What have you done to your square lately??

[Mr Clean]

Oh, um, is BB a reference to a doner truck?

I don't know. I bought the motor to put in the Extracab. I can run the numbers on the block. It would give what year the motor is...ish. I'll take some pics for you and get it pulled tomorrow. Is there anything else you might need from it? I know nothing about TBI. I planned on replacing the intake, and putting FAST EFI on it. Is there any computer parts you might need. The 87 Blazer that I used for the Mistress had TBI 305 in it. I'll be pulling all of that out because of the 383 don't need any of it.

 

[JamesSam]

I don't know. I bought the motor to put in the Extracab. I can run the numbers on the block. It would give what year the motor is...ish. I'll take some pics for you and get it pulled tomorrow. Is there anything else you might need from it? I know nothing about TBI. I planned on replacing the intake, and putting FAST EFI on it. Is there any computer parts you might need. The 87 Blazer that I used for the Mistress had TBI 305 in it. I'll be pulling all of that out because of the 383 don't need any of it.

I'll take all the electronics. The computer, the IACV, TPS, EGR, injectors, ignition coil, ignition module, distro, cables...what did I forget?

 

[JamesSam]

Seriously though @Mr Clean , Shawn, we can PM and discuss what and cost etc...

 

[Mr Clean]

I'll take all the electronics. The computer, the IACV, TPS, EGR, injectors, ignition coil, ignition module, distro, cables...what did I forget?

I don't have the 305 that came out of it. I gave it away to get it out of my shop. I can take pics of the BB and see if there is anything you can use. I have no idea what the IACV is.

 

[Camar068]

Here I thought the hardest part was just getting the dang ol oil pressure gauge hooked back up.. Yet somehow my whole cluster is not fitting in back in the dash. What am I missing here.. Sheesh. It's like the whole housing hits on top and bottom edges.

You must be registered for see images attach

Is it a tilt top forward and lift the dash a bit? Or a tuck under and lift the dash a bit? If you start cursing....stop for a bit.

 

[JamesSam]

I don't have the 305 that came out of it. I gave it away to get it out of my shop. I can take pics of the BB and see if there is anything you can use. I have no idea what the IACV is.

Ignition Air Control Valve. One of the dohickey's that plug in to the base of the TBI(carburator). Again, BB is what exactly?

 

[JamesSam]

Big Block?

 

[Mr Clean]

Big Block?

Yes Big Block

 

[Redfish]

@JamesSam if you go with that Big Block TBI you are going to have to swap your injectors into it. I am not sure about the regulator spring.

Have you done a rebuild of your existing TBI? It is not hard, the kit is not expensive and most folks report an improvement. You can watch a couple YouTube videos on it and get some idea of what you have to do and you will easily see why it might be a good idea. I got my kit from my local O'Reilly's.

 

[JamesSam]

Yes Big Block

I finally got what I knew I was missing. Sorry but nevermind. I am fairly certain a BB TBI wouldn't match up with my 350.

Would it?

 

[Mr Clean]

I finally got what I knew I was missing. Sorry but nevermind. I am fairly certain a BB TBI wouldn't match up with my 350.

Would it?

OK... no big deal just thought I'd offer. I don't know enough about TBI to know if they are interchangeable or not. @Redfish just said something about changing the injectors, but like i said I don't know enough about TBI to know.

 

[JamesSam]

OK... no big deal just thought I'd offer. I don't know enough about TBI to know if they are interchangeable or not. @Redfish just said something about changing the injectors, but like i said I don't know enough about TBI to know.

Same, unfortunately. I appreciate the attempt and communication. I am currently searching for TBI size specs...

 

[Redfish]

The TBI injectors are basically just On/Off solenoid valves. The fuel pressure is created by the pump in the tank and is regulated by the regulator spring located in the rear top of the throttle body itself. GM used different size injectors for each engine. I cannot tell you which size is for which engine or anything about flow rates without researching (Google!).

I can tell you that there are different springs for the regulator but you might run out of available fuel pressure if you try to go too far with the spring replacement.

This is honestly a pretty simple system when compared to more modern units. It is a limitation if you want to build a lot of horsepower, in stock form it is only going to flow (approximately) 450 cfm but it can be modified.

I am pretty sold on this system because I put a lot of miles on TBI 350 trucks back in the '90s. There are better systems but this one does work.

 

[bucket]

The big block throttle bodies are basically the same, but different. They have larger throttle bores, higher flow injectors (the small block injectors swap right in), a different IAC valve and the throttle lever doesn't have a provision for the 700r4 TV cable.

It can all be overcome and is a bit of a performance improvement. For someone that doesn't have much to fabricate with, the throttle lever is the biggest obstacle.