Just broke in a new Comp. xs268 cam. Went something like this;
1- Started right up first turn-died after 5 seconds.
2- Started right up again-died after 10 seconds.(No Choke and wasn't giving it enough gas)
3. Started up-ran good-did the normal routine 1,500-2,500 varying rpms. After 5 minutes it was overheating at 230 or so-shut it off.
4. Fixed overheating problem. Started her up and ran her for 15 minutes before it overheated again
5. Pushed car outside(too hot in garage) and started her up for another 10 minutes and shut her down.

Now the problems; I didn't really notice it in the light of the garage but when we pushed it outside in the dark you could notice that the header tubes for #6 and #8 were glowing slightly(not like red hot). After pushing it outside it also started to devlop a clack-clack-clack in the areas of #6 and #8 clyinder...not terribly loud but noticable. I didn't have time to dial Carb in or change idle but at the end of break-in we let it idle where it was. Idled at 1000rpms, was a little rough, and the vaccum guage bounced about 1 mark between 12-13.

I'm gonna open it up tommorrow(have to change valve springs anyways-was using softer ones to break cam in) but what should I look for and how to see if I wiped a lobe? All comments are appreciated!

Maybe, the usually sign is back firing through the carb when you rev it up a little. If you tighten the lifter a little and it quiets for a second then starts ticking again that is usually trouble. Also remeber Comps XE line is noiser then most cams due to the super agressive ramps. The XE256 that I just installed has a slight tick that refuses to go away.

Steve

You should be fine. I had to shut it down afterabout 2 minutes due to noise. #1 valves had like over .100 lash! ( had to pull those two lifters to fish out a washer than had fallen in the galley- guess I brain farted on lashingthem).) Few pipes got red hot and messed the ceramic coating. Motor now has nearly 5000 miles, it runs mint! You'll be fine. I was so paranoid I ran around with the outer springs only for maybe 2.5 hrs of runtime.

I don't how the Lunati I run compares in intensity ( you can see the difference between it and the old Crane, the valves ZING open and then close gently) with the XS line, but it took maybe 6-7 lash settings before it 'took a set' as 69LS1 says. And everytime I had doubts, lifter going, lobe going, pushrod mushrooming, etc...so don't fret if you have to lash that sucker multiple times before it holds.

What did you end up with for rocker nuts? CoolNuts from Crane? Back in the old days when we stormed around Webster as kids, all running solids, we double-nutted them. DOn't know if that's advised but it works. Guy named Bob Lambaizzi always had the baddest stuff, including a tubbed t-rammed 454 75 Camaro. This was in '77-80. He blew my Nova away with his 69 LT1 Vette.

But I digress, ah the halcyon days of my high school youth in Webster.....stopped by the cops EVERYTIME they saw me in summer of '77. Wonder if Sgt. Flood is still on the Webster PD? He won't remember me, but the 75 Nova he chased down one night after street racing. redface.gif Not my shining hour.

Originally posted by 427L88:
What did you end up with for rocker nuts? CoolNuts from Crane? Back in the old days when we stormed around Webster as kids, all running solids, we double-nutted them. DOn't know if that's advised but it works. Guy named Bob Lambaizzi always had the baddest stuff, including a tubbed t-rammed 454 75 Camaro. This was in '77-80. He blew my Nova away with his 69 LT1 Vette.

But I digress, ah the halcyon days of my high school youth in Webster.....stopped by the cops EVERYTIME they saw me in summer of '77. Wonder if Sgt. Flood is still on the Webster PD? He won't remember me, but the 75 Nova he chased down one night after street racing. redface.gif Not my shining hour. I have poly-locks of unknown origin from previous owner-they were fine. I think I owe a huge dept of gratitude to the Webster Police. I was pulled over by a Sargent in my Camaro when I was 16 taking a ride around the block with no insurance, only a learner's permit, no registration, nothing, and he let me off with a warning. Also got pulled over for no headlights and I was driving after 9PM when I was 19...I told him right off the bat and he let me go. Nice guys, nothing but good things to say. Now, Irondequoit cops on the other hand, man I use to live there and they aren't very nice, but I suppose they have to be seeing as crime is getting bad in that neighboorhood.

Well heres the UPDATE:Well I tore it apart and put a dial indicator on ever single pushrod(have to take off rockers anyways to change valve springs to the correct ones-I was using the stock 25K+ hydraulic springs in my world s/r to break in the cam). Put a dial indicator on every single pushrod. Some of the clyinders it was hard to get to and its hard to eyeball the dail indicator to get lined up correctly(and its a Summit dial indicator so its prolly not 100% accurate) with the pushrod but all the lift numbers cam within .008 of the cam lobe lift specs.

Is that withint the accaptable tolerance level? I've seen pics of wiped cam lobes and you can notice them with your eye, unless your vision is incredibly I don't think you'll notice .008. So should I just change springs, set the valves using ICEO method(I used the 90 degree method to 'rough' them in) set up the idle screws and everything and then go take her for a ride and see how she is?

i had a 57 chevy with a 350 and the headers glowed bright orange when i started the engine up for the first time. i finally figured out it was getting way too much fuel pressure and the needle would never sit on it's seat. check your oil and see if it smeels like gas ! graemlins/clonk.gif

Originally posted by AllGoNoShow:
Now the problems; I didn't really notice it in the light of the garage but when we pushed it outside in the dark you could notice that the header tubes for #6 and #8 were glowing slightly(not like red hot).Sometimes timing can cause the headers to glow. You may need to check and adjust it.

The headers glowing slightly are usually not an issue.
I see it all the time on the dyno when breaking in engines around 2000-3000 with no load.
As soon as you load the engine the glowing usually goes away.

Change the springs, readjust the valves at TDC & then recheck at EO/IC just so you know you got it right, check your timing & go drive it.
Then recheck your lash I see if it changes much.

What heads do you have, Iron or aluminum?
If aluminum adjust the valves .004 tight cold.

Originally posted by Wolfplace:
What heads do you have, Iron or aluminum?
If aluminum adjust the valves .004 tight cold. I have iron heads, I've heard adjust .002 over reccomended lash and they will tighten up...true?

Originally posted by Wolfplace:
The headers glowing slightly are usually not an issue.
I see it all the time on the dyno when breaking in engines around 2000-3000 with no load.
As soon as you load the engine the glowing usually goes away.

Change the springs, readjust the valves at TDC & then recheck at EO/IC just so you know you got it right, check your timing & go drive it.
Then recheck your lash I see if it changes much.

What heads do you have, Iron or aluminum?
If aluminum adjust the valves .004 tight cold. Educate me Wolfman, why does a load make the headers stop glowing??

Because with no load you ain't even on the main yet & you are confusing the carb.
You have enough air going into the engine to run at 2000 or so but not enough air going through the booster to get a decent signal
As soon as you load the engine you have to open the butterflies further & will start pulling fuel from the boosters instead of mostly off the idle & transition slots.
If you put even more load on it you will open the power valve & richen it even more.

Havent monkeyed with iron heads in a long while, yes, they'll shrink 1-2 thou when warmed up.

Boy, things havent changed much, Irondequoit cops had that rep 25 years ago. Although they pulled me over EVERYTIME they saw the car after ' the incident', the Webster PD were always very cordial, as, of course, was I.

You're good to go, and like I said, don't freak out if ya few open up on you in the first 500 miles.

I had a real bad "clack" at idle after doing my break in. I re-adjusted the rockers twice and still no luck. Turned out I used crappy header gaskets and it was an exhuast leak making that noise. If you rev the engine up and the noise goes away I would replace the header gaskets with the extra thick ones, worked for me! Good Luck.

Originally posted by AllGoNoShow:
</font><blockquote>quote:</font><hr />Originally posted by Wolfplace:
What heads do you have, Iron or aluminum?
If aluminum adjust the valves .004 tight cold. I have iron heads, I've heard adjust .002 over reccomended lash and they will tighten up...true? </font>[/QUOTE]=
I adjust the iron stuff on spec cold but I also recheck them after breakin & readjust as necessary.
I normally check all of them hot after breakin & recheck cold so I can adjust cold which is usually going to be easier,, at least for me.
It is a real good idea to know what the lash is both hot & cold so you have the option of either way regardless of circumstances ;)

Well I put the new springs in and toke it for a drive after re-setting timing(turns out it was very retarded during break-in). I doubt its wiped....runs great, lot more power then before. Actually got a little smoother throttle response too!

Seems like it is running a little hotter tho with the .5 compression increase and the bigger cam...might have to finally wire in the high speed of the electric fan I have.

Pull the valve covers and watch it idle.The pushrods should be spinning like tops. If so, you're ok.