TBI vs. Carb

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Princess Valiant

Princess Valiant

A.K.A. Rainy Day Auto
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So I have this 90 dodge ram with a 360 (5.9) and the TBI system.

It starts and runs good but this truck is a parts truck and must be parted.

So I have the idea of transferring this driveline to an older truck but should I get over the TBI Idea and use a carb or is a TBI something that might be handy ?

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Those early TBI systems were not great....save the hassle, if your not going multiport, just stick with a carburetor
 
TBI was just an electric carburetor with all the cold carb issues masked by the feedback system. and the idle was a solenoid acting on the throttle lever? K.I.S.S, Carb it or MPFI it and get away from the pod injector.
 
Tbi is all the drawbacks of a carburetor and all the drawbacks of mpfi, with none of the exclusive benefits of either one.

Dump it like a leftie leaving California.
 
TBI was NOT a carburetor in any way shape or form. TBI is not bad "generally" such as megasquirt or Holley, or FItech. The big drawback to early factory TBI was the electronics were just not up to modern standards. Jillions of those ran fine until they were driven/ towed to the junkyard or parted

It's a tough decision. I agree that ---- "Likely" not worth the trouble, and if you do have trouble, parts might not be great to find.
 
jos51700 said:
Tbi is all the drawbacks of a carburetor and all the drawbacks of mpfi, with none of the exclusive benefits of either one.

Dump it like a leftie leaving California.
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Lefties don't leave California. They love it there.
 
Dana67Dart said:
Disagree, they love it here in Colorado, cause their utopian dreams aren't working out in CA so they know it will work out here in CO.
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Yeah all they gotta do there is sit around and smoke weed legal like.
 
Alright so it looks like I'm going to **** can the TBI and carb it with a regular carb. The wiring in this truck is a mess, I'm surprised it even starts and runs.
 
Princess Valiant said:
Alright so it looks like I'm going to **** can the TBI and carb it with a regular carb. The wiring in this truck is a mess, I'm surprised it even starts and runs.
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Do you have a carburetor? I have a few if you need one.
 
The biggest downside to the stock TBI system is its not tunable at all. They were adequate for only stock engines and ran only marginally better (if at all) than any well tuned carburetor. They are not the same as the systems on the market today (sniper, fitech) as those are somewhat tunable. If you want fuel injection skip the middle ground and go multi port with a completely tunable stand alone (Holley hp, megasquirt, AEM Infinty, motec) You won’t be disappointed.
 
TT5.9mag said:
The biggest downside to the stock TBI system is its not tunable at all. They were adequate for only stock engines and ran only marginally better (if at all) than any well tuned carburetor. They are not the same as the systems on the market today (sniper, fitech) as those are somewhat tunable. If you want fuel injection skip the middle ground and go multi port with a completely tunable stand alone (Holley hp, megasquirt, AEM Infinty, motec) You won’t be disappointed.
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ant that the same efi that run so much better than a carb that all the magnum motors with 150,000+ miles still show cross hatch on the cylinder's cause raw gas didnt wash the oil away?? seen that info spread around a bunch on here,...now its no better than a wore out thermobog??? witch is it yall??
 
dirty white boy said:
ant that the same efi that run so much better than a carb that all the magnum motors with 150,000+ miles still show cross hatch on the cylinder's cause raw gas didnt wash the oil away?? seen that info spread around a bunch on here,...now its no better than a wore out thermobog??? witch is it yall??
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That's also a function of low tension rings, but please realize the magnums are multi port efi, a far superior system over throttle body efi

TBI was on the later small blocks, pre-magnum, which is what OP (original princess) is rocking. TBI is why people hated EFI for so long.
 
dirty white boy said:
ant that the same efi that run so much better than a carb that all the magnum motors with 150,000+ miles still show cross hatch on the cylinder's cause raw gas didnt wash the oil away?? seen that info spread around a bunch on here,...now its no better than a wore out thermobog??? witch is it yall??
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Post 18 read and understand it.
 
I am currently fighting with my son's '88tbi 318...
To make a long story short, it will probably have a carb on it soon!
 
Mopar Sam said:
I am currently fighting with my son's '88tbi 318...
To make a long story short, it will probably have a carb on it soon!
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Too bad it's not easy to put mpfi on it! Can't blame you for yanking that out
 
If you are going from TBI to Carb, sure would be handy if your '90 360 TBI already had the fuel pump eccentric on the end of the cam.

Then you can easily go to manual in the block fuel pump. Otherwise they make cam snout adapters to bolt up the eccentric.

Some TBIs had them, some not.

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(Lots of the TBI engines had the short snout cams.) Pull the fuel pump block off plate and see if the eccentric is in there.

Good time to check see how sloppy the time chain is too, by rocking the crank and watching the distributor rotor movement.
 
The swap to a 4bbl is getting pretty expensive these days. In your case even more so. When swapping a truckTBI into a car chassis;
carb and intake is just the beginning.
Now yur also talking;
a complete ignition system, with wiring, and
a low-pressure fuel system, and
a truck oilpan does not fit in a car chassis.
You still need to hook up the trans somehow, and
the KD linkage, and add air filtration.
The new intake may not have the correctly sized stat house/bypass spigots to compliment what your new chassis has; so you might have to fool with that; and,
after all that, once it's running, you still gotta tune it.

I'm not suggesting that you shouldn't go for it.
I'm only alerting you to the time and trouble you MIGHT be in for with the conversion. Your replacement chassis may already be somewhat compatible, but I sorta listed everything that I know about. There could be more.

BTWays
1) if you have to swap pans, you will need a matching pick-up, and you might as well replace the oilpump while yur in there.
2) just cuz the crosshatch looks great, doesn't preclude that the she don't need a valvejob.............. or some other work, so before you yank it out, you might want to do a LeakDown test, or at least a Compression test.
3) And if it currently runs, then toss in an oil-pressure test.
 
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If the truck you are putting that motor in is a 72 > model truck, it should bolt right in with the same motor mounts and oil pan. Ditch the TBI, and bolt a stock cast iron 340-360 intake on it and a known good carb. I have an 88 with a 318 and the same crappy TBI system. I have a low mile 98 model 5.9 Magnum and all the wiring that I'm gonna swap into it and have the MPFI. Lotta dang work for a firewood truck.....but will be well worth it! :)
 
TBI was pretty good when it was new,
marginally better than a carb, because atomization at slow rpm was better.
But EFI was evolving so fast, it very quickly became dated. And, it seems like, TBI did not age well.
 
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