It would also carry a shitload more cost than a carburetor. Worth mentioning because of the budget friendly theme of the whole video.
So basically, that was a stock replacement TBI engine, outfitted with a pair of vortecs, a big flat tappet comp cam, an intake, and a better carb. For truck guys going in a mostly factory application, this doesn't seem all that straight forward or objective, because the TBI trucks have well, TBI's, not 4 barrel vacuum secondary carbs. Anyways, they made a crapton of power with the new setup, but swapping bigger/better parts onto a TBI crate motor and making more power is like falling out of a boat and hitting water.
Look at the numbers:
1st configuration:
235 hp @ 4000 RPM
335 tq @ 3200 RPM
2nd configuration:
365 hp @ 5600 RPM
397 tq @ 4000 RPM
Yes, that's a crapton more output. BUT, it moved wayyyy up the tach, too. In other words, in "stock" form, the engine's powerband was set to peak under normal every day street driving conditions...all power in well before 5000 RPM. Built up, we see the peak torque has increased at 800 RPM, which means you can't utilize the power unless you want to run the engine at 4000 RPM. Same with horsepower...peak moved from 4000 RPM to 5600 RPM, up 1600 RPM on the tach. This illustrates what happens when you increase cam size specs. Is it better? Depends on your application and intended use. May require a looser torque converter or gear/tire change to really use the power in a street-duty truck. The engine in its modified state seems like it would be a nice fit in a lighter vehicle like a muscle or pony car rather than a heavy pickup.
Did you see the electric water pump on the engine? Did you notice that there was no real accessory drive on the front of it at all? This is part of where magazines and TV shows can make numbers on dyno machines that aren't really attainable in the real world.
There are other things to note here, but this seems like enough for now.
The L31 in my Suburban is built up to around 400 ft/#. Worked over factory vortec heads from summit racing with trick springs and retainers (to avoid machine work), ported GM lower intake, GM "Ramjet" or "HT383" or "marine" cam (part number ending "395"), 1.6:1 full roller rockers, mid-length headers, full exhaust, a tune, and a few other goodies. This motor propels my loaded down 6000# 4x4 lifted/big tire Suburban beyond my expectations. I've performed other drivetrain mods to complement the setup, namely a warmer torque converter and taller gears, and this of course improves performance also, but any buildup should be looked at in this manner, as a full combination of logically matched parts, instead of a mish mosh of unmatched stuff. The point being that even with the engine that was built up in the video, it didn't reach 400 horses and the peak of 365 was rated at 5600 RPM, so a bigger cam to make 400 horses would slide the output even further up the tach to likely beyond 6000 RPM, and that's not even doable with the stock intake setup and computer. It seems like I have the L31 in my Suburban built up to close to the performance limitations of the fueling system and computer. I know if I could swap intakes it would make more power. No question. But, if I swapped intakes, I'd probably swap to the ZZ4 cam also, so it's just like anything else you're never done with. How fa$t do you want to go?
