Got first run in. Ran 14.6. Rapped it to nearly 6000rpmshifting thru gears. Not sure if that's when I hurt it but then 2nd run while doing burnout something went wrong. Running very bad like it was firing on half the cylinders. Got pushed back and in pits I checked timing. Thinking it jumped but #1 at TDC, rotor pointing to #1 and timing mark lined up perfect. It will start just runs crappy. Maybe a spring or valve or bent pushrod. I will tear into it this weekend. Any thoughts from you guys ??
Some info about the engine would help us help you. Was it ever rebuilt, what cam...........etc...etc?
What kind of ignition do you have? If you have points & condenser, it could just be a bad condenser. I had something very similar happen to my 69 SS396 at the track one night. Made a run, everything was fine. I got halfway down the track on my second run and it started missing & backfiring. We tried everything to fix it and as a last resort we replaced the condenser and it was good as new! I wish we would have replaced the condenser first...
Bent pushrod or broken rocker arm, or both. Never hurts to place leads to other threads you have about your car: http://www.v8buick.com/index.php?threads/got-a-little-track-time.332386/ http://www.v8buick.com/index.php?th...-in-the-mild-built-engines-350-or-455.333148/ I'd try to keep ET threads together if you want people to follow them: http://www.v8buick.com/index.php?threads/new-best-time-at-track-for-me.332771/
I've had that happen a couple of times Bill, the cars (both Oldsmobiles) would run like crap or not at all, but would idle OK.
You'll have to do some diagnosing. If it's bone stock turning 6k is asking a lot. Try to figure out which cylinders are missing. Maybe pull the valve covers. Any noises or changes in oil pressure?
I blew a Dynomax muffler apart when I was in high school , power wire came loose going down the road then made contact but only after I had pumped the throttle a few times, loudest thing I've ever heard ha, scared the crap out of me
Back in the 80's I was out at the Greer Dragway on "Grudge Night" in my 69 SS396 Chevelle. I made a pass and everything was fine. On my second run I got halfway down the track and it started running like crap - missing, backfiring, etc. I got it back to the pits and we started trying to figure out what was wrong with it. We couldn't fix it so I decided to try & drive it home. I got it out on highway 357 and it was running like total crap - still missing with an occasional backfire. Then it stopped running altogether so I pushed in the clutch and tried to start it while I was coasting down the road. I'm sure I pumped the gas a few times and when it started there was this tremendous explosion! Scared the crap out of me. I coasted to the side of the road, got out and looked under the car. One of my Turbo mufflers was split wide open at the seams. Oh yeah, and the problem turned out to be a bad condenser... at the time a 79 cent part.
Not stock. TA 290-94H cam .030 bore TA Pistons Stage 1 intake Everyday Perf. Quad jet Dbl roller timing set Ignitor 2 distributor kit ported stock heads cast iron 3;42 gears. Stock exhaust
I missed a 2nd to 3rd shift (turbo 400 BB) once at 6000 RPM (built motor). The oil light came on in a split second, shut it off pretty fast. Got home on a flat bed and took PS valve cover off. Found a bent push rod. Easy fix. Do yourself a favor and don't start your motor till it's been fixed. If you start it before the fix, more bad stuff will happen.
Those plugs don't look bad. No physical damage. Typical stuff when trying to run or start a cold engine without getting it warmed up or trying to keep a rough engine running. You said springs and pushrods look ok. Did you try cranking the starter(remotely) while watching the valves/rockers moving up and down without the plugs in? After watching them move for a few rotations you can pick up on if there is a problems with one or more valves. Also does any water come out from a particular cylinder? If so head gasket probably. As mentioned elsewhere do a compression test. You say you confirmed the timing didn't jump. By checking it with a timing light by cranking the engine? Also check, if you didn't, that 0 on the timing cover lines up pretty close to when the dist rotor lines up with #1. Generally speaking if the timing chain jumps timing will retard about 16* out of nowhere but the car will still run but be hard to keep running but will not run roughly. Though I doubt the timing jumped because of the double timing chain but you never know with the other parts. Dist gear maybe? One part I did see that raises my eyebrow is the Ignitor II box. There's been multiple complaints about them so that is the direction I'd go in if the external checks of the mechanical systems check out. Re-install the points or something else in the dist. even if it is temporary before pulling the engine apart any more. Google Pertronix Ignitor problems.
[ One part I did see that raises my eyebrow is the Ignitor II box. There's been multiple complaints about them so that is the direction I'd go in if the external checks of the mechanical systems check out. Re-install the points or something else in the dist. even if it is temporary before pulling the engine apart any more. Google Pertronix Ignitor problems.[/QUOTE] It was the Igniter magnetic wheel. Two of the magnets fell out. Never would have noticed it till I flipped the distributer over while inspecting. Explains no fire to # 7 and 2
Good find. Hope it works out. I had an Ignitor III and it didn' even make it through break in. I bet you had the "pucker" factor in full effect when expensive thoughts ran through your head!
There are a number of documented incidents with magnets coming loose on those things. Glad that's all it was, easy/inexpensive fix.
