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944 S in SC 
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To make the S car competitive, consideration is being given to making the cam shaft "free" for this model. This will allow the model to become more competitive by producing more power and torque, and lessening the need and expense to make the care meet the minimum weight of 2500 Lbs.

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Dave Derecola
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Thu Oct 23, 2014 6:46 pm
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Great idea. One other consideration that may be less expensive would be to allow S2 or 968 intake manifolds. I can't find anyone reporting numbers, but it is generally considered an upgrade (though I take that cum grano salis).


Fri Oct 24, 2014 6:07 am
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67King wrote:
Great idea. One other consideration that may be less expensive would be to allow S2 or 968 intake manifolds. I can't find anyone reporting numbers, but it is generally considered an upgrade (though I take that cum grano salis).


Thanks. I do not recall ever having an S run in the series, but I do see them in SCCA. Would be good for SC if we could get some to swing our way.

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Fri Oct 24, 2014 8:18 am
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I know of one guy who run at Summit Point a couple of times. There isn't much info on him on Rennpoints other than those two events. His times and finishing position do indicate that the car wasn't all that competitive (obviously there could be many other reasons for that than just the class allowances for the car).

Do you have a timeframe for when the potential change would be decided? Looking to yank the turbo out over the winter and go with something more reliable.


Mon Oct 27, 2014 9:36 am
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67King wrote:
I know of one guy who run at Summit Point a couple of times. There isn't much info on him on Rennpoints other than those two events. His times and finishing position do indicate that the car wasn't all that competitive (obviously there could be many other reasons for that than just the class allowances for the car).

Do you have a timeframe for when the potential change would be decided? Looking to yank the turbo out over the winter and go with something more reliable.


Promised to have 2015 rules to PCA by end of next month. There is some debate just how much can be gained from these mods.

Maybe be more of a reliability improvement. In addition to the concern that 8V 944s have with regard to timing belt maintenance, 16V 944 owners, such as 944S, must also be concerned with the maintenance of the timing chain and tensioner. On the 8V 944s, valve timing for both the intake and exhaust valves is accomplished by a single overhead camshaft. The 16V 944s, have two camshafts, one for the intake valves and one for the exhaust valves. On these cars, the exhaust valve camshaft is driven by a camshaft sprocket directly from the timing belt, identical to the 8V cars. However, the exhaust and intake camshafts have a toothed gear located near the center of the shaft. A chain between the exhaust and intake cam allows the exhaust camshaft to drive the intake camshaft. The drive chain tension is maintained by an oil fed tensioner. Over time, the tensioner will eventually wear out. The tensioner itself seems to be fairly reliable until around 130,000 miles. However, many 16V owners have experienced failures related to other tensioner components a just over 100,000 miles. Most of these failures can be attributed to failures of the J-Tube oil supply pipe or to the plastic guide rails on the tensioner.

Mechanically and maintenance-wise, moving the throttle body to the front of the engine instead of that troublesome plastic piping, extra boot connections and clamps (unnecessary points of vacuum leaks) is a change worth making. It is possible that coupled with the throttle body from the S2/968 (may be larger diameter ), it could enable more power.

Also, the piston to valve clearance is so close on the 944S already due to the high compression pistons, that there isn't a whole lot of room for a valve lift increase (safety margin of .030 is the norm for a race engine due to float and overrun on downshifts) and for much of the same reasons, going far with duration either may not work.

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Mon Oct 27, 2014 10:09 am
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Most of the failures from what I've seen are due to the polymeric pad on the secondary chain tensioner wearing down and not being replaced. Unfortunately when it goes, it often breaks the mount on the head (the 968's design addressed that). But trust me, anything has got to be more reliable than a turbo. There is just so much that can go wrong.......and added plumbing? Sheesh.


Mon Oct 27, 2014 10:07 pm
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Director wrote:
Also, the piston to valve clearance is so close on the 944S already due to the high compression pistons, that there isn't a whole lot of room for a valve lift increase (safety margin of .030 is the norm for a race engine due to float and overrun on downshifts) and for much of the same reasons, going far with duration either may not work.


Peak lift shouldn't be a concern. It is really the closing ramp. Just looking at the intake, peak lift is 28 degrees ABDC, the piston will be 66.7mm below the deck face. There is tons of room there, probably nearly 60mm after accounting for chamber shape and head gasket.


Thu Oct 30, 2014 9:49 am
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67King wrote:
Director wrote:
Also, the piston to valve clearance is so close on the 944S already due to the high compression pistons, that there isn't a whole lot of room for a valve lift increase (safety margin of .030 is the norm for a race engine due to float and overrun on downshifts) and for much of the same reasons, going far with duration either may not work.


Peak lift shouldn't be a concern. It is really the closing ramp. Just looking at the intake, peak lift is 28 degrees ABDC, the piston will be 66.7mm below the deck face. There is tons of room there, probably nearly 60mm after accounting for chamber shape and head gasket.


Know anyone selling camshafts off the shelf for the 944S?

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Mon Nov 03, 2014 2:57 pm
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Director wrote:
67King wrote:
Director wrote:
Also, the piston to valve clearance is so close on the 944S already due to the high compression pistons, that there isn't a whole lot of room for a valve lift increase (safety margin of .030 is the norm for a race engine due to float and overrun on downshifts) and for much of the same reasons, going far with duration either may not work.


Peak lift shouldn't be a concern. It is really the closing ramp. Just looking at the intake, peak lift is 28 degrees ABDC, the piston will be 66.7mm below the deck face. There is tons of room there, probably nearly 60mm after accounting for chamber shape and head gasket.


Know anyone selling camshafts off the shelf for the 944S?


No, I was assuming a regrind would be how folks would typically change the profiles. I believe Michael Mount has at various points had billet blanks made, which would give even greater room.


Fri Nov 07, 2014 6:48 am
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Spoke to MM, and he could provide Cup drivers with camshafts for the S model that would bump up the power. He also would think the S2 intake would allow a further boost in power, and be a logical mate with the cams. A cams/intake package would allow the increased air “in”, but would need to be mated with a suitable exhaust header.


The 968 intake may be overkill given the manifold’s larger inlet ports, and would require rather extensive porting of the S inlet ports to match. All or any of these mods would require re-tuning.

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Sat Nov 08, 2014 4:14 pm
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