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When I browse these forums I find something about the crossflow SOHC head made by the Opel Sport division around 1970. These heads were as correctly described here developed for racing - in particular for road rally - where the Opel's were very popular in the 60'ties and 70'ties. The crossflow single-cam aluminum head was however not really living up to expectations allthough Opel won many rallies with the Ascona A in 73-74. And later world champion Walther Röhrl won the European drivers championship (no world championship existed in those years) in 1974.

Swedish tuners around famous Swedish rally driver Lillebror Nassenius found they could make a new cast of the original cast iron head and make it perform similar to the works-head. And so they did. This Swedish head was so popular (and cheap) that soon the works division at Opel simply copied it. And used for works supported rally teams all over.

This means the head was also homologated, and this consequently means that this head is the only practical way to make a competitive historic race/rally car from an Ascona/Manta A or the GT or the Kadett B.

They still exist, and sometimes they appear at the German E-bay. At prices around 2-3.000 euros.

A properly prepared 2.000 ccm rally-engine with head produces just below 200 hp.

And this is the reason why the crossflow head is never seen anywhere or considered remanufactured.

So the question is: Can anybody confirm this, did any of these heads ever make it to the States?
 

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So the question is: Can anybody confirm this, did any of these heads ever make it to the states?
I have two (new) Sweden heads myself. I know of at least one more that came to the US in 1984, from Irmscher UK.

I also imported an XR2EH head (Kadett GT/E 2.0) head some years ago from Sweden, also new in the box.
 

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Opelnut
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rusty heads

:confused: just curious. Are those heads in photo still usable if cleaned up? I have tossed heads that looked like that thinking that they were to "rusty" to use.




would love a crossflow head in any condition for the collection:yup:


I have two (new) Sweden heads myself. I know of at least one more that came to the US in 1984, from Irmscher UK.

I also imported an XR2EH head (Kadett GT/E 2.0) head some years ago, also new.
 

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:confused: just curious. Are those heads in photo still usable if cleaned up? I have tossed heads that looked like that thinking that they were to "rusty" to use.
Just surface rust, since they were stored in my barn for 10 years and I live on the river...lots of humidity.

My machinist has a shotblast cabinet that shoots steel shot (similar to shotpeening) and will make it look like new. Just gotta remove the soft parts or at least mask everything off first (cam bearings, etc). I recently had a block done this way and it even gets the coolant passages nice and shiny.

Plus the steel shot is larger than glass bead or sand so it doesn't get caught in the nooks and crannies, only to come out later on and destroy your new engine!
 

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swedish heads

I have two (new) Sweden heads myself. I know of at least one more that came to the US in 1984, from Irmscher UK.

I also imported an XR2EH head (Kadett GT/E 2.0) head some years ago, also new.
These heads were indeed produced by Opel and the flow numbers were head & sholders above the stock 1.9 & 2.0 heads. Opel produced I believe about 56 of these heads. When Tony Fall was still at Opel, I personally seen 7 on the shelf in the warehouse. The biggest problem for a carburated engine was that the ports were raised and with a longer opening than the 1.9 & 2.0 head and had a much better shot for the fuel charge to the valve, but you had to do a lot of work to fit an intake manifold to the head and make it look somewhat stock. We made a two 2brl. holley manifold out of a aluminum sailboat mast with a top plate that had the holley flanges bolted on top of the sailboat mast that was cut in half(like a log manifold). Trick looking setup but we never got around to running it on and engine so I don't know how well it would have ran.
 

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What's stamped on the two heads?
X20 or X20-G2 ??

Supposedly, the X20 are the original Swedish built and the X20-G2 are the copies from Rüsselsheim. But I'm not sure.

What's the difference between those and the Kadett GT/E head?
The works Kadett GT/E's were equipped with a 16-valve head, which never worked satisfactory. They almost ruined the career of later world champion Walther Röhrl.
 

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What's stamped on the two heads?
X20 or X20-G2 ??

Supposedly, the X20 are the original swedish built and the X20-G2 are the copies from Rüsselsheim. But i'm not sure.
Mine are both X2OG2 stamped.

What's the difference between those and the Kadett GT/E head?
The works Kadett GT/E's were equipped with a 16-valve head, which never worked satisfactory. They almost ruined the career of later world champion Walther Röhrl.
The XR2EH head was used in production form on the Kadett GT/E. Looks like a normal 2.0E head, but has slightly improved inlet and exhaust ports, and a smaller combustion chamber (looks like 1.9 chamber, not like 2.0 chamber). It is also skimmed 1.0 mm as delivered from Opel. I have heard that the casting is also thicker for more porting ability.
 

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How many cast-ribs can be seen forward next to the cam-cover? Towards the sparkplugs. Two or four?

Suddenly remembered: The GT/E was produced in a 1.000 pcs series - homologated for motorsport with the big limited slip diff and ZF 5-speed gearbox (even with the straight 5th on request) and many small improvements. And they had a 1,9 ltr fuel-injected engine with 115 hp. And those engines were marked 19EH and the heads X20EH.
They were improved standard heads unlike the Sweden heads which were only for top performance engines.
I think your head may be a later version but not sure.
 

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How many cast-ribs can be seen forward next to the cam-cover? Towards the sparkplugs. Two or four?
On my XR2EH head, there are two (2) ribs.

On my X20G2 Swedenhead, there are zero (0) ribs.
 

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More info:

My X2oG2 head, cast in 1980, part # 314748
 

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My XR2EH head, cast in 1989, part # 90090489
 

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Discussion Starter #12
I think that's incredible exciting. With two ribs it's the original head for the EH-engine.

The 1.000 series Kadett GT/E have almost mythological status in Europe among Opel-fans, so the proper spareparts for them are rare and sought after, if to be kept historical correct.

I don't remember if the 1.000 series were homologated for group 1 (the standard class), but i remember the GT/E was very popular in this class. The restrictions were unbelievable hard. No conversions of any kind allowed, not even the airfilter or the seats. And the rallies in the Europe at that time were very tough, so it was often a question of surviving rather than topspeed. And here the rugged construction of the Kadett made a huge diffence.
 

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Discussion Starter #13
About the X20G2 head (the sweden head). It's amazing to think that they were originally constructed in the early seventies and then the Opel works also homologated them for the Ascona B.
And the Ascona B was made as a special consignment by Irmscher as the Ascona i2000. The litlle i not standing for "injection" but for "Irmscher". Sold and distributed by the Opel dealers as sports-version but really mostly intended for the homologation in a standard class which demanded 5.000 pcs sold in one year.
Allthough in the shadow of the very popular Ascona 400 the i2000 was homologated as group A (the new FIA standard class) where the rules were also strict but allowing for some modifications. The pistons, rods and cams were free and the swedish tuner ENEM managed to build these standard engines to a performance of just around 200 hp. And the Ascona was almost without competion in it's class. Think it was in 1984 the swedish driver Matts Jönsson finished overall 6th in his old privately entered Ascona i2000 group A in the british rally worldchampionship event (the RAC-rally) competing against fourwheeldriven 500 hp Audi quattro's and the like.
 

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These are also probably not too common!

The last photo shows a ported Irmscher short intake (for normal 1.9 or 2.0 head) compared to an as-cast 'Swedenhead' intake.
 

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Discussion Starter #16
Yep, that's true. The swedish head could only be used together with these special intake-manifolds for twin webers or multiport fuelinjection. Nothing else would fit them.

In the late 80'ties and early 90'ties you could actually just order the head and the manifolds from your Opel-dealer as original spareparts no. 40 06 225.

But nowadays they are very rare, and also a bit outdated, as the 2,2 ltr head is of similar construction but with a better flow for civil use. I think a properly ported 2,2 head can perform very close to these old swedenheads, but they are not legal for historic racing.
 

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Suddenly remembered: The GT/E was produced in a 1.000 pcs series - homologated for motorsport with the big limited slip diff and ZF 5-speed gearbox (even with the straight 5th on request) and many small improvements. And they had a 1,9 ltr fuel-injected engine with 115 hp. And those engines were marked 19EH and the heads X20EH.
The Kadett 1000series had a 2.0EH engine with 115hp at 5,600rpm, not an 1.9. The compression was raised from 9.4 to 9.6. Max torque 159Nm at 3,000rpm.

Dieter
 

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But nowadays they are very rare, and also a bit outdated, as the 2,2 ltr head is of similar construction but with a better flow for civil use. I think a properly ported 2,2 head can perform very close to these old swedenheads, but they are not legal for historic racing.
Very true, the 2.2 and 2.4 heads are a better design than the Swedenheads and provide a more useable power delivery.

Not to mention, as time (and technology) has progressed, there are plenty of tuners that have surpassed 210-230 hp with normal 1.9 or 2.0 heads, making more power than even the original alloy crossflows made!
 

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The Kadett 1000series had a 2.0EH engine with 115hp at 5,600rpm, not an 1.9. The compression was raised from 9.4 to 9.6. Max torque 159Nm at 3,000rpm.

Dieter
You're absolutely right. My memory was playing tricks with me.
The first series GT/E (1975-1977) had a 1,9 ltr 105 hp fuelinjected engine. The second series (1977-1979) was the 1000series and it had a 2,0 ltr 115 hp engine.
 
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