4.3 TBI swap timing

kaiser715

kaiser715

Doing hard time
Joined
Jun 1, 2006
Location
7, Pocket, NC
I am doing the 4.3 TBI swap on my '73., but for several reasons, am thinking about not using the computer controlled timing, just leaving vac/mech advance as-is.

Would I just leave all the distributor wiring disconnected in the 4.3 harness, and D5 (the bypass wire), by not being connected, let the computer do it's thing, and not look for input from the dizzy? I've googled, found several mentioned keeping 'manual' timing, but they don't say how/what they needed to do or not do.\

DP
 
Why?
 
IF you are not going to run ECM timing you need to carb it.
It can be done, sort of, without but you'll risk leaning it out bad.

The only folks I know who have successfully done it have run a third party spark control and referenced independent.
 
Contact the guys at Howell enginering they know all their is to know about the 4.3 swaps
We just put one in a sammi and they were a huge help !!!!!!!!
 
You dont have to use the computer timing. Get your ecm from howell FI and they take all that out and will burn you a custom chip. Run HEI dizzy with it and you will be in business. With the howell ecm you wont have to run a knock sensor either.
 
Why? Mostly kind of in a rush here. Need the Jeep running for a trip in early Oct. I just don't want to screw with my distributor (locking down vac/mech advance, etc), both due to running out of time, and not wanting to make this swap so "permanent" -- I got other ideas down the road.

Right now I'm borderline between giving Howell a call about an ECM, and sticking a 2100 on it. I have the TBI harness sorted out, all the parts lined up, and swapped my manifolds over (to 2v) last night. But...I only have 4 weeks to get that and a lot of other work done.
 
kaiser715 said:
Why? Mostly kind of in a rush here. Need the Jeep running for a trip in early Oct. I just don't want to screw with my distributor (locking down vac/mech advance, etc), both due to running out of time, and not wanting to make this swap so "permanent" -- I got other ideas down the road.

Right now I'm borderline between giving Howell a call about an ECM, and sticking a 2100 on it. I have the TBI harness sorted out, all the parts lined up, and swapped my manifolds over (to 2v) last night. But...I only have 4 weeks to get that and a lot of other work done.
Click to expand...

another option,just run a Q-JET and install it backwards,they make a kit to do this. Hillbilly FI and works like a champ, Chris Durham won the first ever rock crawling comp. with this setup.
 
I have not yet figured out how that works. I know Howell normally does not use the computer to control timing, but they still have to pick up a signal from something/somewhere to fire the injectors in relation to spark timing. Maybe someone who has a Howell system may be able to fill in the blank spots. Good Luck! :)
 
Again, Why? I have been running a TBI for years with no issues.
 
Welp, I decided that I will tie in the distributor, and do the ECM controlled timing -- AFTER the trip...for now, I snagged a 2100 and will run it for a few weeks, then back to the TBI swap.
 
For TBI do it yoruself....all the software is free
WInDLL
 
kaiser715 said:
Yeah, but as i understand it, you have to have an eeprom reader/writer
Click to expand...


Moates flashburn is $85 then the hardest part is desoldering the factory prom socket and soldering a zif socket onto the board. Ive soldered before but never desoldered anything and I managed to fix up two ecms one for myself and one for zombhnter on this board. The flashburn will erase and program eeproms. It has free software from moates and tunerpro rt is free also (if you pay the $30 registration you wont have to wait 10 seconds everytime you open it, depends on your patience to cheapness ratio:) )

I have about $350 in tuning stuff total. $85 for the chip burner, $50 in chips so ill have extras in case I fry one somehow and for both myself and zombhunter, and roughly $200 in a wideband air fuel ratio gauge for when i start hardcore tuning. Of course I justifed the wb gauge by saying I can use it to dial in the carb on my Fairlane too! So far Ive just made mostly minor changes on my TBI ford motor, stuff like Idle settings, "accelerator pump shot", and "power valve" settings to use carburetor terms. I did play around with the timing a lot however since the ford 351M and the chevy 350 that my computer came from need REALLY different timing maps.

Thirdgen.org (camaro site) and fullsizechevy.com have great info on tuning TBI and Binderplanet.com has great info on getting it to work on non-gm engines as well as tuning info. Binderplanet has the info on soldering the zif socket in a FAQ.
 
Here's a little additional info on the chips... mostly stuff I learned from Caver Dave and Binder Planet.

I think this is the best and easiest way... I did no soldering or desoldering at all on the ECM. I modified the carrier (little plastic thing the chip sits in) and used a 27FS512 chip. A little bit of soldering is required on the chip itself. All the details are in this link: http://www.binderplanet.com/forums/showthread.php?t=80053

I made a fixture for my milling machine for cutting the carriers, and I would gladly do this for any of you at no cost. Also, if the soldering intimidates anyone, I would gladly do that for you too. I did a considerable amount of curcuit board soldering when I worked for IBM.

Hope this helps someone. :)
 
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