Rich9928p

Has anyone developed a good solution, such as machining off the water passage and capping it, so 8-valve 944 heads would fit on 16-valve 928 motors? The advantage would be the same as the hard to find Euro S heads, they use the same "larger" valves as compared to non-S and US spec 16 valve 928s.

Since 944 heads are plentiful and relatively less expensive, this could be a good way to go for those looking for more HP out of the old 16-valve 928 motor. This would make two less items to find from the EURO parts bin, you'd still want the larger runners and throttle body.

Rich

Wolfmaniser

I haven't done the measurements, but I don't think
two rights make a left, the cam gear would point at
the driver. You might port/polish the 928 heads, and
use 944 valves, if they're larger. Again, I don't know
944 specs. But modding a 944 head to fit might equal
modding a 928 head to flow as well.

Jon F

I don't think the 928 uses a right and left cylinder head. They both have the same part numbers, don't they? Even the cam towers are the same part numbers, left and right, according to PET. I would really like to hear if this is a viable option! 944 heads are plentiful and relatively cheap.

The valves in the 944 head are shared with the Euro S/S2 engines.

Rich9928p

John, you get it! That is why I posted this. Yes, there is a difference in the 944 head, there is a water passage at the back of the head that protrudes out and would need to be removed for 928 use. That passage could be capped off.

Other than that, I don't see why it couldn't be used. SO I'm asking if it has been done. Or, if someone has tried and there are other reasons why it wouldn't work.

John Struthers

You might get some info out of the resident, head work mad-man from
Texas, Sterling...
I can't recall if it was the Devek or 928 InTL folks who made some comments on this at one time.
Check the Archives
I don't know how Abby's car is running but he did some hellacious looking porting/knife-edging on his wide body engine build-up project ( 2v )-sure would like to see that car someday...

DK

Measure the in/exh valve stem center-to-center distance on one chamber - for both 928 and 944 heads.

special tool

How about 951 heads with heavier springs so you can run crazy cams?

Jon F

There are two major differences that I can see visually between the 944 and the 928 heads. First is the water outlet near the #1 intake port, which looks like it could easily be covered with a plate. Second is the water outlet near the valley that on the 928 attaches to the thermostat housing. The outlets on the 928 are symmetrical front and rear (both look like the right one in the top picture, which has a cover similar to what the 928 has, I believe). I think the 944 head would have to have the part that sticks out near the front chopped off and machined flat to match the rear outlet, then tapped to accept two bolts.

Of course, as DK says, it's important to find out if the heads share the same bore spacing, and of course there's the problem of the volume of the combustion chamber which will affect compression ratio.

Both heads pictured are 944 heads.

Jim Nowak

I have 1985 1/2 944 heads on my 928.

GlenL

And? And?

mark kibort

I know !! thats terrible!!! give us the details!!

I have a set of 84 heads that i will let go cheap. valves and springs are in great shape. no issues, can bolt on or use them for fitting larger valves with.

Also, I wonder about the 944 cams, can they be used or is it an entirely different animal. (probably now that I think about it! i.e firing order)?

mk

Jim Nowak

No, you can't use the 944 cams. I'm using the Devek high lift 2-valve cams.

mark kibort

so, what kind of HP did you get with the 944 heads and high lift 2 valve cams? what intake are you using?

I wonder if the euro cams are as good as the devek cams

MK

Jim Nowak

I'm running Extrued Honed Euro S intake, 104 mm J&E coated pistons, 944 heads, drilled crank, Electromotive Tec II, ETC.... I don't know of the hp or tq because I'm still in the break-in and tuning period. I have to send back my Tec II because its not sending a tach signal out like it should. I will probably not have a whole lot of time to mess with it until I get the tach signal problem fixed. That will entail removing the main unit from the car and sending it back to Electromotive. I imagine the turn around will be a month so maybe in late February or march I'll start tweeking and finish the break-in.

I have another project car that I've been spending time on and it is a load of fun: 1986 560 SEC with an ATI Procharger and 7 psi of boost. It's making 346 RWHP and 400 RWTQ at 5151 rpm. I need to adjust the fuel a little to make more hp and then I am going to bump the pressure up another 5 psi to really start the fun. The car is pretty darn quick and its a ball to drive. Not to mention, it really surprises quite a few people.

mark kibort

so its around a 5.4 liter with euro 2 valve heads. were the 944 combusion chambers smaller too, compared to S4?

sounds like you should get 330 to 350 rear wheel hp. heck, my old 100mm pistons (5liter) with euro 2 valve heads got 292, on the US LJET intake system I would think that the Tec 2 with (what kind of intake , filter set up?)should get 40-50 more hp.

should be a ripper. wish i had at least a GTS 5.4 right now!!
MK