When you lose a lobe does the valve stop moving completely or can you lose a lobe slowly over time on a solid flat tappet cam? Reason I'm asking is I put 300 miles on the car now and have to keep tightening up the lash every 50 miles or so and the car feels down on power, not to mention slower cars are pulling on me on the street. Is there any way short of pulling the cam to tell? All 16 valves seem to me to move about the same amount, and the carb has been wideband tuned, timing is at 32/33 locked out with vortec heads.

 

Dial indicator.

 

well since I don't have that either, guess it limits my low budget way of knowing

 

A dial indicator and a stand is about $15.

 

I am unsure of where to purchase one that cheap, this wouldn't be a home depot stocked item or a sears store would it?

 

wow n00b

 

Probably not. Harbor Freight, or eBay would be your best bet for the cheapest price.

 

what kinda oil you using?? if your not already, get that bad boy on some delo or rotella.. i've been going strong on delo oil, but rotella is basically the same thing.. just a different brand..

also, take note of the poly lock.. if the hex-headed "lock" keeps coming up, out of the nut, i would guess your cam is toast.. i had a freak lobe grind down once(actually a few times) and found one poly lock was almost out of the nut.. didnt even realize it till i bottomed out the rocker on the stud and it wouldnt tighten anymore.. on my motor, the poly lock is about a tread or 2 out..

 

It could be either the cam going flat OR bad poly locks. I had a set of ploy locks keep coming loose and we thought it was the cam, when I cut open the oil filter and didn't find ANY metal in the pan/draing plug, we tried new poly locks (same rockers) and poof ran awesome.

Poly Locks on Solid cams will sometimes wear out (constant valve lash ajustment) so its not uncommon.

What I would do first though is pull and cut open the oil filter, if there is alot of fine (size and consistency sand) metal. Don't run the motor anymore. Better to pull it apart now before u destroy the crank and pistons. (and god knows what else)

If there is no metal in the oil filter, try another set of poly locks.

And as mentioned before, makesure your running racing oil or Rotella. Flat tappet cams and most oils (even off the shelf synthetics) no longer work.

(also when using rotella, its never a bad idea to *** some lucas oil treatment).

 

wow are we playing video games online or something? Why is he a noob because he asked a place to get a tool?...wow he must be a noob what was he thinking.

 

how bout cuz that's my boy

 

Yea, i'd use mcmastercarr.com. They have a dial indicator and base set for ~$20. You'll use it enough to justify that.
Get the one that has 1" of travel, accurate to .001"
Set it up on the valve tips, zero it out (or set it to .100") when the valve is fully closed. Then rotate the engine over and record how much it lifts. If you're down less that .020" I wouldn't be too worried, that could be measurement error, imperfect cam, rockers not exactly 1.5 etc etc.
Any more then that and i'd start to sweat. Or you can try to measure on the pushrod side, directly over the pushrod itself (on the rocker). Be sure the indicator is set up to go straight up in the direction of the pushrod. (know what I mean Verne?)

Good luck! (You're gonna need it.)

 

running rotella oil 15w40, have to hit up a harbor freight later this week and see what they have to offer then.

 

Also make sure youre not pulling the rocker studs if you are running the GM press in studs. I have seen cams wear one or two lobes but never all of them. Good luck.

 

I'm running ARP screw in studs. Just checked the dipstick and there appears to be very fine sediment on there. How much "wear" would there be on the lobes? Is it noticeable while cranking the motor over that the valves wouldn't move the same amount? They appear to move the same to me, but when a stock ls1 car pulls on me on the street by a few cars and the carb is set up with a wideband, I have to wonder where all the power went.

 

If there is sediment on the dipstick, pull and cut open the oil filter ASAP. If its also in the oil filter, then the cam is toast.

It won't be visually noticable until the lifter wears though the cam's surface hardning, once that happens, it will be flat in a matter of 2 mins run time or less.

 

If theres sediment on the dipstick thats a bad sign. Like the others said, I would drain the oil and see how it looks and cut open the filter and see if you have a bunch of metal in it. Theres no way your valve lash adjustment should change that much that soon. Mine hardly changes at all, and I just check it 2-3 times a year.

 

Are they adjusted right? After I finally asked someone how to properly adjust mine, the car ran fine.

 

yes they are adjusted properly, I have set lash on cars for years now, just never seen one where they all are losing lash, but the sediment on the dipstick and the lack of power definitely point to a bad cam or lifters, which after asking around some people have had soft metal lifters do the same thing from the comp lineup. So it looks like I'll just switch to a roller setup and not worry about it again and give up a little power.

 

hope **** works out homie

 

Yea, damn comp has has some issues lately, even with some roller cams going flat. How would going to a roller give up power? would you use a smaller grind?.

I think Cammotion,Bullitcams,or Lunati is the way to go for cam's and Lunati or Isky for lifters. (Solid Roller).

Also when u rebuild it, makesure you do an INSANE about of cleaning inside the block/oilpump/heads etc etc. That fine ground down cam metal **** loves to destroy everything.

 

well the solid cam had a 106lsa which created a very tight powerband that the motor made the most power in and revved very quickly. Now I'm thinking of a 236/242 or slightly smaller roller in the extreme energy lineup, possibly the nitrous lineup for a boost combo this winter.

 

236/242 is a bit much for turbo...i wouldnt go much more than 230/230 especially since you're doing twins on a streetable setup. alot of people have made gobs of power on as little as 218/218 cams. i believe single pattern is the way to go for boost, and on at least 112 lsa ut 114 would be better. ...but you already knew all that.

 

single pattern over the split duration nitrous type cams? Guess I'll have some more research into this, but I was always under the impression that extra duration on the exhaust was a good thing for FI

 

um...call the cam company and ASK them for which off the shelf cam they recommend. Call all of them, and youll be surprised how close the specs for the cams they recommend are. I already told you to get a custom grind but you don't want to so atleast ask them which off the shelf grind would work best for you.

 

A Custom gind is needed to make real power for any custom turbo setup. Everything off the shelf will be leaving alot on the table.

Only the mustang guys with 302's and bolton turbo kits see the full potential off of the shelf cams.

Not to mention its the same price off the shelf VS custom so. Might as well have one that matches.

 

i already told him it costs the same, can't put a price on ignorance

 

sears tool dept. should have them. maybe alittle pricey paying for the craftsman name on a tool made in china.

 

i had a buddy that had prolly 5-6 lifters/ cam lobes go bad on his cam, he had about 500 miels before he pulled the cam and found out, he was having the same probs as u and just decided to pull the cam and put in a hyd. cam. when he pullled it he had found the soup cup lifters and worn lobes, some of the lobes were prolly worn down 1/2 way but we didnt notice it when we just looked at the valves, when we took the oil pan off there was prolly 1/2-1" of metal/oil paste in the bottom, it was a messy jjob

 

cam will be out this week and i stopped driving the car, got a roller cam to go in instead, might be replacing bearings and such as well, we'll see how it looks.

 

what specs did you decide to go with on it? is it for boost?

 

no idea on specs until i get it from the cam grinder, i'll have to ask his permission if i can even post since it's a custom ground cam. Yes it's for boost setup for my motor specs, he had probably 30 questions to ask me before he got off the phone with me.

 

So then are you willing to divulge the specs on your now toast cam? Or is that still a hush hush?

 

vortec setup up also. I was doing an intake & rocker swap when I noticed I was having problems with my cam. I had been down on power lately and the car would run rich. I pulled a couple of lifters, and one would not come all the way out of the block! When the cam wore down it mushroomed the lifter!

I just flushed my block with some cheap oil. I would take a ride or two and change the oil. Did it about three times. It never did come out too dirty.

 

Why such a thick oil?

Adjusting every 50 miles or so is wayyyy to often. I bet it takes just as long for a cam to wear out, as it does for an engine to wear down, or get "tired".

Is your oil pressure good?

Please take pix when u are disassembling, its valuable info. Hope the new build goes smooth,.

 

custom cam, can't divulge lobe profiles, you want one I can get you one for $375/400-ish.


oil pressure is fine i'm running that oil because it has the zinc, etc that solid cams require which synthetic oils have removed due to stricter emission standards. 15W40 isn't really much thicker than 10w30 anyways and the bearing clearances were right in line for that oil. Solid cams do not have a shelf life of a typical hydraulic or roller cam.



and talk about bringing a post back from the dead from july.....

 

Actually, even Rotella is losing most of its zinc content now, from what I hear. The best route now is either a racing oil "off road use only" sorta stuff, but it only really comes in 20/50 weights, or add some cam break in lube to your oil, like the stuff Comp or Crane sends with their cams. Its loaded with the good stuff.

 

I wasnt aware that the lack of zinc was an issue. I havent owned the same engine long enough to know, but between my freind and i, we run high mileage full synthetic mobil 1. Hes been running it in the same olds 350 for about 4 years now, and its in good shape for such an old engine thats pushed so hard.'


Youre right, 15w40 isnt much thicker than 10w30, but it makes the difference on start up. The quicker you can lube the engine at its peak wear moment, the better it is.

I think we can all agree though, 300 miles is premature wear for a cam the way youre describing. Curious to find out what happened, cuz im stumped.

 

I know it's probably a bad batch of lifters that comp was known for probably 2 years ago or the hardness on the cam suffered, I'll find out later this week when I tear into it.