6:1 compression. 95 hp @ 4900 rpm. Also the later GC engine number - same size and compression but 88 hp @ 4900 rpm.

Kombi engines had 7:3:1 compression and produced 71hp @ 4200 rpm in 2.0-litre form.

The largest cylinders that 'slip in' are 96mm. These have the same outside diameter as the 93mm cylinders used on the 1.8-litre engine, so you can imagine how thinner the cylinder walls are. The largest oversize pistons VW made were 95mm. A 96x71 engine is 2056cc, but I don't know how long it would last - the thin cylinder walls would be subject to warpage after a few tens of thousands of km.

103mm cylinders have the same wall thickness as stock 94mm cylinders, but require heads and case to be machined to fit. With a stock crank it will give you 2366cc.

Over at http://www.shoptalkforums.com  they have a "forced induction" forum - certainly worth a look.

Two books mentioned frequently are "Supercharged" and "Maximum Boost" by Corky Bell - might be worth looking for (Amazon.com perhaps)

Steve, from Flat Four VW club.
one link on this forum is
http://www.aussieveedubbers.com/forum/viewthread.php?tid=442 
-
he's experimenting with water injection at present.

the link to water injection for Steve
http://www.aussieveedubbers.com/forum/viewthread.php?tid=3737 

and some more pics to see the blower
http://www.aussieveedubbers.com/forum/viewthread.php?tid=439 

His is only a 1640cc type 1 engine but you get the idea of the improvement.
CBBVW.com is Toyota blowing a Type 4 at present.
I think if I was setting up a car with the electric clutch driven blower, I would make it switch operated so that it could be used at any necessary time.
Even if hauling up a hill with load at 2400 rpm.
Or ready at idle to shoot ahead of the cars at the traffic lights before the parked car ahead.
Blowers give grunt at all engine revs not just at 3000 rpm and above.
There is definately an advantage in fuel economy to have it switched off when not needed.