FNG to GearHead EFI & TBI. Just finished a project (with a lot of help) restoring an '80 Jeep CJ5 with SBC TBI. Joined to READ PREVIOUS POSTS prior to posting any questions. Currently having issues with the timing on my new ride...
Advanced 4* (installed at 2* advanced - Cloyes 3-Keyway)
Overlap: 30*
RPM Range: 2500-6500
Distributor/Ignition (Standard Part #, unless otherwise specified):
(Small) Cap: DR458
Rotor: DR326
Ignition Module: LX340
Pick Up Coil: LX342
Coil: MSD Blaster SS
Wires: SummitRacing SUM-868836R 8mm
Plugs: ACDelco R45TS
ECM:
Service #: 1227747
Pistons:
Keith Black KB159-030 hyper-eutectic
12cc dished
Heads:
GM 333882
76cc
Intake:
Edelbrock Performer RPM Air-Gap 7501
Exhaust:
Hedman 69516 Headers - 3" Collectors
MagnaFlow 12649 Mufflers 3" in/3" out
Sensors/Other (Standard Part #, unless otherwise specified):
IAC: AC1
ECT: TX3
TPS: TH41 (maybe TH42)
MAP: AS5
O2 Sensor: Bosch 13077 (I've been having acceleration, or lack there of, problems since installing-Didn't have the $$ for ACD 213-632 - originally had SG91)
Fuel Pump: NAPA P5001
Alternator - 7802NB - reman - "high output" - single wire (looking into converting this)
SM465 Transmission
Cast Iron Top Cover (would love aluminum if anyone has any leads)
Gears: 6.55/3.58/1.70/1.00/6.09(R)
NP205 Transfer Case
High: 1.00
Low: 1.96
Twin Shifters
Axles Front:
'76 Scout II Dana 44
4.56 Powr-Lok
Disc brakes
Rear:
'76 Scout II Dana 44 Tubes
Case/center section/pumpkin - '78 or '79 Ford D44 HP
Had to use a high pinion d/t short wheelbase of CJ5 and the rear drive shaft (14") angle.
Can supply any other info if curious, needed, etc.!
If you see anything that jumps out at you please let me know! I was having some issues with cold starts, once about every 3 or 4 I would have to keep the RPMs around 2k or it would die. I'm not too sure about the ECM, the gentleman that put together the TBI kit had all the information on the build, and sent me a new chip after describing my issues. Seems better than it was but something still isn't quite right.
Long story short, I moved for school before the break-in process, my knowledgable buddy (mostly Ford, admittedly) finished for me, then I had it shipped.
The first couple weeks I had it, it seemed to be running great (other than the occasional cold start mishap). Now, when I get up around 2500 RPM it's hesitating/stumbling with acceleration (only when under load). I started messing with the timing, found the initial timing (at idle ~950 RPM), with ECM disconnected, it was advanced 4*. It seems like some "experts" say it needs to be at 0 with ECM unplugged, and others say SBCs with bigger cams like upwards of 12*. Anything under ~7* advanced with ECM unplugged, it will not idle without giving it some throttle.
Vacuum is adequate (forgot to mention - no vacuum or mechanical advance), fuel pressure is adequate, spray looks fine.
I read that the "heated" O2 sensor that came with the TBI kit is pretty shotty and does not actually heat up efficiently. Seeing as that is the only real feedback on fuel/air mixture, I thought that may be contributing to my stumble during acceleration. Since replacing it, if I give it anymore throttle than just enough to get it moving, it jerks like crazy...
As you can see, I have a few wrinkles to iron out, but excited to learn during the process. Rome wasn't built in a day, right?
Attaching some pictures, and a video (before it was "done") of it running...
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