I was wondering for the ones that have 350 tbi's in their cars whats your guys MPG since i am gonna be doing that swap and was thinking of the mpg i am going to be getting

The MPG will have more to do with the cam choice and heads than the extra displacement. I was able to get an average of around 28 MPG out of my old 350 in mostly highway driving. At the time, it had an edelbrock performer flat tappet cam (204/214 duration with a 112 LSA) and vortec heads. If you want to get good fuel economy, a set of GMPP vortec heads and a small cam is one of the best ways to go.

If you will be using an unmodified LO5, the fuel economy should be similar to what you have now, but maybe slightly less. Its essentially the same as an LO3, but with a flat tappet cam (in the truck motors), and 45 more cubes. The cam that comes stock is a teeny-tiny one, so you wont get a dramatic increase in performance. But, you can install the engine without the need for much tuning.

I average 15 per EBL but I need to check that vs. odometer read and fuel used. I suspect it may be a tad higher. I run 80 lbs inj at 19 lbs FP with VAFPR so the injs may hurt mileage. 3.07 rear manual 5 speed.

I am gonna swap a L98 block but bolt my tbi to it and a tb spacer and also the injector spacer

Instead of making a new thread I decided to bump this one and ask if I get a ebl system I would get more mpg as if I just keep the tbi stock or or not.

The EBL is a more efficient calculator then the stock TBI ECM, so yes if tuned it will gain some mpg.

Alright thanks that's exactly what I want since I am gonna have his car as a Daily Driver and mostly street driven. If any one has a 350 tbi wih ebl can you please post you street mpg you are getting also the mods you have done to it.

Bump

Anyone can post their 350tbi mpg

I get about 16.5 most of the time. I don't run city and i don't run much highway. Mostly rural driving.

Mods;

1991 Camaro RS
Engine:
SBC 355; Vortec Heads; Holley 2" TBI w/ GM Injector Pod; GMMP Vortec TBI Intake Bored out to accept 2" TBI; MSD 6A; Comp Cams XE262 .464/.470 lift - 218/224 dur@.05 - 114 lsa; Comp 1.6 Roller Tip Rockers; Comp 26981 Beehive Springs; Granatelli 255lph pump; Aeromotive VAFPR
Exhaust:
1-5/8" SLP 409 Stainless Shorty Headers w/ A.I.R.; 3" Aluminized Tubing; 3" Catco Cat w/ A.I.R.; Edelbrock RPM Series Muffler 3" in - (2) 2.5" out
Drive Train:
'94-'97 F-body T56 Trans; 3" AL DS; Torsen LS rear diff; 3.23 richmond gears
The Brains:
EBL; Zeitronix WB; Type 'K' EGT

Oh ok thanks so I should expect around 15 in street since I'm just gonna have a stock L98 block with full exhaust and ebl. Or do you guys think vortec heads is what helps the mpg too.