I have a 2.0L type IV with square port bus heads on it. I can simply swap for a set of 1.8 or 2.0 porsche heads and bolt my exhaust right on. I'm wondering if I should use the square port heads and modify the exhaust. I have 4 good stubs that I wouldnt mind using from the old exhaust system. These are amc heads with either 39.3x34 or 41x34 valves. I'm thinking I'm going to build a 2056 due to needing the cylinders bored anyway. I have been told the exhaust port flows much better on the square port heads. I have no problem welding up the exhaust. What do you guys think I should do?

John

I think the square port heads mostly seal better. If they do flow better, why is that so? Is it just because the ports are already enlarged compared to 914 2.0 heads?

Exhaust port measures ~1.400"x~.950" I did notice it looks like CFR makes makes level 4 stub pipes for a sq port.

John

What are amc heads?

They are a spanish cast replacement head for the VW bus engines. They are around $300ea new. I'm still trying to nail down the valve sizes. From aircooled.net is looks like these only come in 41x34 unless you step up to 45x38 which I definately dont have.

This is what Aircooled.net has to say about them. These guys seem to be pretty honest but then again they are trying to sell parts.
"These are NEW HEADS built from AMC castings, and are much stronger castings and better quality then the stock heads you had when the engine was new. The AMC Castings (excellent) are optimized by putting NEW SEATS AND GUIDES in them, at the proper press fit for no more "headaches". These utilize the 1.8 / 2.0L bore size (94/96mm), and are sold PER EACH. Complete heads have 7mm stem valves for light weight and better flow thru the ports.! ALL heads have the threaded FI temp sensor boss for FI systems. Be aware that these heads use the 79 1/2' and newer exhaust port and exhaust system, the one with a real gasket! We have adapter flanges you can weld onto your 79' and earlier style exhaust system. We recommend the vanagon port, it flows much better, and is less prone to exhaust leaks at the head!"

John

The casting is good but toss the seats, valves, guides, springs, retainers and keepers. Only the casting is good.

Buy new SS valves and seats from Manley or SSI if carbed (or PEFI) I would use 44mmX38mm,if stock FI use 42mmX36MM. Open up the ports to fit the new seats.

Use new springs (Web, crane, stock,etc), retainers and keepers (Berg or bugpack) and guides (OEM).

P.S. this also is how Raby does all his new heads.

Jake Raby uses square-port Bus heads? I think he gets most of his heads from HeadFlowMasters. I phoned HFM and asked them about the 42 x 36 mm heads they have advertised and they said they were rebuilt 1.8 heads.

I had S/S valves from that jerkoff Mark Stephens....they leak. Stay with the sodium ones....

Raby will use both, I believe, not long ago he stated that he will only use new and 2.0 914 heads on his engines.

Stephens was a dick, he used the cheapest El-stinko SS valves, there is some real crap out there.
Only use the Manely or SSI brand SS valves and steel (cr-mo) seats never cast.

Sodium's have been known to break, I have a couple of engines in my scrap pile because of them.

I have done a couple of heads in my day, so I just may know what I'm talking about.

Looks like you've had plenty of head.....

Homer Simpson Voice: Mmmm - cylinder heads

Thanks for the comments guys but you still didnt quite answer my questions. Should I modify the exhaust for the square port heads? Do they flow better and if so, why? Does anyone have square port heads in their 914?

John

Jake Raby could probably answer that http://www.germanlook.com/Forums/forumdisp....php?forumid=29 .

Out of the box...no.

With some large dollar flowbench work...maybe.

Most would do it for better exhaust gasket...although I don't have much problem with the oval port and a good exhaust.


"Does anyone have square port heads in their 914?"

No, I have 1800S heads with 42mmX38mm valves and on my new (future) 2270 I'll be using 2.0 914 heads with 44mmX38mm valves .

Ok, so now I gotta print this whole thread out again.

Outta the box the 914 2.0L heads are the best, period.
With work ($$$$) the AMC can be nice, but with the same ($$$$) put into the 2.0L heads you will make more power.

Geoff