sherry66

Hi ,would anyone know if its possible to run 968 cams in an S2 head with the S2 tensioner ?
From my understanding , with the different lift on the 968 cam , midrange would be missing without the varocam , but top end power improved which would be fine as the engine is destined for my track car.
Does anyone have any experience of this?
Thanks

ramius665

You're close but not spot on. S2 cams will physically fit the 968 head but the S2 tensioner cannot be used because it won't bolt up correctly. What you need to do is source a tensioner from a 928 S4 which had the same tensioner layout as the 968 heads. That will allow you to run S2 cams without variocam.

V2Rocket

Aaron...that's not right...
The 928S4 chain tensioner is the same part as used on the 944S/944S2.
I have a set of 928S4 heads on my shelf, and guess what fits...

I would guess you could use the 968 cams as a pair in the 944 head but they are top-end cams that only had a nice midrange because of the advanced VarioCam timing.
I think they would make a dog out of the S2.

Luckily, 968 cams are very valuable and you could probably sell them for enough money to buy a VEMS setup...which with very little set up/tuning time is shown to get an S2 to 208hp at the wheels...

https://rennlist.com/forums/924-931-...under-wot.html

91K-Man

968 cams have a smaller gear for the chains, so they will not work in a 944 S2 head. Smaller gears so the vario can do its thing.

ramius665

Interesting. David Raines was quoted with using a 928 S4 tensioner in his 16V 968 turbo builds when he replaced the Variocam. So if I understand your post correctly, the 928 S4 tensioner is exactly the same as the 944 S2 tensioner? I was under the impression it used the additional mounting bosses on the 968 head. Good to know.

Here's the article where David discusses using the 928 S4 tensioner:
Powerhaus 968 Turbo

V2Rocket

Yea...the entire 928S4 head is almost identical to the 944S/S2 head, so it makes sense the chain tensioner would be too.

S/S2/S4 is the regular 2-bolt tensioner which should bolt up to the 968 head...the Variocam specific tensioner has the 3rd bolt hole on the opposite side as a brace.

91K-Man

Each tensioner is different,bolt patterns are not same.

fortysixandtwo

​​​​​​​This is doable without a ton of effort. What's needed is to build up some aluminum to the number 2 cylinder's spark plug tower to provide material for drilling/tapping the vario-cam actuator's front mounting bolt. After that, the 968 cam cover bolts directly onto the S2 head.

blade7

Are you on commission ?

V2Rocket

No...it's just that good.
I paid more for my VEMS setup than I did for my Subaru

Jay Wellwood

There is a guy over on the 928 board here who spent a considerable amount of time, effort and $$$ adapting the 968 chain tensioner to his 928.

http://www.928sg.com

333pg333

Why not avoid all this and go with front mounted cam drives and do away with the chain altogether. Cat Cams in the UK have some cams and lifters for the twin cam motor already.

odonnell

Same reason for me posting about MS being a mod that's worth $1000 before almost anything else. It's such a good upgrade for an 80s EFI car.