I just got my hotcam from SDPC. It came in a sealed tube. I opened it up to check out the cam and found there is no cam card. I have always degreed in my cams when I installed them in the past. Any ideas on where to put the #1 intake CL on this one?

 

check online at their site

 

That is good that you are degeeing the cam. Get ahold of them and request a card or as mentioned see if they have them online. Hate to see people putting cams in without degreeing them....never truely know if its put in right without first doing this.

Good luck!

 

Thanks guys. I have searched their website and all I am seeing is 112 degrees between lobes. Not seeing where number 1 intake goes. I am going to search some other forums or call them tomorrow if I can't find the info. I can't believe anyone ships cams without cam cards these days.

 

Using the LSA method, if it ground on 112s, then 108 will put it in 4 degrees advanced. If you want to use the degree at .050 method, then you'll need the card for that figure.

As to whether or not the numbers on the cam card are actually the "best" setting is anybody's guess. Just remember though, any card settings are only "suggestions/recommendations. The "absolute best" setting for your particular combo would require back to back dyno testing of different settings which, for most of us, would be a real PIA.

Here's an example: Dyno testing results printed in one of the mags showed that the TPIS ZZ9 made best all around torque and HP installed 1.5 degrees RETARDED. I'm still trying to figure out how they go that 1/2 degree.

Jake

 

how is installing it straight up not installing correctly and how would you know that the cam isn't installed correctly and what difference would it make if you can't adjust the timinmg of the cam????

 

By not degeeing the cam, you are assuming that the dowl on the cam is perfectly located, as are the keyway/mark on the crank/cam gears, and not to mention the guy that setup the cam when grinding it was on top of his game and it wasn't monday morning or friday afternoon at closing time with his hot GF standing in the doorway giving him a dirty look for not being ready to leave for their date.

When you degree the cam you are checking to make sure the opening and closing events of the valves are consistant with the cam card that the cam was *suppose* to be ground to.

I have seen them off 2-4*. Also lots of times you don't know if the cam already has the 4* advance that you want to give most cams already ground into it. And the cam cards for most race type cams do not specify, and I don't trust talking to some desk jockey that isn't even familiar with the cam you bought.

The only way to know for sure it to check it. I asked these questions on the bullet racing cam I installed in my 434 last year and the guy told me it would have the advance ground into it. So I started with the install and checking of the cam at straight up. Sure enough i would have bet a case of beer that it had no advance ground into it. So I had to take it back apart and install it with the timing gears turned to 4* advanced. This time the events occured exactly at the degrees the cam card said it would.

But had I not checked it and trusted the guy, my car probably would have been a stone.

You asked how you can change it if its wrong. Two fairly easy ways, the first being easier. This is with a timing setup that allows aligning of the gears to the keyway on the crank at 3 different positions. sometimes even more if you get a real high end timing set. Most come standard with +4, 0, -4.

Now if you fall inbetween say at 2*, depending how far off it is and where you wanted it to be at, you can buy inserts that are offset for the cam gear. These typically require some machining to the gearset for them to be inserted in, and then you can dial it right in. Usually they are off in intervals of 4* though (advance ground into them or not).

I am usually pretty satisfied if they are within 1/2* of where I wanted them to be at.

All depends on how fussy you want to be. And it can make a HUGE difference in the power you generate.

 

Those are the reasons I have always degreed my cams. I have had some that weren't right and some that were dead on. Installing this cam is a lot of work and I have to know that it is installed where it is supposed to be. I do agree that putting the cam where the card says will not always produce the most power but that is where I want to baseline from. I have experienced different cam postitions make 5-6 tenths difference in the 1/8th mile. Bottom line is, with my experience, this is too much time and money to put into this project and to seal it up blind. I need to know the details.

Thanks for explaining it Jesse. I will be contacting you for a chip after I get some baseline runs on it. Can you tell me, besides the main dyno sheet, what other info would help you with my chip?

Greg

 

Hey guys, I had some help finding the cam card on line. Here is the link to the cam card in case someone on this forum needs the info.

LT4 Hotcam Card

 

Jake,
Can you remember which magazine ran that article? I would like like to have a read. I'm sure I probably have it somewhere, but must have missed it.
TIA Dave

 

Good points made. The zz9, w/a cloyes double roller (no hex adjust) using standard markers on the sprockets, mine came out to 109*-110* (TPIS recommends it at 108*, and I used the comp cams method). I think the BEST place to make max power, is to degree a cam is at max compression. As jake stated those are starting places/suggestions that work w/out a dyno and or other serious considerations. JMO

 

Unfortunately I can recall the specific mag. I do recall it was one of the "biggies" though, like VETTE, Corvette Fever, Hot Rod, Super Chevy etc.

Along those same lines, the author of the article wrote that although there are many other cams offered that have virtually the same specs as the ZZ9, when tested on the dyno, the engine always made more power with the ZZ9.

Also, even though the ZZ9 cam card had the specs listed on it, when I had the ZZ9 computer checked at a machine shop, the numbers were significantly different than the card specs.

I've got the actual "checked" numbers saved on my home computer. From memory, it was the intake closing point that was off the most, and, as you probably know, of the four events, the intake closing point has the greatest effect on power production.

I'd track it down for you but right now I'm in Chicago and won't be back in Texas for a couple of weeks. Email me around that time and I'll go through my collection to find the article. Chances are I'll forget without the reminder; LOL.

Jake

 

Are there errors it the Hot Cam cam card? Both lobes have .328 lift,with 1.5 rockers valve lift is .492. With 1.6 rockers lift is .535 in and .525 exhaust. Seems to me they should both be .525. Additionally both durations are given in cam lift. I thought .050 was valve lift.
Maybe I am being overly picky with all this.

 

Jake,
I know this is deviating from the original thread a little and I apologise for that, but I would be interested in your measured zz9 specs you have, in relation to the cam card.
I have had a zz9 cam for a while now and will be fitting it when I put my engine back together and I also found the cam card differed from tpis's std. published specs a little. In fact they didn't add up to me. I queried this with them and they just said all cams were ground a little different, which at first made me doubt the quality of it. The overriding point was to install it at their recommended position using the 50 down method rather than seat timing methods due to the non-symmetrical lobe profiles.
I think they are reluctant to give the 'correct' specs away to avoid copying although this is JMO. I have never heard a bad report about a zz9 only reports that it wasn't hot enough for some. Were the actual specs bigger than published or smaller? I say this, because they told me to shoot for 10.6-10.8:1 CR and not to go below 10.5:1 compression ratio for best results, which I thought was quite high for pump gas and the cams specs.
Dave

 

I had Dennis Wells' Racing check my ZZ9 on his computerized camshaft checker and he gave me a printout of the results. I had him check ONLY the #1 intake and #1 exhaust, not all 16 lobes. After he gave me the print-out I copied all the numbers over to a *.doc file on my home PC, but I don't have access it that file now.

I had it checked several years ago, but I believe the checking cost was only $25.

I'm going from memory on this, but as I recall, the .050 duration was in the area of 209, (something like 208.5) which is shorter than the advertised ,050 duration. I recall, also, that the lobe lift was a little less than advertised.

A couple of years ago, this topic came up regarding the ZZ9 and I posted the specs I received on the print-out. I don't know if that post is still available, but you can check to see. In any event, I'll email it to you after I return home when you touch base with me.

Jake

 

All properly selected cams will make the best combination of maximum power and torque when installed 2 degrees advanced. This would mean timing the intake lobe center line 2 degrees less than the lobe separation angle at TDC. If you would like to enhance low end torque at a slight penalty of high speed power (recommended for street engines) then advance the cam 2 more degrees or 4 less than the lobe separation angle. 6 degrees advanced will make yet a little more torque but the power losses are greater than the torque gain now and the net result would be less area under the curves. If you installed the cam straight up (intake center line at 112 in your case) the engine will make maximum horsepower but at a small cost in low speed torque. Installing the intake center line 2 degrees retarded will yield less power and substantially less torque and result in an extremely lazy engine. If you have to install the cam at a setting much different than 108-110 for a 112 cam to get the engine to run better then you have the wrong cam for your engine (or more specifically your heads, intake, exhaust system, etc., and operating range) or a mistake in finding TDC. This might be a good time to mention finding exact TDC and having a good large diameter degree wheel properly mounted with a good pointer and dial indicators that won't slip is very important. The intake centerline method is probably the best way to check and is as accurate as anything. I wouldn't recommend the .050 method due to tolerance error unless you are experienced with this. Install the intake center at 108 to 110 and you absolutely cannot miss. It might also be interesting to note that the engine will run better with an increase in rocker ratio. A good rule to remember if you want horsepower: the better the heads are the more cam (and rocker ratio) the engine will take and the higher the operating range will be. You cannot use a cam as a crutch for poor heads. If the heads are puny stay with a small cam to at least have some torque and low speed power. Installing a big cam in an attempt to get them to run will only make it run worse everywhere. Be sure you have enough piston to valve clearance if total lift is increased much over stock and check to make sure you have suitable valve springs with some room before coil bind. Check exhaust valve clearance at 10 degrees before TDC and intake at 10 after. You need a minimum of .050 on the intake and .100 on the exhaust. If close to this check them all to find the closest one. They will vary a little due to production tolerances; rocker ratios will vary a little for example. Don't worry about checking cranking cam compression because it doesn't mean anything after the engine starts. In a running engine you are only concerned about achieving high BMEP which results from the sum of mechanical compression, the intake and exhaust tracts ability to move air and inertia ram characteristics and accoustic resonance. Your friendly neighborhood head shop can help with these.

Have fun,
Greg