What makes an LS better than a small block?

[olds307 and 403]

One advantage over the older engines is fuel economy and not just the efi either. The Gen is much better in that department as well. I know quite a few long times Olds guys went LS on this site for that reason alone. One was a carbed conversion and he gained a lot in that department, rest of the drive train stayed the same. They didn't switch to the sbc because it offered no advantage other than cheaper and more numerous parts. My 94 Z71 with a 76 Olds 350, stock 307 heads, A4 intake, 204/214 cam, around 8.5 to 1 compression, factory 454 TBI adapter, shorty Sanderson headers, 307 CCC distributor, timing around 20 degrees advanced, 4L60E and big LT265/75R16 tires would plain beat the similar LS powered trucks idle to 4500 rpm, over that then I lost big time. The LS trucks actually ran a shorter tire and more of a gearing advantage. When I had the 454 TBI and it ran right, sensor and throttle shaft issues, it would plain embrass them off the line. The one place the LS trucks one is fuel mileage buy a good margin. I got 16 at best, at least 4 mpg less. With a custom tune, I could have pulled within a few but then again a similar intake and exhaust improvement on that era of LS truck would have helped mileage and power, keeping the mileage gap.

 

[pontiacgp]

debates over which engines are better will never end, we will all choose what we like or what's available at your budget.

 

[olds307 and 403]

debates over which engines are better will never end, we will all choose what we like or what's available at your budget.

I agree 100%, only way I will go LS is in a new car, best of both worlds. The LS does have advantages over the older platforms. Otherwise diehard Olds guys wouldn't have switched over.

 

[Matthew Goeke]

ECU tuning, and alot of potential

 

[pontiacgp]

which LS engine is being referred to cause there is a bunch in that family and they are all different with different price tags...in the cars there is the 5.3L, 5.7L, 6.0L, 6.2L and 7.0L and then there is the LSX 454

 

[L92 OLDS]

I agree 100%, only way I will go LS is in a new car, best of both worlds. The LS does have advantages over the older platforms. Otherwise diehard Olds guys wouldn't have switched over.

I'm one of those guys that has flown the Oldsmobile flag since a teen and switched to LS power. Keep your car all GM!

 

[LukeZ]

LukeZ, something must be off about your 305, as mine gets over 20 mpgs with an aftermarket cam.

Guess it needs a tune then? I'm not exactly on the pit crew at NASCAR... If I were to get a air/fuel ratio gauge like one member suggested way back in this thread, where would the sensor be installed? And how would I know what is the best ratio for my car? The engine is 100% stock, with the exception new of exhaust and a Performer Air Gap that'll be going in around the end of March when I get home for spring break. I thought 14.7:1 (air/fuel) is close to what it should be? Would leaning that out get better mileage, or do I risk tearing the engine up and being horribly underpowered?

Sorry this is unrelated to the original question. We're all snowed in and bored, right? 😉

 

[LukeZ]

And I'm about to make myself seem like an idiot but that's okay.

What is the difference between TBI, TPI, and EFI (Did I leave any other common ones out?)? Throttle body, tuned port, and electronic fuel injection, respectively. Which one is fuel injection directly into the cylinders? Which one is the one that pretty much looks like a carburetor?

Best option for a Gen I (taking into account total cost, gas mileage, and power)?

 

[CWPottenger]

And I'm about to make myself seem like an idiot but that's okay.

What is the difference between TBI, TPI, and EFI (Did I leave any other common ones out?)? Throttle body, tuned port, and electronic fuel injection, respectively. Which one is fuel injection directly into the cylinders? Which one is the one that pretty much looks like a carburetor?

Best option for a Gen I (taking into account total cost, gas mileage, and power)?

Basically EFI is the overall general description of Electronic fuel injection.
TBI is Throttle Body Injection which is like a carburetor in that it is a wet intake system( fuel and air in the Intake) only difference is TBI fuel is electronically controlled and either added above or below the throttle blades depending on style and not dependent on venturi air flow. Carburetor fuel is controlled by jet sizes and needle valves and is dependent on venturi air flow for proper function.
TPI is Tuned Port Infection which is a dry intake system( only air in intake fuel is injected directly into each cylinder) Within that group there are various forms of injection styles on how the injectors fire as a group or individual.

If you are dealing with a Gen 1 SBC then TBI is the easiest in that no changes are required to the actual engine. Remove the Carb, add the ECU and upgrade the fuel system and you are done.
TPI requires intake changes and sometimes accessory changes, possible valve cover changes and/or intake spacers as well to clear everything. Still add a ECU and upgrade fuel system.
Both systems are well supported in the aftermarket world as complete systems or factory piece tuning. Cost is comparable either way nowadays.

 

[pagrunt]

This reminds me about the old big block/small block debates when I was a kid. I would say the best one is always the one under your hood as I was told by the old timers that I learned everything from. Each has their pro's & con's. After having one failed variable lifter in the 5.3 in my Silverado take the whole engine out last year I will accept the neither is perfect.