- Jan 12, 2010
not mine-its a 99 rock solid reliablity.
There's no way to flow more air without flowing more fuel?I don't want to be rude but you're talking in circles. Engines are nothing but air pumps and the more air you pump the more power you get. If you don't want to improve air flow with porting and polishing the heads or changing the lift and duration of the camshaft AND putting a high flow header system and extractor on the engine and you don't want to increase fuel flow which would definitely be dictated by the greater air flow then what specifically do you want to change? There is no free lunch.
I believe there have been some industrial air compressors based on the GMC V6 (the old big block) where one bank was a regular engine, the other bank was used as an air pump. So yes, engine can flow quite a bit of air… but as you might guess, it was half-down on power.There's no way to flow more air without flowing more fuel?
I do shorty headders now instead of long tube. Like you posted, the sbc light weight head castings are garbage and not worth putting $$ into.I threw out an absurd suggestion for the exhaust manifolds. Me? I would rebuild the 350 and get some Vortex heads or something good.
I believe there have been some industrial air compressors based on the GMC V6 (the old big block) where one bank was a regular engine, the other bank was used as an air pump. So yes, engine can flow quite a bit of air… but as you might guess, it was half-down on power.
It’s a bit of a saying, really, that an engine is an air pump. Ignoring when gasoline is pumped to and through the injection system, the rest of it is dealing with gasses, not lquids. And once gas is mixed with air, it’s a gaseous substance too, following those laws of physics. And in the end, it’s the combustion of that gasoline-air mixture that releases energy, which you are after. Get more of that air-fuel mixture in and out of the engine, roughly speaking, and the more power you have. The more “air” you pump, the more power you have. Ergo, calling it an air pump.
For gasoline to combust properly, the vaporized gasoline molecules have to be close enough to each other that it burns quickly (not too lean). But to burn ”good” you have to have enough air to support that (not too rich). Chemists can figure out the ratio, based on the chemical reactions, but IIRC air-fuel winds up being stuck between about 10:1 and 16:1, with 10:1 being too rich (down on power) and 16:1 likely causing other issues, and on the verge of not running either. 12:1 was rich max power, and 14.7:1 was “best” for complete combustion. Something like that. My learning was back with PFI was new stuff, so maybe DI can eek out a bit leaner, not sure, but lean mixtures are not powerful mixtures (less chemical energy into the engine = less mechanical energy out).
[Note, diesels are different and run vastly leaner.]
Depends on the ECU and what it allows. General case, I'd expect for it to accommodate. The older it is, the more likely it wouldn't toss a code I'd think. But the newer the engine, the less likely this would matter: last 20 years or whatever, the OEM's have been doing what they can to eek out the numbers, as shoppers are paying attention, and I don't think OEM's are leaving much on the table. Maybe on the intake side, for noise reduction, same on exhaust--but not in the cylinder head nor intake manifold. You might get a pinch from intake restriction removal (not necessarily "cold air intake") and maybe something from a catback, but I'm not sure there's piles there.What if you take a completely stock engine and then just add headers and port match the cylinder head ports to the intake manifold ports; would the engine computer add more fuel?
There are cases where a 6.0L will get better MPG than a 5.3L all things being equal.....Most 1500 pickups that came factory with a 6.0L are AWD, So you can't compare what it gets to a 2wd 5.3L pickup. And you definitely can't compare a 2500 to a 1500 in regards to fuel economy.
The 6.0L/6L90E in my 2000 Silverado 1500 seems to do really well.....Though I'm not one to calculate fuel economy. But it does accelerate effortlessly.
My dad has a 2003 Tahoe with a LQ4 6.0L swapped in place of the LM7 5.3L.....No difference in fuel economy that we can tell, Again.....A lot more pleasant to drive with the extra torque under the curve.
Stock 6.2L LS3's are very docile with just as smooth or smoother idle than any 5.3L