964 cam timing in a 3.2
 

I'm running 964 profile cams in my 3.2 combined with a Wong chip, George's headers and M&K GT3 muffler. Stock heads and 9.5:1 compression. On the recommendation of DRC I set the cam timing at 1.8mm. I talked with Steve Wong who recommended the stock setting of 1.1. Supposedly the advanced setting of 1.8 is supposed to provide a more torquey character to the engine. I'm in a bit of a quandary now as I have two different recommendations from two well regarded experts in their fields. I have to admit, I'm a little disappointed in this engine's top end performance. It feels soft over 5k and I'm missing that top end "rush" to redline. Now I'm considering resetting the timing to 1.1 for a snappier top end. Looking for opinions from those of you who have a similar setup.... Am I splitting hairs here?

Spec on the C2 cam is 1.25 with the window 1.1 to 1.4. I have set them as high as 2.0 on valve relief pistons like JE but on Carrera pistons, make sure you have valve room at 1.8.
Bruce

I set my 964 cams to 1.25, and my otherwise stock 3.2 pulls strong to redline even with the stock exhaust. I do notice the idle is a tad more lumpy though. Can't wait to upgrade the exhaust and get a chip from Steve.

I carefully set my 964 cams at 1.26mm. It seems a good mid point for all around use and it idles perfectly smooth.

This is in a 3.3 liter turbo motor with B&B headers, gutted B&B muffler, CIS Flowtech modified fuel head for around 20% more fuel, brand new Mahle pistons and cylinders and rebuilt cylinder 930 heads with ported 40mm intake ports.
With 7:1 compression and the slow reacting throttle response of k-jetronic mechanical injection it doesn't have much low end torque anyway. From 3500rpm on up it goes pretty good.

I am running a DRC 964 grind in my 3.2 A cat bypass and a Steve Wong chip are the only non stock additions. As per John's written recommendations, and with a double check email to him, I set the cam timing at 1.8mm. It idles about the same as before and the powerband is similar to stock - the usual rush above 4000 to redline but I find it stronger throughout. So for me, 1.8 works great.

I'm in the same boat here. I bought and just installed 964 cams in the track car 3.2 and started out with the 1.8mm lift at overlap per the sticker on the box indicated. This seemed funny to me, so I looked it up and ended up setting them to the stock 964 timing of 1.26mm at overlap. I spent the time to get them really close (had to jump chain teeth on the cam chain sprockets). In any event, I am for good or bad running ours at 1.26mm lift.

I tried to contact John Daugherty, but haven't yet heard back from him concerning where to set these cams. Our original email communications showed 1.26mm, but the sticker on the box with the cams stated 1.8mm.


Our car is a 914-6 with headers. I haven't gotten a response from Steve Wong on a chip request I sent to him a few weeks ago.

I'm doing this soon, subscribe

I have a 3.0 that is stock except for 964 cams and exhaust and I set to 1.9mm with no clearance issues. Remember that if you use a new timing chain it will stretch a bit and retard your timing over time. But that being said, I love the way the 964 cam feels advanced with all the torque down low and still pulls like a mad past 4k. I just wanted more grunt below 3 as well.

964 cams........
 

I built a 3.3SS engine a while back using 964 cams. I set the cam timing at 1.3 for each camshaft. End result was an engine with good bottom end torque (displacement and compression) and one that pulls like a freight train on top end (big port Carrera heads). Very happy with the setup.

I just had a 3.2 stock engine on the dyno. I changed the timing from 1.1 to 1.7 and saw a dramatic loss of power in the higher rpm band, with very little gain in torque in the midrange. If I had more time and wanted more top end power, I would have liked to see what a setting of .8 would do.

It also would be interesting to see if doing this same test with the 964 cams would yield the same effect. In the future, this is something I will try just to find out what it does.

When setting the cam timing it can take time to get them both perfect because the pin fits loose with some slop in the holes and slots it slides into. Once it's in there you can see it rock back and forth a little if you turn the crank shaft over one way and then the other way a little while the 19mm bolt or big nut is loose.

I wanted it perfect and exactly at 1.26mm intake valve lift TDC on each side with the dial gauge. I used the Z block and high quality German made analog dial gauge I bought new from pelican.
It takes a little time and patience because the sprocket moves a little and the pin can move in it's hole a little when you tighten the bolt. I found that when you find the right hole in the sprocket for the pin a little oil under the 19mm bolt head on the big washer and a smooth steady pull on the torque wrench with one hand while holding the sprocket from turning with the special wrench with your other hand will get it perfect and spot on after some repeated tries and then checking the valve lift with the dial gauge while turning the crank in one direction slowly over TDC a few times to make sure.

Can you give us some numbers on "dramatic"? HP vs RPM?

Interesting!
I went from stock cams at 1.2 to 993SS at 1.8 and lost 10 hp. Lost torque and power everywhere...

What are the ~expected gains from 964 cams?

Compared to SC grind cams the power band is moved up a little and there will be a little more top end horsepower when they are timed correctly.

Gents

I've a similar question re the dc20 cams on my 3.4 - they've been verified at the upper overlap mark of 2.4mm (range 2.2-2.4mm).

When the engine was was first rebuilt with dc20 cams, it's was delivering 270bhp/240 lbft - after a second rebuild, it's now delivering 240bhp/230 lbft

Could cam timing have such an affect on output? I don't know anything about cam timing, and do not know what it was set to during the first rebuild. It doesn't feel like it lost 30 odd bhp, but this is what the dyno is suggesting (same one it hit it's higher figures on)

Aside from fitting ssi's and an early dansk 2in 1out, it's the same spec/build as before

We completed the first DE with the 964 cams timed stock (1.26mm at overlap). We had a noticeable improvement over stock. The engine pulled well in 3rd, 4th, and 5th. We spent more time in 5th than we had ever done so.

I believe that it is time to get Steve Wong to create a chip for us that provides more fuel at higher end. I plan to keep the stock redline, but increase fuel delivery. We feel that the combination of the 964 cams and the 914-6 race headers require more fuel to get more gain from the cams.

We are pleased with the results so far.

John

I would think that the SSI's are preventing the peak hp.

My mistake, the last figures were taken with a set of 1 5/8" headers fitted which actually felt great on the car.

Ssi's have now been fitted to eliminate the headers from the power loss, and as you've stated, with a negative impact on top end but with what feels like an improved lower-mid range

I'll ping John an email for his thoughts on optimal overlap for a 3.4 running 10.45:1CR, ssi, single plug, but was keen to know if anyone thought a lower overlap could be prudent with my setup

Sorry for the hijack

Can't believe it's been almost 17 months since I posted this. I finally jumped in and reset my cam timing after dragging my feet and debating the value of this exercise. I had the exhaust off and the timing covers were just sitting there....exposed...daring me to remove them. So I did, two nights before Rennsport! Sometimes self-inflicted deadlines are needed to motivate me, I guess....

Once I began, the job of resetting the cam timing only took a total of about three hours excluding the exhaust removal and installation. The job was completed with the engine in place; I did not even do a partial drop. I just removed the rearmost engine tin, intake valve covers and timing case covers and went to work. Access was easy but I have no heat or AC to get in the way.

So I reset the timing from 1.8mm to 1.26mm. And I have to say that I believe it does run better. According to my butt-dyno there was no noticeable loss of low to midrange torque. In fact, it feels like the engine pulls harder and revs cleaner from mid rpm all the way to redline. Since this engine hasn't seen a dyno this is strictly my perception at work. But those of us who are so intimate with our cars know when things feel "right" or not. I do plan to put this car on a dyno at some time for air/fuel ratio numbers but I do realize actual dyno numbers are not particularly significant as they are so variable.

So, based on my experience with this particular engine build, I would recommend setting 964 cams to the stock value of 1.26 rather then 1.8. Is it a huge difference? Night and day? No. Is it noticeable? Yes. Worth doing over? In my opinion, yes.

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