custom AN cam lines
 

I'm making some custom AN cam oil lines.

would it be OK to use this bolt for the oil pressure sensor that'd been modified for AN fitting, or should I get a metric AN adapter for the stock one?

the hole size and placement are different, so I was a bit worried.

https://www.dropbox.com/s/7hjxvd0c9j...jpg?dl=0&raw=1

Wouldn't be that hard to grind a groove in your adapter, just to be sure.

I would like to see you finished product.

Use an adapter. That hole and groove are designed to line up with a very small hole in the sender.

Actually - You could use it. . . . But .. .. The hole is there as a restrictor to fill a chamber and to emulate what pressure a bearing sees. Your bolt would feed Full Line pressure and you'd have a reading that's not actual to the calibration of the sensor.
Not running Carrera tensioners?

hmm, I probably want my oil pressure gauge to be correct tho? :) the AN adapter is cheap enough, just thought it'd be nice to use the all in one piece.

No, Ive done enough research to be confident with the 930 thin boss tensioners (with stoppers) and thicker Carrera idler arms. I recently rebuild the tensioners too:
http://forums.pelicanparts.com/911-engine-rebuilding-forum/901641-3-2ss-78sc-2.html#post9004639

Would there be a market for a custom fitting that would mimic the factory fitting and have an AN fitting on the other for running braided lines?

David

My racecar engine uses non-Carrera tensioners and I replaced the gauges with Autometer stuff. So I ditched the oil pressure sender "block" and the factory gauge sender and that allows me to use AN-4 hose for the cam housing oil feed lines

I replaced the fittings at the engine case with M12x1.00 (not sure on this, have to check) male to AN-4 male adapter fitting. I sealed it with stat-o-seal rubber-aluminum sealing rings. At the cam housings I used metric banjo adapters that are M12 for the banjo bolt and have male AN-4 fittings coming off the banjo body.

https://www.pegasusautoracing.com/productdetails.asp?RecID=6734

I assume the oil pressure sender unit gives an actual value vs the oil pressure switch is just for a warning light?

Im gong to keep the sender block so I can keep my instrument cluster as-is. I can get a straight metric female to -4 male off the block.

I need to look up these "stat-o-seal rubber-aluminum sealing rings", are they required for all AN fittings on engine case?

For the cam housings, I have already tapped the 964 heads for -4 fittings, so I was going to use an 90 deg swivel fitting there. This should work OK?

https://www.dropbox.com/s/6iwb6x8s7f...jpg?dl=0&raw=1
https://www.dropbox.com/s/ky24fhtclu...jpg?dl=0&raw=1

Yep that's correct regarding the oil pressure sender. It is a pressure transducer which provides variable output to the gauge depending on pressure. The oil warning light is just a switch (normally closed) that opens when it sees pressure. The oil warning switch is sorta pointless IMO in that it's pressure/switching threshold is so low (like less than 5 psi I believe) that you're already in trouble if that light is coming on when you don't want it to be on

The stat-o-seal is a rubber-aluminum combination. Not necessary for all fittings. I simply used it because it fits the fitting I used. They look like this


http://forums.pelicanparts.com/uploa...1458664359.jpg

The 90 degree hose end will work good on that fitting you installed in the cam housing. I left the original Porsche adapter fitting on the cam housing to maintain the so-called restriction (or lack thereof) that is placed there beneath the banjo connection. The debate continues as to whether or not restricting oil flow to the cam housings is a good thing or not. Here's just a few of the threads on the amount of oil going to the cam housing

http://forums.pelicanparts.com/porsche-911-technical-forum/202592-cam-oil-restrictor-fitting-why.html

http://forums.pelicanparts.com/911-engine-rebuilding-forum/733469-oil-cam-restrictor-rockers-zddp.html

http://forums.pelicanparts.com/911-engine-rebuilding-forum/335776-3-0-liter-upgrade-horsepower.html

It would seem since you have actual 964 cam housings, your restriction lies beneath your new fitting.

Thanks for those links, I've read most of them.. you're saying the actual oil inlet, as seen here will cause the reduced flow by design in 964 cam tower? Without the need for the adapter with the smaller inlet?

https://www.dropbox.com/s/0vloatkpi2...jpg?dl=0&raw=1

Well its not actually the hole in the cam housing feed tube. On the older cam housings its the fitting that screws into that inlet. In this thread the picture shown in post #17 has the newer 964 cam housing's transfer tube sitting next to the older 911 inlet fitting.

http://forums.pelicanparts.com/911-engine-rebuilding-forum/733469-oil-cam-restrictor-rockers-zddp.html#post7269727

The transfer tube is part #16 in the parts diagram

http://forums.pelicanparts.com/uploa...1458832699.jpg

I have to assume that tube has been removed from your 964 housing in order to adapt it for use in the older 911 engine configuration? That tube is normally used to connect with a bridge piece #21 that brings oil from the crankcase into the chain case. Before the oil gets to the cam housing, it feeds the 964 chain tensioner. This is how the 964/993 3.6 engine does without the external oil lines for the cam housings and Carrera chain tensioners.

http://forums.pelicanparts.com/uploa...1458833014.jpg

So I have to correct myself and say that your "restriction" is determined by whatever fitting you use in that hole, since I was incorrect in saying the transfer tube acts as your restrictor.

The updated old restrictor is a lot smaller and that's where the debate lies. You can see the distinct change in size between the old fitting and the updated old fitting in this post

http://forums.pelicanparts.com/porsche-911-technical-forum/202592-cam-oil-restrictor-fitting-why.html#post1720758

Great info, thanks Kevin!

Im definitely running unrestricted then, with the potential for less cooling through the piston squirters, it seems. Im not sure there is an easy way to add this restriction, if I so choose. The cam towers were modified to be used with those -4 fittings, they were tapped specifically for that purpose. Im not sure what they looked like before (curious, will try to find a pic).

The fitting would allow for full flow, I'd think from looking at it's design. The restriction should only be in the -4 lines.

https://www.dropbox.com/s/tp1dxw21v5...jpg?dl=0&raw=1

KTL, do you have any specifics on the hole size of the restricted pieces? Seems one person averaged the middle point to be ~4.5mm
http://forums.pelicanparts.com/911-engine-rebuilding-forum/733469-oil-cam-restrictor-rockers-zddp-3.html#post7406754

Im thinking I can use a AN-3 line instead, which would provide a similar (middle-ground) restriction of 4.75mm (AN-3) vs the 6.35mm (AN-4) lines I was going to create.

I can't really tell from the pics, but it sounds like the new restriction is closer to ~2mm?

Your adapter will work fine from an oil pressure indication standpoint. The PSI it sees will be the same whether you have a 1/16" hole or a 1/2" hole. The reason oil pressure transducers and switches have tiny holes in them is in case the can blows off the pressure in the galley won't go to zero. The tiny hole restricts the flow exiting the system so there's still pressure at the bearings so you have time to shut it down when you see the oil psi go to zero and the idiot light comes on. So for that reason it's wise to keep the restriction. There's probably some of this same logic involved in the design of the restrictors to the cam oil lines. If a hose blows you lose the pressure to the top end but save the lower end.

finally back at this, after a little hiatus (work and life, you know the drill).

I cannot user the original banjo style fitting on cam tower end, as they were tapped out for the AN fittings. I wanted to use a AN metric adapter off the pressure sender block, since the other tube in the first pic will give me incorrect pressure readings.

I don think there will be much clearance from the sender's tube and the AN adapter! So I either have to ditch the sender unit and find another way to get a pressure reading for my stock gauge, or modify the original pipe; cutting it at the rubber portion and making an AN line from there.

Thoughts or questions?

The older motors had the oil pressure sender mounted on the front of the case, instead of the oil pressure warning light switch. Would that be an option to replace the oil pressure warning light with the pressure sender? Of course my '71 doesn't have an oil pressure warning light.

I have custom cam lines myself, no restrictor so far. Still unsure if I should or not. Oil pressure sender moved to the thermostat housing (no thermostat inside), works fine:

http://forums.pelicanparts.com/uploa...1471515446.jpg

http://forums.pelicanparts.com/uploa...1471515457.jpg

great ideas about moving things around the pressure circuit.

I can do without the warning light and will think about moving it there.

also will look to see if I can get things up in the thermostat blockoff im using from the 965. there are two plugs and I would need to tap the larger M18 plug to accept the pressure sender.

http://forums.pelicanparts.com/porsche-911-technical-forum/904523-964-turbo-t-stat-wanna-block-off-senders.html#post9078869

Maybe I can use the JB racing part 131-035 which is an oil pressure adapter. Im not sure of its thread. The M12 on the 964 t-stat Im using is M12x1.5. But I could see putting the pressure sender and its block off the t-stat is this fits.

otherwise, I'll likely remove the idiot light and put the sender block there.

Roland, how do you control the pressure the sender sees? Per comments above, it's supposed to be calibrated to what a bearing would see.