David J. Harrington

Does anyone know if the S2's block cylinders are siamesed together as in the 968?

Thanks,
Dave

aka 951

I believe they are the same part number

Julian Allen

They are the same casting. The difference is limited to the addition of piston squirters on the 968 machined blocks, these are not present on the S2 blocks.

Danno

Anyone have a photo of the 968's piston squirters? Can they be retro-fitted to the S2's block?

951and944S

Tapping into the girdle's oil supply channel with self designed squirters placed strategiclly to avoid crankshaft rotation should be no problem,

but are the nozzle ends an orfice controlled open end supply or a flattened end providing flow control and the squirting affect..

Also, since the oil will be performing this extra task of cooling the pistons more than simple splash and heat transferred through the wall to the coolant, is another/larger oil cooler necessary to cope with potential higher temps...?

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Danno

I would also think that a pressure valve at the nozzle would be needed. So that they only open at high-pressure (say 4-bar & above). That way, you can maintain decent oil-pressure at idle and the squirters aren't dumping what precious little oil-pressure you have out onto pistons that aren't even stressed at the moment.

aka 951

I think its pretty standard procedure when building up a 944 motor. I believe Garrity does this on his performance rebuilds.

951and944S

Hmmmm, there's been a rash of failure on GM Vortec type poppet valve fuel delivey system, not so much with the poppet valves but with a leaking FPR that comes as part of the assembly.
So, these are avaliable to me for testing the feasabiliy to use a poppet type valve, I'll try to get some info on what pressure they are set to open.
They are also made out of some type of poly material that's obviously resistant to fuel, and this feature would also serve well for vibration since they should not be prone to cracking..

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Turbo Fanatic

Danno, I just picked up a new 3.0 968 block. The 968 block has in addition to the piston oil squirters vents in the webbing of the crankcase, so that when one piston is going down, the air it is displacing is routed to the adjacent cylinder in which the piston is going up. I am trying to get part number for the squirters, as block is bare, but brand spankin new! The tech info I have, details a pressure relief valve in each squirter. PET does not list these. Both Garrity, and JME retrofit 2.5 and 3.0 S2 blocks for squirters, but it appears they use squirters from
930. Those may indeed be the correct one for the 968 block, but I can confirm that. I will try to snap some pics this weekend and upload or I can email em to you. Let me know.
thanks
James Thomas

951and944S

Correction, the passage re. the girlde's oil supply as I posted above wouldn't be feasible, since that channel is the suction from the oil pickup to the pump's suction side.

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