CAM upgrades for 964?

[jfpound]

OK so at least one of the CAM lobes in my stock 964 motor is toasted (strange but true). So if I have to replace the cams anyway, can someone recommend an upgrade? I heards someone say 993ss cams, what are they?

Thanks all.

[Bill Verburg]

There are several good choices. The Webcam 993ss is a safe one, it has increased lift and a bit more duration but the limited overlap is still compatible w/ Motronic.

There are racier but still Motronic compatible cams available as well such as GE 3.2/3.6 or elgin Super C2. Much wilder requires pistons and sometimes engine management chages.

I've seen a solid 270at the rear wheels on a Dyna pac(no tire losses) w/ 993ss, some minor headwork, headers and a custom chip. The headers are the least significant part of the package.

[camgrinder]

The Super C2 is a good one step up.
Its a regrind and the base circle is reduced only .025" , meaning each side of the base circle is reduced .0125"
The lobe in the photo looks typical of a used C2 camshaft.

John

[jfpound]

John, sounds like you're the guy I need to talk to. What change would you expect me to notice after installing the Super C2 cams? Change in torque curve? I assume I should expect more power in a certain RPM range, so what range? Could power go down anywhere? Can you give me a price to regrind my cams to the Super C2 profile? Motor is stock.
Thanks!

[Jim Smolka]

Jeff, Elgin cams may be able to 'save' you cam and then have them ground to the profile you like.

[camgrinder]

you can call me at Elgins for the prices.
650-364-2187

Most the feedback I have recieved has been great for this grind. The power band is similar to stock up to 3000 and then the Super C2 grind increases torque. conservative estimates would be 15/15 torque/HP increase.
I also recommend changing the Valve Springs.
We have a set that is perfect for this grind on the street and go in with the factory seat cup and stock retainer.
We have about 10 new profiles not listed on our web page that I can fax to you.
John

[rich22]

John, I see you are located on the Peninsula. Would the Super C2 pass Cali emissions?

[camgrinder]

I dont have any feedback from the new style testing California does with this profile.
California changed to dyno testing for smog checks recently. What passed before seems to be passing now, but I cant say for sure.
John


* Of course non of the non factory grinds we do are meant for street driven vehicles. *

[ischmitz]

I had a similar issue and John fixed me up with a Super C2 regrind. I have not had the car on a dyno yet but overall I am very pleased. It feels great even on the stock chip. Once I have completed the break-in I will post some numbers.

Elgin seems to be the way to go when you talk to people in the industry.

Ingo

[jfpound]

How necessary is it to refurb or replace the rockers (assuming they look good currently)?

[ischmitz]

You should have them polished at least. Otherwise you run the chance of wearing out the new cam.

Ingo

[Bill Verburg]

There is a break in procedure, for mine (Webcam RS), it was run at an elevated rpm for x mins. Sort of boring but necessary.

[camgrinder]

Im sure a lot of engines get assembled using old rockers arms polished. A light sandpaper accross the pad can sometimes show a defect better as well. I would never recommend using old rocker arms... but if I had to use them over I would paint them with prussian blue and check the pattern. If the pattern covers 90% of the pad and lobe surface it will probably work.
This exercise will also show any misalignment between the lobe and pad of the rocker arm. Because the lobe is not in line with the valve the rocker arms can wear with a taper accross the pad. I have also seen so called "new" rocker arms that had a short pad. Some of the high lift grinds can leave the inside edge of the pad causing failures.
I know the price of new rocker arms have gone up a bunch. Walt at Competition Engineering or Web Cams gan refurbish rocker arms and both work fine.
John