??? your cam is so big it won't idle to let you run some tests? I've run .675+ lift solid cams that would idle fine. Yes you had to raise the base idle, but still. What kind of vacuum at idle are you pulling?
This was my 85 notch.....before the ex sold it.................... to pay for her divorce lawyer..... vs. me............ for $4000...............
985 gt 347 11.5 to 1 J&E , Eagle crank, .675 solid roller lifer cam, TFS high ports, victor jr , all ported, BG Cold Claw, Holley Blue pump with 8-an braided lines, main & stud & rocker girdles, ARP studs throughout, MSD Ignition, 1 3/4 long tubes, X pipe, tko, 31 spline auburn pro w/4.56 gears, subs, adj upper and lowers, Eibach Drag pack, 6 pt cage, WEld draglites -skinnies up front and 15x10 with MT 28X10.5's, custom interior 2600lbs. best time 10.26 @130 442 rwhp 505 rwtq
An engine that runs so rough that it shakes everything has problems other than a wild cam. You need to do some serious troubleshooting to find and fix the problem.
You guys with idle/stall problems could save a lot of time chasing your tails if you would go through the Surging Idle Checklist. Over 50 different people contributed information to it. The first two posts have all the fixes, and steps through the how to find and fix your idle problems without spending a lot of time and money. I continue to update it as more people post fixes or ask questions. You can post questions to that sticky and have your name and idle problem recognized. The guys with original problems and fixes get their posts added to the main fix. :
It's free, I don't get anything for the use of it except knowing I helped a fellow Mustang enthusiast with his car. At last check, it had more than 125,000 hits, which indicates it does help fix idle problems quickly and inexpensively.
it could be a dozen things from a bad balancer, to a vacuum issue, to broken or misadjusted parts, timing, fuel, bad tune, you name it. Looks like he doesn't know the specs of the cam, but it's just a 306 with a mix match of parts making up the HCI.
Bottom line is, he's got a problem that needs to be addressed. If he can't run the codes because it shakes so much, how do you drive the thing. He needs to follow each step on jrichker's list to diagnose the problem before he starts breaking stuff.