GM TBI color-coding

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JeepGuy24
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GM TBI color-coding

Post by JeepGuy24 »

OK, this might be a stupid question....but I just want to make sure of something. I got my GM TBI off of ebay, and saw that it had orange injector tops (the metal posts), so I figured it was the 55lb ones from the 350. I've seen the listings for color codes and GM TBI injectors, but the picture where they show you where the color-code is never shows up. I was wondering if someone could just clear up where exactly the color code is (is it the injector terminal posts?).

My other question is if anyone knows whether the injector pod from the 454 unit will bolt straight onto the small bore TBI. I have ported and polished the smaller bore TBI and would rather stick with its lower cfm because that is all I should need and I would rather have the throttle modulation at lower thorttle opennings.

Thanks
hudsonhawk
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Post by hudsonhawk »

The color codes should be somewhere on the injector themselves. They will have to be removed from the pod. The orange connectors are standard for all GM TBIs.

The pods are interchangable between the TBI bases.
'72 CJ-5 w/'83 AMC 258 running a late 80's GM TBI controlled by MegaSquirt.
donjr5
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Post by donjr5 »

On the metal rim around the connector pins there are dabs of paint (at least on my 40 lb--green/yellow injectors).
Hey HudsonHawk, sooner or later I'm gonna make an FWD meeting and meet you. My brother is the treasurer of FWD.
hudsonhawk
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Post by hudsonhawk »

Come on out.. I am the membership chairman.
'72 CJ-5 w/'83 AMC 258 running a late 80's GM TBI controlled by MegaSquirt.
JeepGuy24
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Post by JeepGuy24 »

Thanks guys. I actually used the serial numbers on top of the injectors to be safe. I did have the 4.3L injectors. Went to the JY today and got some off of the 350 and now about to clean them up. thanks for the help.

Another question for you TBI guys....

Did you run a flyback board or just put resistors inline with the injectors? I've heard both and was just wondering your opinion. I'm on a dirt cheap budget too, but also don't want exploding MS problems!
hudsonhawk
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Post by hudsonhawk »

I will probably get fried for this but I am running the injectors using the PWM of the stock unit. No resistors and no fly back board. So far it is working and have not had any issues in 150 miiles of driving and many hours of running in the driveway. But then I dont run around at WOT either.
'72 CJ-5 w/'83 AMC 258 running a late 80's GM TBI controlled by MegaSquirt.
JeepGuy24
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Post by JeepGuy24 »

This is in a Grand Wagoneer, and I baby the throttle to keep gas milage "up", so my 360 would see very little of anything over half throttle and very little high revs. It is run through the 727 which is a three gear, and highway cruising can be at somewhat high revs, but just relatively. I wonder how much the resistors would cost? (just to be safe)
russellmopar
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Post by russellmopar »

I got mine from Easy Pickin's. Crazy Ray's should have some too. I think I got mine off a honda civic. I followed the injector wires till I found a box that had wires going to all four injectors and one going to power. I don't think they charged all that much for it, probably thought it was a relay.


For non Baltimorons, Easy Pickin's and Crazy Ray's are U pick and pull junkyards.
1940 Ford Coupe 350 sbc
2 GM TBI's on an old duel quad Offenhouser 360 intake.
Heres my success story: http://www.msefi.com/viewtopic.php?t=7629

1969 Plymouth Roadrunner Convertible 440
Gm 454 tbi
kind of runs:)
JeepGuy24
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Post by JeepGuy24 »

I was just at Crazy Ray's this morning! My girlfriend needed a window crank and its tracking for an art project. I was also looking for spare injectors but they are cleaned out of 350 injectors, just a couple of 305s.

Do you remember what kind of civic it was? Or they are probably all alike. Guess I'll head down there tuesday morning and see what i can aquire. They are pretty good about letting you have small parts like that. Thanks for the tip.

So where are you in Baltimore? I live at Eastern and East Ave, which is like 1 mile from Crazy Rays, just gotta get through all the lights.
russellmopar
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Post by russellmopar »

I would look at alot of the four cylinder jap cars, I'm not sure it was a civic might have been a nissan(they look all the same to me).

I got the info from this post
http://www.msefi.com/viewtopic.php?t=3693
renns wrote:An easy way is to buy a resistor pack made for the job, and wire it in to the positive supply side of the injector circuit. Hondas have a nice resistor pack for four injectors, mounted in an aluminum die-cast body. They are usually mounted by the strut tower on the driver's side. Here's one for sale on Ebay now:

http://cgi.ebay.com/ebaymotors/ws/eBayI ... 7924534101

These units have four resistors wired in parallel, with a common connection at one end, and separate connections at the opposite end, five wires in total. Supply 12v to the common wire, and run the other four to your injectors. If you are running a v8, buy two.

Roger
I live about a mile or 2 away from Easy pickins, near Gunpowder State Park, at the end of Eastern Avenue away from the city.
1940 Ford Coupe 350 sbc
2 GM TBI's on an old duel quad Offenhouser 360 intake.
Heres my success story: http://www.msefi.com/viewtopic.php?t=7629

1969 Plymouth Roadrunner Convertible 440
Gm 454 tbi
kind of runs:)
cng1
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GM TBI color-coding

Post by cng1 »

> renns wrote:
> An easy way is to buy a resistor pack made for the job, and wire it in to the positive supply side of the injector circuit. Hondas have a nice resistor pack for four injectors, mounted in an aluminum die-cast body. They are usually mounted by the strut tower on the driver's side. Here's one for sale on Ebay now:

I've been running one of those units and very really are very neat and work
well.


(posted by email)
JeepGuy24
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Post by JeepGuy24 »

russel, do you think the VE of your 304 would have the same characteristics as my 360? They are basically the same heads if they the post-69 era ones with the dogleg exhaust ports. Atleast I've heard that they are interchangeable. I'm running an Edelbrock Performer intake on top of it but besically everything else is stock. I know a lot of other things go into determining the VE of an engine but I was wondering if you could give me any hints or share your table with me.
I'll probably try and head to Ez pickins tomorrow morning before work (only like a 20 min drive) and grab those injector resistors and find 55lb injectors. Thanks for all the help.
russellmopar
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Post by russellmopar »

I used the Initial VE Table calculator; http://www.megasquirt.info/manual/vetable.htm to generate a ve table using the info from this site, http://www.off-road.com/jeep/tech/engine/amc360.html.

It ran good enough for the around the block test we gave it on the Jeep.
1940 Ford Coupe 350 sbc
2 GM TBI's on an old duel quad Offenhouser 360 intake.
Heres my success story: http://www.msefi.com/viewtopic.php?t=7629

1969 Plymouth Roadrunner Convertible 440
Gm 454 tbi
kind of runs:)
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