928 Head for reversed air/exhaust flow and short runners
#1
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928 Head for reversed air/exhaust flow and short runners
Hi!
Just wanted to share an idea I got from working on my 928. You probably all know that the 944 engine are based on the 928 and many parts are common. What you maybe don't know is that the left and right head on the 928 are the same cast and only machining differentiate what becomes left or right. I also believe the 944 heads are made from the same casting as the 928 heads, again with some changes to the machining done to the head.
You can remachine two 944 heads to fit a 928 engine.
So my thought is this:
Would it be beneficial for you to have swap sides for intake and exhaust? You would need to make a all new intake manifold under the head where the exhaust manifold is now, and a new ehaust manifold where the intake is now. The benefit as I see it would be a lot of space for and easy access to the turbo. On the other hand, access to the intake manifold would be worse.
I believe you need to do some machining and possibly welding and machining to the head for the water passage. Probably the ear from the water passage can be cut off and welded on the diagonal corner. And of course you need to turn the pistons 180 degrees for the valve pockets. (Some 928 engines are delievered this way, I don't believe you will suffer piston slap.
I am not sure the long piping from the head to the turbo is a problem on the 944, but as you see there is a possible solution if it is. Just thought I would share...
Just wanted to share an idea I got from working on my 928. You probably all know that the 944 engine are based on the 928 and many parts are common. What you maybe don't know is that the left and right head on the 928 are the same cast and only machining differentiate what becomes left or right. I also believe the 944 heads are made from the same casting as the 928 heads, again with some changes to the machining done to the head.
You can remachine two 944 heads to fit a 928 engine.
So my thought is this:
Would it be beneficial for you to have swap sides for intake and exhaust? You would need to make a all new intake manifold under the head where the exhaust manifold is now, and a new ehaust manifold where the intake is now. The benefit as I see it would be a lot of space for and easy access to the turbo. On the other hand, access to the intake manifold would be worse.
I believe you need to do some machining and possibly welding and machining to the head for the water passage. Probably the ear from the water passage can be cut off and welded on the diagonal corner. And of course you need to turn the pistons 180 degrees for the valve pockets. (Some 928 engines are delievered this way, I don't believe you will suffer piston slap.
I am not sure the long piping from the head to the turbo is a problem on the 944, but as you see there is a possible solution if it is. Just thought I would share...
Last edited by Ian928; 10-29-2007 at 12:19 PM.
#3
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bumping this out of curiousity....
You would have to reroute a ton of vac lines, etc. And it wouldn't be cheap!!! But you could put the turbo right on the (custom made) exhaust manifold...
You would have to reroute a ton of vac lines, etc. And it wouldn't be cheap!!! But you could put the turbo right on the (custom made) exhaust manifold...
#5
OK i wanted to do this so when you open the hood all you see is turbo and headers .
BUT the oil drains for the head are on exhaust/low side this is a massive problem .
BUT the oil drains for the head are on exhaust/low side this is a massive problem .
#6
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The 928 heads(8v and/or 16v) flow way worse than the 944/951/968 heads. They may have the same bolt pattern and coolant passages but they don't flow worth crap. A 968 head is way better than the best 16v 928 head, I think its the GTS head.
#7
so evil while your at it how about ranking the other 944 heads I have an orphaned S head that i'm thinkiing of using for my 3.1 turbo but i have to mod the coolant passage i wonder weather i could change it over to S2 for resonable dollars .
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#8
If you wanted to do this you could probably have a custom 944 head and cam made alot easier. Have a cam made to open the exhaust valves on intake and intake valves on exhaust, then do ALOT of port work and bigger valves.
#9
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A few months ago, someone posted pics of using a 928 head exactly as described...
I can't seem to find the thread now though.
Rogue
I can't seem to find the thread now though.
Rogue
#10
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#11
I think just swapping the valves(custom seats) and re timing the cams porting the exhaust stainles sleeves into the old inlet ports would get you there but it would take some commitment
#12
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Two things.
1. It can be done and it makes for an easy swap BUT performance wise, Its as good as sticking a screw driver in youe eye.
c. Gt37vgt - Sell your 944 S head and buy a S2 or 968 head. It will be way easier than modding your 944s to work with the 3ltr block and you don't have to change valve sizes etc.. to get it to flow of the bigger heads.
1. It can be done and it makes for an easy swap BUT performance wise, Its as good as sticking a screw driver in youe eye.
c. Gt37vgt - Sell your 944 S head and buy a S2 or 968 head. It will be way easier than modding your 944s to work with the 3ltr block and you don't have to change valve sizes etc.. to get it to flow of the bigger heads.
#13
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Two things.
1. It can be done and it makes for an easy swap BUT performance wise, Its as good as sticking a screw driver in youe eye.
c. Gt37vgt - Sell your 944 S head and buy a S2 or 968 head. It will be way easier than modding your 944s to work with the 3ltr block and you don't have to change valve sizes etc.. to get it to flow of the bigger heads.
1. It can be done and it makes for an easy swap BUT performance wise, Its as good as sticking a screw driver in youe eye.
c. Gt37vgt - Sell your 944 S head and buy a S2 or 968 head. It will be way easier than modding your 944s to work with the 3ltr block and you don't have to change valve sizes etc.. to get it to flow of the bigger heads.
#15
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I don't think this would work at all since with a 180° rotated head, the cambox will now be almost vertical, more towards the middle of the engine bay and much higher. It won't let the hood close. The standard 944 engine arrangement was chosen just to fit the engine under the hood.
Of course, the hood can be modified.
But good thinking - this may be a great idea for someone looking to build an off-the-wall custom turbo car. We need more original ideas like this.
Of course, the hood can be modified.
But good thinking - this may be a great idea for someone looking to build an off-the-wall custom turbo car. We need more original ideas like this.