Saab Head Replacement

[king1008]

Hi guys,

I am having serious problems with the cylinder head on my Astra G (z22se engine) and I am currently thinking of replacing it with the saab cylinder head (b207). I have a couple of questions about the modifications needed to the head in order to fit in the car.

Can I use the valves and camshafts that are already on the saab head without replacing them with z22se ones?

Should I replace the standard ECU?

Are there any necessary modifications on the z22se exhaust manifold or I need a new one?

 

[vocky]

the saab cams are not the same, so you would lose power. It is not quite a straight swap and you need to modify the exhaust cam auxillary take off, there are a few threads on here showing you what to do

 

[king1008]

Thanks for your answer
My main concerns are keeping the saab valves (mine are gone) and the current ECU, otherwise I am familiar with the other modifications.

 

[vocky]

the saab valves are much better than the z22se, so no need to change them, the valve springs are exactly the same.

Just the saab cams are very mild and you would lose some bhp, but if you need to use them they will run okay.

 

[Tubbe]

I have one stupid question. Can I use the z20net spark plugs with z22se running NA with z20net head? At least I know the gap is different. z22se plugs 1.1 and z20net 0.8mm. Will my engine run smoothly with the turbo plugs?

 

[evocarlos]

you could just get a new set of gm plugs for like £12 or platinums for £22
read mine to be anywhere from 1.0 - 0.8
the coil pack takes care of the rest

 

[vocky]

you cannot and must not use z22se spark plugs in a saab b207 / z20net head, they are too long and have a different method of sealing, theb207 / z20net have flat washer seals rather than the z22se taper seal.

I use audi 1.8 T plugs in my engine.

 

[Tubbe]

One question came to my mind during porting. At the moment I'm porting my saab head and the first exhaust port is nearly ready just needs polishing. Is there certain places where you should not take away too much material? I mean that you can ruin your head by removing too much material and then the exhaust port starts to leak to the water galleries. I'm using a washer that is nearly as big as the exhaust valve exit so I know when there is enough material removed. Also the exhaust ports are matched to the z22se exhaust gasket so not that big as the alfa ones

 

[vocky]

that's how I did my saab head, so you should be fine. The alfa gasket is too big to use for a porting guide - you would open the ports to the water gallery if you matched that gasket. But if you leave 1.5mm all round it should be okay.