TBI... AGAIN

[mrtazwrench]

last weekend i picked up a complete running chev caprice former police car with a 350 TBI, i plan to use the parts to put TBI on my 87 J20, i don't have ECM # or any of that yet, i'll post that info when i get it. i plan on using the sensors, wiring and anything else i can from the caprice, looking for ways to do this swap as cheap as possable. i'm also not sure yet if i'll do ignition control also. right now after doing searches here i know i need a chip, TB adapter, fuel pump, and speed sensor, just looking for any input to make this swap go well. thanks in advance to anyone that can help.

[Serious Johnson]

That should be the '7747 ECU -- perhaps the most hacked computer on the planet -- wonder what tweaks were in the cop-car version? I would certainly go ahead and do ignition control, and knock/speed sensors as well. Hell, even if it's not perfect it's still a fair starting point and allows you to ditch the silly ICM. I ran a stock '92 Chevy 1/2-ton chip in mine once for testing purposes, and it ran almost as well as the stock carb/ignition, so it's not a live-or-die thing.

I have a nearly new Bosch in-line fuel pump that I'll probably never use again (S-10 tank behind the axle with integral pump in place now). It's yours for shipping and the price of a case of cheap beer.

}}}}

[mdill9]

The cars did not use the 747 I have only seen them
in the trucks/vans.

Mike D.

[JeepinPete]

Serious, if he doesn't jump on that, I would like to. I am doing the same swap in a couple weeks, the last thing I need is a fuel pump...

[pb]

As mentioned you don't need the speed sensor, can't hurt though. The knock sensor is not necessary - it may pick up normal 360 noises and try to adjust for it.

Also, there are some differences in harnesses for each type of computer, so try to get the harness and computer from the same vehicle unless you are making your own.

[mrtazwrench]

Originally posted by Serious Johnson:
That should be the '7747 ECU -- perhaps the most hacked computer on the planet -- wonder what tweaks were in the cop-car version? I would certainly go ahead and do ignition control, and knock/speed sensors as well. Hell, even if it's not perfect it's still a fair starting point and allows you to ditch the silly ICM. I ran a stock '92 Chevy 1/2-ton chip in mine once for testing purposes, and it ran almost as well as the stock carb/ignition, so it's not a live-or-die thing.

I have a nearly new Bosch in-line fuel pump that I'll probably never use again (S-10 tank behind the axle with integral pump in place now). It's yours for shipping and the price of a case of cheap beer.

}}}}sounds like a good deal on the pump, may be a bit before i can get back to you on it. i have the fuel inj line and clamps at work, always use those clamps on leaking mopar trans lines. can the return on the o.e. filter be used as the return from the throtle body and what is a good filter set up? thanks for the replies so far, keep the info comming. i want to keep as much of the origional stuff as i can in the swap, and don't plan on starting on the truck itself until i take the truck off of the road for the winter. the info i'm looking for right now is using the o.e. dist. and feedback control, my motor only has 63K on it and i would prefer not to change the dist. and risk gear issues. thanks again to those that have replied so far, and i'll post more when i inventory my parts.

[Serious Johnson]

The stock return is probably good enough, as long as it has no added restriction from kinks, etc., but I wouldn’t swear to it. I went ahead and ran new 3/8" supply from the tank for peace of mind, then used the original (5/16"?) supply as a return. I plumbed-in a generic replacement metal filter for a TBI Chevy, mounted to the frame rail up by the x-fer case with a Miata J bracket. When I was using the in-line pump I also had a cheap plastic filter on the suction side to protect it from tank debris. I think that’s still on the old pump if you want it.

I still use the stock distributor (w/ TFI) in mine, with the weights removed, advance plate pinned in place, & control box eliminated. ECU handles the entire spark curve. The knock sensor seems to work well on mine, though Paul is probably right about it sometimes pulling timing out unnecessarily. I can certainly feel the difference between 85 & 91 octane during heavy towing, but then I’m not running stock compression or cam, and my old Jeep is extraordinarily smooth & quiet. A speed sensor mainly allows full fuel cut when coasting in gear, as on a long downhill, thus potentially saving some fuel -- probably not a whole lot. I guess it may also do some control functions on a modern slushbox.

}}}}

[mrtazwrench]

anyone have a wiring diag for the ignition system? when i get to the point of finding a chip, has anyone come up with a stock 360 program i read about in another post? the motor is staying stock, minus air pump, and flowmaster on on the stock y-pipe.

[mrtazwrench]

thanks for the diag, the truck will be off the road for the winter early next month, and i hope to get started on this, i just need to sell some parts so i can buy what i don't already have. anyone have the part # for the adapter from the tbi to stock 2bbl manifold?

[mrtazwrench]

Originally posted by The Anti-riced:
The 1228746 has an air inlet temp sensor. IIRC there are only one or two wires that are different between the 1227747 and the 1228746. The plugs are the same and the wiring can be modified pretty easy. Not sure if the car harness is shorter than the truck harness.started to do tear down on the parts vehicle today, it does have the 1228746 ecm, i'm hoping to find a buyer for the motor before i tear it down to the point of not running.

[mrtazwrench]

got everything off of the parts vehicle, and my J20 will be off of the road for the winter next week, so hopefully soon i can start the install.

[madmule]

Mrtaz I'm going to be doing a TBI soon myself. Maybe we can keep in touch and help each other out. I have a bud that's going to be helping me, he's a Pro mechanic, and recently did a swap out on his 71 F*rd Bronco. 302 with whatever type of injection they use it has a computer etc. Between all of us, including IFSJA of course, we should be able to make em' go.

John

[ November 19, 2005, 05:31 PM: Message edited by: madmule ]

[mrtazwrench]

there is a link to the international site around here somewhere too, they have some very good info there.