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NEED A PAIR OF 412 2 LTR. PORSCHE HEADS. WOULD PREFER SOMETHING THAT'S BOLT UP READY, BUT A REBUILDABLE PAIR WILL WORK. GOT ANY TAKERS?

You are mixing your types a little. There was never a 2.0 offered in the 412. Only the 1.7 and 1.8. The 2.0 was bus and 914 only. The 914 2.0 was unique...different than the bus. Take a look at Tunas web site. It explains all. Ray

Ray, you ever run a 914 2 litre in a Type 4?

you want stock 914 2.0L or modified?

sraey8 wrote:NEED A PAIR OF 412 2 LTR. PORSCHE HEADS. WOULD PREFER SOMETHING THAT'S BOLT UP READY, BUT A REBUILDABLE PAIR WILL WORK. GOT ANY TAKERS?

No. I have not. I am not really that interested in the 2.0 914 engine. The heads, though better flowing....are too expensive for what benefits they offer. With correct porting, good exhaust and ignition, better cam and valves.....and a lot of injection tuning... I can make as much HP as a stock 2.0 914...with a 1.7. It will be more dependable and will be cheaper in parts. The 1.7 head is also not prone to cracks around the spark plug either. Ray

My bad, it was 914, Not 912. Don't know what i was thinking.

raygreenwood wrote:No. I have not. I am not really that interested in the 2.0 914 engine. The heads, though better flowing....are too expensive for what benefits they offer. With correct porting, good exhaust and ignition, better cam and valves.....and a lot of injection tuning... I can make as much HP as a stock 2.0 914...with a 1.7. It will be more dependable and will be cheaper in parts. The 1.7 head is also not prone to cracks around the spark plug either. Ray

I agree the 914 heads are WAY WACKY in their price, thats why I go with the Bus AW heads as I mentioned in another thread.

How do the 1.8 liter heads compare to the 1.7 & 2.0 in terms of flow and dependability?

Well If you have the Valve seats replaced with the newer kind which dont fall out. You port and polish them, get a good valve job done on them, they flow VERY WELL. When VW went fuel injection the valve sizes in late 1.8 heads and 2.0 heads became very small. I am just talking of Valve size, AW engine code heads are the largest valve BUS heads with the 1.7's being the next biggest, 1.8 and 2.0 being the smallest.

those aw engine code heads; how do i varify if a head came from that engine? and how does it's valve sizes compare to that of a genuine porshe 2.0 ltr. head?

Anonymous wrote:those aw engine code heads; how do i varify if a head came from that engine? and how does it's valve sizes compare to that of a genuine porshe 2.0 ltr. head?

You would have to compare part numbers, the different style heads have different part numbers. the AW 1.8 valves are somewhat smaller than the 2 litre porsche heads. But remember just slapping used AW heads on a 2 litre engine wont neseserally give you performance.

the reason i ask is because i have a opportunity to pick up a pair of 1.8's for cheeeeeeeeap, and that would leave me with plenty of room to port, polish, and re-valve before reaching what I would have spent on a pair of 914 2.0's. So i could maybe end up with a more dependable head that will outflow a 2.0 head with less $ invested. Historically, will the 1.8 head be as tough and hold up as well as the 1.7 head that I keep hearing is so durable?

I have never heard of to many problems with 1.8 heads. As long as the Valve seats are replaced.

The 1.8 heads hold up quite well. But... The actual combustion chamber shape with its quench areas in the 1.7 are one of the best combustion chamber shapes in my opinion. But...bear in mind, the shape as stock is designed to work with the dome pistons. The only other problem with the 1.7...is the small chamber. When you flycut for larger jugs, the quench areas will increase....and given the small chamber volume...will drive your compression way high, necessitating a really poor combination of barrel shims...and making an inefficent combustion chamber. That being said....the 1.7 flycut for 1.8 and 2.0 cylinders will now have a cylinder seating surface farther out than it did. It gives you more meat for a skilled porting person to use. In a basically just unshrouded 1.7...42 x 36 is the largest valve size with new seats you can put in, before the intake valve undercuts the seating ring of the cylinder. After flycutting the 1.7...you can go to larger seats and valves. You will also have enlarged the deck like quench areas,.....so a skilled person, could reshape the combustion chamber to allow nearly the exact same stock shape of the 1.7...with its dimple to operate with the domes, not lose any of the stock quench areas...and have better flow as well. The 1.8's are good...but the 1.7's are better for those having work done in my opinion. Ray

what do i look for in a head to distinguish the difference between 1.7, 1.8, and 2.0? How do i look at a head and know what it came off of when the seller doesn't know?