How do I go about finding the cam specs on a cam I got at a swap meet. It has no markings on it.
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How do I go about finding the cam specs on a cam I got at a swap meet. It has no markings on it.
It's junk. Use it for a doorstop. I could explain how to determine what it is, but it would cost you more in tooling to do it than it would to buy a new cam.
I second that statement, Although they can make fine lamps also.Quote:
Originally Posted by techinspector1
I third that.Quote:
Originally Posted by techinspector1
I also second that.Quote:
Originally Posted by mooneye777
Kitz
Well I guess we all come from different worlds. I am poor and have to use cheap,used parts to be able to hot rod, unlike you guys, obviously. I hoped I could find useful tips on this site, but it seems it's no different than any ricer forum out there! But for anyone that is actually interested in helping someone out, would I be able to use a lifter checking tool, placed in the lifter's place, and with a dial indicator, and degree wheel, find lobe lift,duration,etc.? Help from anyone that knows more than just " throw it away and spend some money that you don't have" would be greatly appreciated. Thanks, Dave.
I am totally offended, Ive never seen or talked about rice on this forum. I am not sure what you payed for your cam, but summit sells brand new ones for 52 dollars. You are plain taking a chance running a cam you know nothing about, you could find the valve lift by what you are wanting to try. But the duration will be a mystery. And if the cam you bought is used, is it still any good, gauged, scored, worn anywhere. Chances are you will install it and within a couple weeks or sooner it will destroy itself. Unless you bought the cam and exact lifters it was ran on, and every lifter was marked exactly to what lobe they were ran on, if not you will be buying another one anyway. Now think that if the cam is a stock cam just like or worse then the one you are replacing, thats more wasted money. I am sorry for your financial sittuation, but running used or mystery internal parts is a very risky business practice. And if my car had to sit for another month to get a new part that is the exact one I want, I am waiting, I know because ive been there before and will be there again, no rich daddy warbucks here,
If you can, place the cam in the engine. Take a solid lifter and install a dial indicator so it is touching the top of the lifter and zero the scale. Wit a degree wheel and pointer turn the cam slowly until you reach .050 lift. Record the number on the degree wheel. Continue turning until the dial indicator reaches the highest reading and record this number. Now tiurn the cam until the dial indicator comes down to .050 lift and record the reading on the degree wheel.
The degree wheel total between the two numbers will give you the duration at .050. Multiply the maximum lift number (off the dial indicator) by your rocker arm ratio to get maximum lift.
Do this for both the intake and the exhaust lobes.
To get lobe seperation angle will be a little more difficult, but basically, measure degrees of rotation between intake max valve lift and exhaust max valve lift.
Good luck.:3dSMILE:
Thank you very much! I have the cam in the engine, and have removed all but no. 1 piston to reduce friction. I thought that would be the way to check it but wanted to ask someone with more experience. I can't see junking a cam with hardly any wear, which could be a good performer, simply cause I don't know it's specs. thanks again!Quote:
Originally Posted by Geezer2
While I sympathize with your need for economy, I have to agree with the guys telling you to junk it. By the time you put new lifters, gaskets, and a lot of time and effort into it, the $60-$100 you save will look like peanuts. Especially if it wipes out in a week like every used cam I ever tried to re-use did. Then when you do buy a new one there's all the worry about what those grindings did to the rest of your engine. It just ain't worth it, man.
Hey Superdave:
I'm fairly new here as well and I have to say that this site has the finest technical minds you'll find anywhere. Most of them have years (some over 50 years ) of practical hot rodding and that includes a lot of engine building.
There used to be a device available called the "Cam Doctor". It was a precision measuring device coupled to a PC that indexed and reported on all aspects of a camshaft, i.e., lift, duration, lobe separation, shape, slope, etc, etc, etc. This machine is no longer made but a used one goes for $2500.
Please know that many of the guys on this site have used similar devices and are experts in the engine building field. They possess the knowledge and have paid the dues to allow them to say things like "get a new cam from Summit". We're not being jerks - however, we will respond in kind - which typically means your posts will just go unanswered.
Don't throw away an opportunity to learn from hundreds of years of combined knowledge and enjoy the collective wit and wisdom represented here.
Regards,
Glenn
Well said Glenn
And if you're bound and determined to use it, make sure you check all the lobes for wear using a dial indicator. Is it for a mechanical or hydraulic lifter???? Knowing the lift and calculating the duration and ensuring should help you make a half ways well informed guess as to whether it will require solid or hydraulic lifters..... If you install the wrong lifters, almost guaranteed self-destruction of the cam and the new lifters.
But hey, what would a bunch of millionaires know about it, right???? IMO, buying a used cam with no lifters and not knowing if it's even usable for your application is hardly a good way to save money......
btw, you sure do know how to make an entrance....
I'd try Geezer's method, but then.............you already know my opinion on the subject!
buy a new cam or cam kit there are good deals out there on them competition products has great deals on cams and threre is some on the broom sheet and pbm has some kits to. i buy from both it not worth the trouble in the long run like many have said . yes a cam doctor would be nice to have
Several years ago a machinist I knew (actually worked for NAPA) had one of the Cam Doctors. It was pretty awesome, but a bit fussy as well and it took a good bit of time to get setup and he always measured each cam twice. Well, at his rate ($50 per hour then - would be more today) one did not have to be a rocket scientist to realize that it was almost always cheaper to just get a new one. He had a fondness for the Isky roller cams and could put a sweet deal together for not much more than fussing with a "used" cam.
I've built a lot of SBC and installed cams/lifters from GM (hydraulic Z28 type. Still $200+/- w/lifters if you can get the parts guys to be creative!) as well as cams and lifter kits from Crane, Lunati and the Iskys too. while I have not used one, I see Summit has a camshaft kit w/lifters for under $100!
They all make some good units if one remembers to keep the entire build in mind so as not to end up with a sloppy beast that belches raw gas and runs like a three legged pig. When the need for that high RPM jolt is there by all means go big, but for most streeters I still like to have a smooth idle and good performance from idle to about 5500. Just my two cents..
Regards All,
Glenn
Well it seems most everyone has it in for me now, however, how can I tell if I need to use a hyd or solid lifter? Sorry if I came off as a jerk, just kinda hit me the wrong way I guess. F.Y.I. I got the cam and a new set of lifters for 25 bucks, and all I was told was it had .510 lift, that's the only reason I got it. I understand it's risky, but if it don't pan out, i havn't lost much. Sorry again for being rude, I really do appreciate experienced advice.
Sure do! Cause you're gonna help me figure this out this weekend!Quote:
Originally Posted by Sinister
Isn't there any kind of number stamped into one end of the cam, like 280H or something??
how about paint colors gm use to paint them by the gear ??i do not know what color is what but someone may know?????
If the lifters were with the cam, and you're sure they are the right ones, you might get away with using it. I would still recommend buying a new cam to go with the new lifters, but it's your nickel.
Superdave asked a question, he did not ask for an opinion.
I tried to answer his question in a simple and direct manner.
I didn't express my opinion on the feasability of what he was doing because that's not what he asked!!
I know yjere are a lot of very knowledgeable people on this board, that's why stop by. BUT, sometimes just answering the question asked may be the way to go.
By the way, I'm NOT trying to start trouble or get anybody riled up, just giving my opinion (which nobody asked for).:rolleyes:
I don't think anyone was hatin' on you.Quote:
Originally Posted by SSsuperdave
Lacking any ID markings at all this question cannot be answered exactly so opinions will be the general response. Even if you had the markings you do not know the history of use etc so you are taking on risk at the very least in going forward with it. Period. Seems to me that you do not have enough vested in it now to warrant going forward with it anyway given the cost and availability of new ones.
Even if you ain't a millionaire. **)
Kitz
Cams are like sex partners....if you dont know where it's been, you shouldnt be screwing with it!!
I agree with most of the comments and if I end up putting the cam in my motor, I will be honest on reporting how long it lives. However, I still don't know how to tell if it's a solid or hyd cam.
Thank You! Right or wrong, I'm just trying to learn more.Quote:
Originally Posted by Geezer2
PLease read the captions and look at the picture as it describes in generic form the differences by looking at the cam. note there is type above and below picture. The type below the picture is most impotant, I hope this helps you out some.
1, After break in, a flat tappet cam is married to its lifters. You cannot move lifters between different bores, and you cannot use those lifters on a different cam. The lifters either stay with that lobe, or get thrown out, period.
2, The following picture shows a flat tappet camshaft in the front, and a roller camshaft in the rear.
You cannot visibly tell if it is a solid lifter cam or a hydraulic lifter cam. The rate of lift (not the lift) is one factor in the solid/hydraulic design. Measuring such and then analyzing the data is not something you can do...plus you have no "specification" for this cam to compare your data with. That's the problem with unknown equipment. For all you know, it's a stock 2bbl cam that someone removed in order to install a high performance cam. The visible difference between cams is so small, it is a game of chance.
Look closely again at the nose of the cam where the timing gear mounts....like several others have said, there should be a couple of digits stamped there. For all you know, you have a 307 2bbl powerglide cam.
For the expense of tearing an engine down to change parts, it appears risky to use an unknown part. If the lift is too high, you risk coil binding the springs. Perhaps some of the guys here know if you can run hydraulic lifters on a solid cam....you cant do the opposite.
Here are a few old notes that I dug up re; color codes on GM camshafts – not all mine, some from Car Craft and Chevy High Performance. I do know that the original colors turn after use due to heat and exposure to oil. Surprisingly enough a small dab of acetone on a Q-tip brings back the original color.
The late 60’s Chevy cams were identified with painted stripes on the cam gear end of the cam. Chevrolet 3927140 camshaft had a white stripe (usually turns to beige after use). This was the solid lifter cam used in the 302 Z28 motor. They’re rarer than hen’s teeth so I doubt there are a lot of them at swap meets.
I have an L-79 cam in a small block that had green, orange and white stripes (also discolor after use). This is a really good hydraulic lifter cam with 222 degrees intake/exhaust and .447 lift with 114 degrees separation. A bit of lope at idle, but a string performer through 5500RPM and IMHO, a good cam for a mild mannered SB that still chips tires good and loud when shifting.
GM part number 3736097 used in early 60’s had one green stripe (probably brown with age) on the distributer gear end. Mechanical lifter with .381/380 I/E lift that works well with 1.6 roller tip rockers.
The renowned “Duntov 30/30” camshaft from the FI 327 had a pink or white stripe, pink stripe turns red/brown and white turns off-white with age.
I have several cams that have the part number stamped on the backside of one of the bearing surfaces.
Regards All,
Glenn
It is a flat tappet cam. On the transmission end it is stamped 268. I understand that the lifters wear together and can't be interchanged, however would not new lifters, a "blank slate" if you will, eliminate this problem? Also, I ask because I don't know, it seems that you could run solids on any cam cause ramp rates aren't a factor like hydralics.
Most of us who have raced have had to reuse parts out of necessity. When you are strapped for cash but are still in the points hunt you are forced or tempted to do things you shouldn't. That being said I have run used cams a time or two with some results for a short until I could afford to change it out. The problem I think you might be facing is that (I assume) this is going into a street motor for which you hope will be a long time. Chances are better than 50% it won't work for you. But it is something dictated by your current circumstances.
I dont know why you could'nt, but I am almost sure you are not supposed to. It could be maybe because the short duration on a hydraulic cam is too steep of a climb and rapid step down for a solid lifter. The hydraulic spring might compensate for this quick action. I am only speculating now though, just letting my common sence work a bit, and sometimes thats a stretch. That is a good question I think. I am thinking with my solid roller for example, lash is set at .018 and .022, thats not much play for the quick and rapid lobe to lifter movement required especialy at 7000 RPM. remember just talking out my azz at this point.
You may have a Comp Cams XE268H. Follow this link and then call/email these guys for some more help in identification.
http://www.compcams.com/Cam_Specs/Ca...x?csid=93&sb=2
While I have never used this cam, specifications look pretty good for a TPI small block.
A solid lifter cam has a take-up ramp that slowly eases the lifter up until the clearance is gone. If you put hydraulic lifters on one, the valve starts opening way too soon, and since it only opens the amount that the clearance is supposed to be, the valves will burn out prematurely and the engine will run poorly at idle due to the too-long duration.
FWIW, you can run solid lifters with a hydraulic cam but not the other way around. If you do run solid lifters with a hydraulic cam, you set the tappets at .003-.004. I know, because back in the 1960's I did it on the 283 I built for my '59 Impala. This was on the advice of the machinist that worked with me on the engine. I never had any problems with it.
So would it be safe to say that solid lifters would be the best to run if I can't find out whether it's a hyd or solid? Seems to me that a solid would follow the profile regardless of what it is whereas a hydrolic could possibly collapse because a solid profile may be too steep for the hydrolic valving action of the lifter.? I did check it with a degree wheel and dial indicator and it comes out to 230/230@480/480 w108 ICL. I know it's an Erson brand and I found a cam with the same specs on their website.! Also, my dad had a brand new, still in the box Comp cam, with card and all, and I put it in and checked the same way I'd been checking the other and it came out to exactaly what the card showed! I feel confident with my measurements, since I have a known cam to compare against now. A larger degree wheel would be nice too, since the 11" one I'm using now is kinda, eh, but it works. Anyone know what a cam like this would be good for? Still curious about the lifters though. Thanks for all the replys!
If you know it is an Erson cam, call them and give them your specs. Chances are they can tell you whether if it is for hydraulic or solid lifters. And make sure your valve springs are matched to the cam. The wrong springs can cause cam failure or valve float. If in doubt, buy new ones from Erson. Good luck.
Just to really get ya'll riled up, the junkyard motor I'm using this cam is a factory roller block! What a waste, huh?
That statement might stir up a hornets nest!:LOL:Quote:
Originally Posted by SSsuperdave
You should be tied to a pole and caned.:eek: :3dSMILE:Quote:
Originally Posted by SSsuperdave
Put the cam back in the block and check the intake closing point at zero lift and 0.050" tappet lift. That will tell you what static compression ratio you need to use in the motor to get the proper dynamic compression ratio in order to have a motor or not have a motor.