OK.... so I was a little optimistic on the 7 cylinders. It was running as strong as it was pre-rebuild.... on 5 cylinders. yes.... that is correct, 5.
OK.... so I was a little optimistic on the 7 cylinders. It was running as strong as it was pre-rebuild.... on 5 cylinders. yes.... that is correct, 5.
Pulling the valve covers tonight. I think I have the intake rockers too tight, bleeding off pressure and ocasionally backfiring through the intake.
Stupid old cars and completely changing everything.
On the bright side, it's still probably faster than a FRS.
Bobzilla wrote: RIGHT NOW.... on 7 cylinders. Argh.....
LOL nothing more expensive than a cheap vette
in all honesty, this is really a great thread and Im glad to see all the progress! Nice work!
Other than the little engine issue that popped up, I am enjoying this thread . . . So much so that C4 vettes are on the radar . . . Mrs. Zero approved!! 
Bobzilla wrote: Pulling the valve covers tonight. I think I have the intake rockers too tight, bleeding off pressure and ocasionally backfiring through the intake. Stupid old cars and completely changing everything.
I had a problem sbc I just could not get the valves right on. I finally used a scope camera to look in each cylinder while I was setting them.
rotard wrote: On the bright side, it's still probably faster than a FRS.
It was quicker than it was before the rebuild running on 5 cylinders. Once it's running on all 8 this car is going to A.) kill me, 2.) make me giggle like a group of high school girls, iii.)get me thrown in jail the first week I drive it or k.) all of the above.
This car makes me giddy and scared all at the same time.
4cylndrfury wrote:Bobzilla wrote: RIGHT NOW.... on 7 cylinders. Argh.....LOL nothing more expensive than a cheap vette in all honesty, this is really a great thread and Im glad to see all the progress! Nice work!
Ya know, I knew that coming into this deal. I'm a little over $6k total in the car as it sits right now including purchase price and repairs/upgrades. I'd have paid $7-8k for one in pristine/great shape and itwould have likely been an auto non-Z51 car. It's worth the (lots) of blood, sweat, tears and (continuous stream of) Profanities to have it the way I want it.
OK, 2 months later and I'm still fighting this damn thing.
car starts,runs and drives great..... on 5 cylinders. I've changed injectors from good cylinders, injector connectors, plugs, wires no change on any of it. There is fuel on the plugs, and spark at the end of the wires. I've changed to good plugs multiple times. No change.
Fuel pressure was low (38psi KOEO, 35psi engine running with the AFPRcranked to the max) so I installed a new Walbro 255 in tank pump. Pressure is where it should be factory and I can still turn it up if need be. There is fuel to the dead cylinders, you can smell it on the plugs. Like I said before, I swapped injectors (new Accel 24lb) from good cylinders and no change. Tried changing the injector plugs no change. The good cylinder still fires, the bad cylinder does not.
Ran a compression test. Worst cylinder was 150psi dry, best was 158psi dry. Best was one of the dead cylinders, worst was one of the good ones. Ran a coolant system pressure test. Had a slow leak down(10 minutes to lose 5psi) that I later tracked down to a loose hose clamp off the t-stat housing.
So what the hell am I missing? I've got fuel, spark and compression but I am still running dead on 3 cylinders. What did I do wrong? Thoughts? Suggestions? I'm at a loss here.... completely lost.
Dead lifters? Given the randomness, that is where I would look first given all the previous information.
no valve train clatter, and compression is spot on the dead cylinders. Someone else mentioned a 4-7 cam. I have not checked that yet.
ok, the exact cam is: CompCams CS-266H-R14, .500I, .510E, 114* lobe sep, 266I/276E duration.
I am pulling my hair out with this thing
Only thing I can add is firing order? Sure, dumb question, but when things go wrong sometimesthe obvious gets over looked. Can't think ov any other reason? Are the injectors firing in the correct order?
Checked, rechecked and checked again. Injectors are batch fire, so one side at a time fire off. It's how I can swap plugs on o e side st a time.
It's got to be ignition. Can you pull the spark plug wire from the dead cylinders and get a good spark on a plug grounded to the block?
Bobzilla wrote: This weekend was going great. Got the oil pump primed, harness connected, connectors fixed/replaced, miscsensors installed, driveshaft finished and installed, trans linkages done, coolant hoses/radiator done, intake down, fuel lines finished up and routed.... dropped the distributor in and I'm missing something..... Crap. The connector that runs from the main harness to the ignition module for the ECU to control the timing I left on the old core. Went to Oreally's to see if the core was still there.... it's been gone for a while. So..... I'm looking for one used because the ONLY 2 left are on eBay new for $125.
Could it be the connector? I know you said you had to jury rig this thing with a diff dizzy.... only thing that occurs to me that you havent checked
It's not "jury rigged", it's actually a fairly common swap. I'm leaning towards the diet being 180 off. About to go out and try that.
I was just going to suggest that the distributor is out 180. It has to be a timing/firing order problem. Do you have one of those caps that they organized the plug wires so they don't cross? I ran in to one of those once and lets just say it really annoyed me.
Wait... . . Is there a "limp mode" on that car?
Obd ... "limp mode" is the driver being nice when it's broken!
OK, two weeks later, still fighting it. 4-5-6 are still no go. What I've done:
Swapped injectors.
Swapped injector wiring (no change, dead cylinders still dead, good cylinders still good)
changed wires (new Accel custom fit wiring run to not touch anything)
checked, rechecked and checked again firiing order
readjusted the rockers
checked for bent pushrods.( none bent}
Measured valve openings (all matched)
Changed plugs
checked plugs
changed the timing
turned the dist 180*
put in new 255lph fuel pump
checked compression
checked fuel pressure
I'm pretty much out of options/ideas. I'm down to wondering if the cam is not installed correctly or.......
Did the cam round it's lobes off? Sounds like my cousin who installed a new cam in his old 307 powered chevelle and promptly rounded off the cam lobes.
Time to put a dial indicator on the valves and measure lift and duration...
Either that or a leakdown test?
The cam woukd be good to check Bob... Sorry to hear going 180 on the dizzy didnt give you any love.
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