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cylinder heads
chop-chop - September 20th, 2010 at 08:32 PM

Gday, can you put larger barrels and cylinder heads onto smaller engines (ie 1600 barrels onto 1200 motor) to increase thier cc's without major mods.
cheers

vw54 - September 20th, 2010 at 08:39 PM

NO THERE AINT ENOUGH MEAT

IF U ARE GOING 1600 THEN U NEED 1300 OR 1500 MINIMUM

waveman1500 - September 20th, 2010 at 08:42 PM

The 1200cc cases are different and can't be converted to 1600cc. Any of the 1300cc, 1500cc or 1600cc cases are essentially the same and will accept 1600cc pistons, cylinders, heads and manifolds to upgrade it to 1600 twin port.

Craig Torrens - September 20th, 2010 at 08:54 PM

you can put a 1398cc big bore kit on a 1200cc motor :starhit:

1500S - September 20th, 2010 at 10:08 PM

Quote:
Originally posted by waveman1500
The 1200cc cases are different and can't be converted to 1600cc. Any of the 1300cc, 1500cc or 1600cc cases are essentially the same and will accept 1600cc pistons, cylinders, heads and manifolds to upgrade it to 1600 twin port.


1200 40hp cases can and have been converted to 1500/1600 cc . The crank fits in so all that needs to be done is the cylinder bores to accept the cyls for the bigger pots. They have even been used as a substitute case for the Type 3s during the 60s. The Bug dipstick tube was crimped and the hole drilled/studs fitted for the Type 3 filler/dipstick tube. Also the Bug oil pressure switch hole plugged for Type 3.

Would you believe that 1200 heads were even used on 1500 converted engines! Valves were a bit small :lol: but with twin carbs they had much more poke than the old 40 ponies! 1500 size heads became readily available when the industrial engines lost one side for the compressor head. We were paying around 50 bucks for a complete head in about 1968.

Back to the original question, if you convert from 1200 40hp then the case is about all you have left if you convert to 1500/1600 so not worth thinking about.


DH

waveman1500 - September 20th, 2010 at 11:55 PM

That's a pretty cool story 1500S. If you put enough effort into it you can do anything, but as I'm sure you realised I was trying to say which conversions were the easiest. Once you've gone to the effort of putting in a new crank and machining the cylinder holes out, instead of going up from 1200cc to 1600cc you could start with a 1600cc case and then put in a stroker crank and/or big bore pistons, taking you anywhere from 1835cc to well over 2 litres. This all requires expense though, and new parts and machining time. If you don't have an engine to begin with, then I would suggest that buying a complete 1600cc engine is easily better value for money than building one up. I've bought a good running 1600cc twin-port for $800 so you should easily find one under $1000.

So, if your car has a 1200cc engine, I would recommend deciding whether you care about keeping the 'vintage' style originality or not. If you don't mind, I would recommend a swap to a complete 1600cc twin-port, and keep your 1200 motor in the shed in case you ever want to restore it to original. If your car has a 1300cc motor or bigger which has a bottom-end in good condition, you can then decide whether you want to bother swapping pistons and heads or just swapping the whole engine. If you're interested in a real go-fast motor and you want to go over 1600cc, think about getting a second engine as a basis, and keeping your old 1300 or whatever as a spare. That way, you can drive the car with the 1300 in whilst you're building the hot motor, and then once the hot motor is in, if you ever want to sell the car, just put the original engine in and keep the hot one for yourself. This is necessary because a decent high-performance engine build will cost you thousands, but it does not necessarily add thousands of dollars to the value of the car.

1500S - September 21st, 2010 at 08:55 AM

What I was replying to was "The 1200cc cases are different and can't be converted to 1600cc" which isn't true as I have stated, a good story or not. I did say that from a 1200 conversion to 1500/1600 all you would have from the original was the case. The base casting of the 1200 and 1500 cases are near the same and many were converted during the 60s. On here we see quite a bit of misinformation regarding what can be done and what can't. We also see the output of twin port over single port where there are claims of much more power from the twin port with the standard single or standard dual carbs. The VW engineers couldn't get any increase so what hope do we have! Likewise with torque from FI over carbs................ all the same. The fact is that that the twin port heads were developed for the fuel injection setup which gave better polution control, not for power increase etc.

So, back on topic, can you put larger pots on a 1200 case without costly mods? Yes, with the same crankcase mod as a 1600 going to 1916, that is the holes bored to accept the 1600 pots except that the standard 1500/1600 heads can be used so the cost is much less.

DH

chop-chop - September 21st, 2010 at 09:14 AM

so what about putting twin port heads onto the 1200 single port. was thinking of doing something stupid, like turbo or blower just for shits and giggles. And just because i can!

1500S - September 21st, 2010 at 09:23 AM

Quote:
Originally posted by chop-chop
so what about putting twin port heads onto the 1200 single port. was thinking of doing something stupid, like turbo or blower just for shits and giggles. And just because i can!


No. The head recess on a 1500/1600 where the cylinder fits is too large in diameter for the 1200 cylinders to seal.

The last 1200 case I bored for 1600 was back in 1979 for a workmate at the old HMAS Nirimba Apprentice Training Establishment at Quakers Hill, NSW. I had enough 1500 bits taking up space to build a bottom end plus a pair of single port heads and twin Type 3 carb. Other than the linkages being a bit tedious, the engine performed as a daily driver for years.

Why did I do it? The same as you! Because I can. I walk into the workshop, clamp the case onto the mill, bore it and walk out with a 1600 case! :lol:

Just get a 1600 engine and put that in it.

bajachris88 - September 21st, 2010 at 11:22 AM

As a fond long term member of the association of laziness and slack, it is my duty to show some neat, cheap (in comparison with time and money) options that will give ur bug a little more go go juice.

I was trawling ebay and see the stuff u can score :tu:


dirt cheap 1300 running cc engine (then nab some 1600cc heads and pistons for a couple extra hundred, and there is no need for case machining! You could be done in an afternoon!)
http://cgi.ebay.com.au/vw-1300-motor-/160482909752?pt=LH_DefaultDomain_15&...

Carb kombi 2ltr
http://cgi.ebay.com.au/VW-1800-KOMBI-TYPE-4-MOTOR-ENGINE-/220671993664?pt=AU_...

EFI Kombi 2ltr
http://cgi.ebay.com.au/2L-VW-Kombi-Motor-/330474232444?pt=AU_Car_Parts_Access...


There are always dub engines popping up there... suprised there isn't any normal 1600cc ones... if u check each week there will eventually be one. :tu:

waveman1500 - September 21st, 2010 at 11:50 AM

Quote:
Originally posted by 1500S
What I was replying to was "The 1200cc cases are different and can't be converted to 1600cc" which isn't true as I have stated, a good story or not.


Sorry about that, all I meant is that it can't be done as a bolt-on swap.

1500S - September 21st, 2010 at 01:30 PM

Quote:
Originally posted by waveman1500
Quote:
Originally posted by 1500S
What I was replying to was "The 1200cc cases are different and can't be converted to 1600cc" which isn't true as I have stated, a good story or not.


Sorry about that, all I meant is that it can't be done as a bolt-on swap.


That's ok. We just have to be careful that we give the correct info here. Many of the mods were done long before some Dubbers knew Volkswagen existed!

I know that the cases of the 1200 can be upped to 1500/1600 as I machined quite a few in the 60s and 70s. The same case can be used on the Type 3s (early body to 68) with the oil filler mod. With running a Type 3 in the 60s I was always looking for a better engine and did just that with a 1965 1200 case which had the slipper cam bearings. That engine did 6 years of reliable daily running without any problems.

DH

Turbo54 - September 21st, 2010 at 01:56 PM

Quote:
Originally posted by chop-chop
so what about putting twin port heads onto the 1200 single port. was thinking of doing something stupid, like turbo or blower just for shits and giggles. And just because i can!


I was thinking to do the same on a 1200 motor, turbo that is but it will only be good for about 4-5 psi as the cranks have issues after that.
T54

chop-chop - September 21st, 2010 at 03:18 PM

though there might be crank issue's. interesting to find its limit with the blower though.8-10 psi? before heads get blown off.