Change to MFI pump on 2.0 s motor

[kenikh]

Low compression on high overlap S cams...not great for performance

[Frankr]

Looks like I may have barely used set of 2.2S P&Cs for sale in the future. Damm. Another expensive Porsche lesson. Not the first.

[kenikh]

Looks like I may have barely Z set of 2.2S P&Cs for sale in the future. Damm. Another expensive Porsche lesson. Not the first.

I have some 85mm JEs that are cut for 2L heads. Brand new. Bore your 2.2 cylinders...done.

[YTNUKLR]

I have some used 2.2/2.4 Biral cylinders that would be great candidates for boring, rather than re-boring nice cylinders

[SIMI BOB]

Frankr,
I do not think you have to worry about valves hitting the pistons, the dome on the 2.2S piston is much smaller than the 2.0. What you will have to deal with is that you had to cut your 2.0 heads to mate with the 2.2 cylinders. You may be able to find a custom 80MM cylinders that will interface with the 2.2 cut head and is fitted with an "S" type piston. I asked Walt at CE if he could weld up my 2.0 heads, and he said he had never done that but it was probably possible.
If you don't have Wayne Dempseys book, I think it would help you out to get it. Page 201 has the specs for '65 thru '73 heads, and you will see that the 2.0S had 45x39 valves and 36x35 ports. All of the 70 thru 73 heads had 46x40 valves, but the T and E heads have 32x32 ports and the S has 36x35 ports. Walt found a good set of 2.2 heads and ported them to 2.2S specs, but the price was over 2K. Also, if you look at the post I referenced above, the consensus was that the different valve angle was of no consequence, just bolt on the stock 2.0 parts.
Bob B

[kenikh]

Best bet here really is a set of 84mm JEs @ 9.5:1 using 2.0 head geometry.

No need to weld the heads. Henry @ Supertec does sell a spacer kit to fit cut heads to earlier cylinders, but they are about $120.

Just skip the complexity, get some JEs, recoup your costs by selling the Mahle pistons.

[Frankr]

Frankr,
I do not think you have to worry about valves hitting the pistons, the dome on the 2.2S piston is much smaller than the 2.0. What you will have to deal with is that you had to cut your 2.0 heads to mate with the 2.2 cylinders. You may be able to find a custom 80MM cylinders that will interface with the 2.2 cut head and is fitted with an "S" type piston. I asked Walt at CE if he could weld up my 2.0 heads, and he said he had never done that but it was probably possible.
If you don't have Wayne Dempseys book, I think it would help you out to get it. Page 201 has the specs for '65 thru '73 heads, and you will see that the 2.0S had 45x39 valves and 36x35 ports. All of the 70 thru 73 heads had 46x40 valves, but the T and E heads have 32x32 ports and the S has 36x35 ports. Walt found a good set of 2.2 heads and ported them to 2.2S specs, but the price was over 2K. Also, if you look at the post I referenced above, the consensus was that the different valve angle was of no consequence, just bolt on the stock 2.0 parts.
Bob B

I have to look at my bills on the job. I think we did the larger valves too. BTW I used to live in Simi back in the 70's. Was just back for the Rose Bowl a year ago. Lots of growth there. Still windy.

[SIMI BOB]

Frankr,
Looks like Kenikh has the best idea for your situation. You still end up with a 2.2S, but make sure JE knows that you are using 2.0S heads, and check your valve clearance to the piston upon assembly.
I went with the 2.2S heads because I believe the combustion chamber is a little more forgiving with the crappy gas you can buy today. Sure miss that Chevron "White Pump" 104 octane gas.
Let us know what you decide, and how it runs when you are done.
Bob B

[Frankr]

One more question. If I go back to 2.0 P&Cs will the fact that the heads were cut a bit to fit the 2.2 pistons be an issue?

[kenikh]

One more question. If I go back to 2.0 P&Cs will the fact that the heads were cut a bit to fit the 2.2 pistons be an issue?

Huge. You can't even fit 2.0 cylinders now. Totally different mating surface. I went into more detail on this in a previous post.