Possible 350TBI Conversion Problems

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Mar 28, 2012
I am in the process of putting a 350TBI into my 1973 FJ40. The donor vehicle was a 1992 Suburban with an automatic tranny. The tranny I plan to put in is a SM465. A mechanic buddy of mine said that I might have some problems since I am not using the original tranny to the CPU. He said that I might need to chip it in order to get the CPU to work correctly. I didn't need to hear this as money is tight enough as is!! Any words of wisdom would be greatly appreciated!!
Chip it...NEVER

It depends on what harness you are using? If you are using the stock one from the truck. I have never had a problem and we have put 4 Complete 4.3L with TBI's into our HEEPS. I never did anything but ground out the neutral safety switch when we ran across it. I can send you all sorts of TBI info.. Just PM me ....:D
I'm rewiring the whole thing!! I have decided on Painless for the body, but I am still undecided about the TBI harness. So, are you saying a good wiring harness will take care of any issues I might have between the tranny and the CPU?? I've heard good things about Howell, but then again I am on a budget!!
Yes, you can do a TBI harness with or without Speed Sensor.. And i care less if others say you cannot.. Been there doing it.. look at the Black HEEP on my website... Also Howell is/are/always will be the TBI experts.. I do recommend the cal-pack and u can find manual chips used for cheap
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My guess is that Copper204 does not know ALL the things a VSS does, and does not know how well his rig would run if he had a VSS (yes, they get by without a VSS, but that's about all). You should talk to Stealth Conversions about a metric 2 pulse VSS that goes into your speedometer drive. The problem with the Howell harness is that he wires them for NOT using a VSS, then once you realize your rig actually would run alot better with a VSS, your stuck.
Like I said in Post

Like i said in prior post. there are those who differ in opinion. But I have installed over 15 Howell Jinjection TBI system. And each one came with a speed sensor. And as i stated. some believe you need one and some believe you dont. I use them, but have had a couple who were convinced not to use them, since they are rock buggies. But to make an unsubstantiated statement is incorrect. the following is a picture of just one HEEP in my driveway of 5 sitting out there with either a TBI or in a couple cases EFI. None of them came stock this way. But I will sit back shut up and let others direct you that are apparently more knowledgable.

QUOTE directly from Howell website in regards to the Harness I was trying to refer you too:

""Part # H243

Engine wiring harness for adapting production GM V-8 and 4.3L V-6 engines into pre-computer vehicles. Two styles available for both 454 and small block V8/V6 applications, 36" length from engine to ECM connectors. Includes emmission connectors to match pickup truck and van engines from 1987 to 1995. REQUIRES vehicle speed sensor and park/neutral switch (or manual transmission PROM) to be 50 state legal. Utilizes pickup truck ECMs 1987-1995 for proper function. "

Picture of one of mine-
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No argument from me, I'm glad Howell finally got onboard!!!!!

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