Two sets of 964 cams from Webcam.......
 

I had the last two motors (3.0 liters) rebuilt last year and this year with 964 cams from Webcam and set @ 1.26 mm. This is the value written on their spec sheets from Webcam. Unless you have better knowledge and experience than the cam manufacturer/supplier why go against their specification? Set it as specified and you will be happy.

Tony

I set mine to 1.4. I haven't dyno'd it yet, though it feels nice and linear straight up to 6820 or whatever the later factory redline was.

The 1.8mm spec came from the expert who reground my cams, John Daugherty of DRC. This is the reason I didn't question it until after the engine was assembled and broken in. I tried to contact him for additional info to no avail. I'm curious if his rationale for advancing the timing to 1.8 is based on dyno numbers or other measurable data.

DC20 or 21 Use in a 3.2?
 

Does anyone have experience with a "stock" 3.2 (intake, ECU & Exhaust) and either John's DC20 or 21?

I have a stock 3.2 that needs a full rebuild and was planning a 3.4 twin-plug, but can't find an Andial splitter anywhere. Long story short, I can't drive the car every day here in DC unless it has the stock exhaust & emissions.

John recommended the DC21 for this application.

If, however, I decide to build a hotter 3.2 or single-plug 3.4 w/ JE pistons and enough relief for higher lift cams, wondering if the 21's too much cam for the street?

I had a 2.7RS motor that I absolutely loved to just run in the 3-6000 RPM range. It idled smoothly w/ MFI but ran right up to 7300 at the drop of a hat. The 3.2's a bit of a wheezer over 5k, and that's what prompted the DC21 selection. Bruce Anderson always recommended "wilder" cams the larger the displacement, and I'm very open to the 20 or 21. Just curious to hear how any of you who have one have found it on the street.

Thanks,
John

I have the exact same question and I too, have not heard a response from John Daugherty. In lack of response, I set the "964" cams he reground for me to the factory 1.26 mm instead of the 1.8mm listed on the label that came with the reground cams.

I did look at the other cams mentioned in this and other threads and the "specs" listed on the DRC website indicate that "964" cams should be set at 1.26mm and one of the similar cams (DC 19) to be set at 1.8-2.0 mm.

I had a set of cams reground by John in June and he turned them around very fast. These were a SC/Carrera cam reground to 964. They were sent out to him & back in my hands in just over three weeks. Not bad considering i'm in IL sending them to him in CA. Point of me mentioning this is the cams came from him with the standard 1.26mm timing spec. No mention whatsoever of 1.8mm

I've also used his DC-20 (also referred to as "Super C2") cams in a basically stock 3.2, besides racing exhaust & chip, in my former '87 Carrera. I found that the recommended 2.2mm-2.4mm timing spec couldn't be achieved due to piston-valve clearance being closer than I was comfortable with. So I backed off the timing spec to 1.85mm in order to get suitable clearance.

http://forums.pelicanparts.com/911-engine-rebuilding-forum/351742-cam-timing-dc20s.html#post3328568
The DC-20 performs nicely in terms of pulling hard to redline. But the cam modification didn't really show a drastic change in terms of power. I think its a marginal cam choice for a stock 3.2. The DC-20 wants higher compression to ensure there's not a loss of lower rpm grunt, according to Dougherty. The DC-20 is still in the engine which is now running a stock exhaust (with cat) and factory ECU chip. Performs OK on the street and on the track with the new owner, who is local to me & I with who I have become good friends.

If I were to do it all over again for a stock engine, i'd get a 964 profile and call it good. It makes good sense to go with the 964 since it's a proven improvement and why not if you have to regrind pitted cams anyway. If you want to go more than that, i'd go with the DC-19, not the DC-20. Based on the specs that Dougherty lists for the DC-19, it looks like it is similar to the WebCam 20/21. The 20/21 is another cam that people with 3.0 & 3.2 stock engines have indicated is a proven improvement.

I always send the 964 cams out with a sticker showing 1.26mm.
I have told customers 1.4mm, 1.6mm and even 1.8mm. All depends on what they are looking for and the combination. 1.26mm puts the cams in a couple degrees retarded from straight up. 1.8mm puts them in advanced.
Telling the customer he can use 1.8mm is usually a response to their concern about low speed power. I try and clarify this with , "you will lose a little on the top by advancing the cams".
Also, compression ratio plays a big part in this. Using a 964 cam in a 3.0 with 8.5-1 compression will need to be advanced. DC15 is a better choice. If you run the engine at high altitudes with low air density, you would also benefit from advancing the cams.

Since you are going single plug (and I assume less compression) I would go with the 993-SS.
993-SS is a little smaller than the DC21. Same intake profile with 4 degrees less exhaust profile.
http://forums.pelicanparts.com/porsche-911-technical-forum/523227-can-964-super-sport-camshaft-used-cis-motronic.html#post5153241

John thank you for weighing in on this; good to get the info straight from the source. For the record, the box you sent me with my 964 cams has a "1.8" sticker on it. I guess I should've asked more questions before installation. Regardless, in light of your explanation above, I feel setting my timing back to 1.26 was the right choice. I like the way my car runs much better now.

Good deal. I wonder why we put the 1.8mm sticker on it. Any chance you have the original invoice number?

Thanks John
 

Thanks John for clarifying. JE sells 9.5:1, 10.5:1, and 11.5:1. I can get 93 gas here readily and was hoping to be able to run the closer to Euro-spec 10.5's, but may play it safe w/ the 9.5's.

Sounds like you would recommend the lower ones that are closer to stock if I stay single-plug? Still hoping to find someone who will part w/ a splitter...Oh, and thanks for that dyno sheet! awesome although I didn't need any more reason to want to get my rebuild started ;)

Best,
John

You see, this is what was confusing to me. This is a picture of the sticker that came with my 964 cams. Fortunately, I guessed to set them at 1.26mm.

http://forums.pelicanparts.com/uploa...1443674880.jpg

John, thank you for chiming in and giving a definitive answer to the question lurking in the back of my mind since installing these cams. P.S. I have another set that I will be sending you for another 3.2.

Here you go....

http://forums.pelicanparts.com/uploa...1443681581.jpg

Sure looks like the wrong stickers on both of those. John's for sure after looking up the build specs (old emails). I don't have any info other than the invoice on yours TT.

I agree on playing it safe at 9.5-1. Never know what you really get for octane at the pump.

I sent my cams to Dema Elgin, I told him what I was doing and what I wanted out of my engine when I was finished. What I got back was a fresh pair of reground & polished cams with a 1.26mm recommendation. I haven't finished breaking in my engine yet but I'm on my way. I got everything I was hoping for, better punch at lower speeds, quicker response at throttle input. What I wasn't expecting but pleasantly surprised is a thrust when at 5000 rpm and an extra surge of acceleration as the rpm's climb.

Do you mine sharing the spec of these Elgin cams and the motor that's it's in?

I have a 3.2 with twin plug and euro pistons. I'm looking into a lttile more low end as well as the top hopefully to 7k. Any idea what your motor is making? I hope to get 260hp with no loss in the low end. Would these cams get me there?

964 Cams
 

My 3.3SS engine uses 964 cams which I timed at 1.3mm. This engine falls into the "FrankenPorsche" category as it uses 10.5 Mahle pistons, KN Engineering slip fit cylinders, Carrera twin plug heads, an early SC airbox with the large ports and runners and the CIS backdated to mimic the 73.5 system. Ignition is by Electromotive XDi. The bottom line is that it works well and runs perfectly on 91 or 93 octane pump gas. Bottom end and midrange torque is good and it pulls quite strongly up to the ignition cut out at 7500.

I've had a nice result from WebCam 20/21 set at 2.2. I've dynoed at 275hp/260tqin my 3.4 with good drivability and passing California smog checks.

Hello Steve

Nice numbers. I would be more than happy if I can get 275/260 without any lost of low end. What was the CR? JE or Mahle slugs?

I'm curious why the 3.2 has such a low redline? My old 3.3 930 revved higher. What are the limitation? Valve train? Rods?

Thanks for posting