I'm presently rebuilding an SBC 406 and i'm wonderin it it's possible to run it with my TBI unit installed presently on my LO3 ?

 

you will need larger injectors and a computer mod for sure before it will run...

 

and add to that a GM TPI or aftermarket TPI fuel pump.

 

Do you think it's well worth the time and money spent or it would be better to go with a carburetor ?

 

Depends on a few things, such as emmissions requirements, what tools you have, and your ability to do PROM tuning. If you don't have emissions you could throw a carb on there and be done with it. If you want to go a little more in depth you can go with TBI but there is a lot more involved. In the end, if you get that PROM dialed in, you should be able to squeeze some more power out of it and be MUCH more efficient. With fuel injection you have much more control over your engine, you can watch what it's doing on a computer screen, take a degree out here, add a degree here, tweak fuel tables, etc etc, but that can take many months to perfect.

I would look for BBC injectors and a BBC TBI unit, which has bigger bores.

 

Look into the EBL system. All your answers lie there.

http://www.dynamicefi.com/


All the other stuff you need is just easy mechanical stuff.

 

You can run a TBI on a 406, but you really need to decide what's important to you before you make your decision.

TBI will run smooth and reliably, have great throttle response, and get better mileage than a carb. The problem you're going to have is that, even with the biggest throttle body and injectors available, and running as much fuel pressure as possible, you're still going to be starved for air and fuel in the upper rpm ranges; you'll be giving up 20-50hp (at least) to the same engine with a well-tuned carb.

Additionally, the throttle body on your L03 isn't the biggest one available; you'll need a Holley 670, or a bored-out 454 TB.

I'm wondering, though, are you wanting to run the TBI you have to save money? If so, and if you haven't yet bought the 406, you can go with a 350 instead, and still stick with TBI. Fast355 has gotten some great results that way.

I'm a big fan of 406', and have run them in several carbed applications with great success and satisfaction, but you're spending a lot of money for those extra cubic inches, then choking them down with TBI induction. I just don't think the performance difference between a 406 TBI and a 350 TBI is worth the extra cost. I think the choice would be 406-carb, or 350-TBI, unless you're going to use the 4-injector drivers on rbob's EBL. If you do, you can go with a 4bbl throttle body that resolves all of the airflow and fueling issues inherent in a 2bbl TBI..

Just my suggestion.

 

I have the 406 since the past 6 months , but with your advices I think I'll go with a carb ... Thanks a lot

 

I'm still debating on putting a CFI unit on my 406...if I can FIND ONE for a reasonable price! For a fuel injection system people hate so much, you would think I could find one easy...or someone would just like to get rid of it