How to tell if I've got a bad cam?

[TexasRed]

Is there a way to tell if I've got a bad cam? It's a pain to pull the valve covers but I may have to. I had some weird issue with a vacuum reading from the manifold being steady but through the PCV port in the carb it would sit there and kinda fluctuate between 17" and 19". These are at idle. Oddly enough it was almost like it would surge to 19" and then drop back down to 17" for a while and then do it again. I changed to a 700r4 from a th350c and got like crap gas mileage. The TH350C gave out on my on the freeway and I may have overreved the engine trying to get off. Would that cause a loss of vacuum and cause fuel economy to go into the dumpster? My 305 (yes 305) had somewhat a lumpy cam but it always seemed to have a good idle (not quite smooth but almost) so maybe that puts the power band too far above the cruising RPM the 700r4 provides but I doubt it. Thoughts?

[VileZambonie]

Tune it up and set the timing. Make sure no vacuum leaks and recheck it. If you wiped out a cam lobe it would pop and backfire.

[TexasRed]

Well, I (tried) rebuilding the edelbrock carb I had on there for around 4 years and it might not have gone so well. I don't think that was the problem though. I'm getting a q-jet built for me but that guy is taking a little while (it may be racer season). I've got a real bad flat spot when I just barely put my foot on the gas to EASE into acceleration. New plugs, wires, distributor (Non -ESC). I had some bosch platinums in there for a short time and a couple were fouled. Not sure if that's a sign of something? The timing I set by advancing it until I get valve clatter from acceleration and then retard a degree or two. I need to get a tach on the beast but I'm lazy. I need to build the 355 but I may not have enough time before I kinda need it.

Oh I forgot to add: Thanks for your help and any other suggestions you can offer. I'm going to start soaking Holley parts, maybe I'll get that built.

[choptop]

Really sounds like a carb problem. I had similar trouble on a 468 in the wifes truck.Replaced the carb, and it went away. The stuble off idle I believe is an accelerator pump malfunction.

[1976Scottsdale]

I would be thinking carb issue as well.  If you want to be sure, then pull the valve covers and chevck ur rockers.  Someone on here had a valve lash adjustment article that works really well.  It will take some time to do, but when ur done you can look at your rocker nuts and see a bad lobe by an oddly high amount of thread showing above the nut.  But first fire it up and see if you have a rocker that aint moving if ya do then thats the issue.

[TexasRed]

Well, I'm going to try the carb issue first. The guy building me one should have it done by the end of the coming week and I got most of my 4175 down being urethaned for protection against corrosion. I need to hook up a tach, do I just hook up the tach wire to the tach side. I see Jeg's offers the proper connector but can I use a regular female spade connector? 

Has anyone used the AED or Quickfuel rebuild kits for Holley carbs? I plan on using the AED but I may use the Quickfuel.

I've pulled the edelbrock off the engine and put it in a DHL box to send it to VileZambonie since he offered to look through it and see if there's a problem (just kidding he really didn't do this). But I'll look through it tonight to see if there's a problem with it, I probably won't find anything but who knows, maybe I'll find something odd. I'd prefer not to pull the valve covers because I have to pull the A/C compressor and some other crap on the other side.

Thanks guys.

[VileZambonie]

You can send it. I'll fix it for ya

[TexasRed]

That sounds a little sinister.