Just like everything else, the answer depends on what you're looking for. I run a T-67 and find that it's got more than enough on the top-end to blow my stock block. The larger the turbo, the greater the lag for the most part. A T-67 is good enough for 500+ horsepower. A T-76 is probably good for 700+. It depends if you're actually looking to make that much power. For a daily-driver you might be happier with the smaller turbo.
I'd give the same comment about the BBK SSI. I get into back-and-forth conversations on the forums all the time about whether breathing mods make any sense with a turbo. It's a beautiful manifold, I'm sure it would add a few horses naturally aspirated. But does it really make sense to increase breathing efficiency when you're pumping in huge amounts of compressed air? Do the flow-characteristics of the manifold change with compression? Does it make sense to spend hundreds for an incremental gain in efficiency when you can increase the engine's relative volumetric efficiency with a little extra compression? Not to me, unless you're going for maximum possible horsepower and efficiency. My QH already tells me I'm running at 160% load, do I really need better breathing?
I'd say also if you're running a stock block, you can easily overwhelm it to the point of splitting with a T70 and no other breathing mods. Just my 2cents.
Anyways, about the injectors, once again, size them for the horsepower you're looking to make. I run 36lb. injectors, good for 400 or so horses I've heard. At that point you'll want a high-flowing fuel pump and likely an MAF with a higher flow-rating. The bigger the injector, the crappier the idle.
Really it's the same conversation from 20 years ago - should I run a 700cfm or 800cfm carb, and what size jets should I use? The only proper answer is "it depends."
I'd give the same comment about the BBK SSI. I get into back-and-forth conversations on the forums all the time about whether breathing mods make any sense with a turbo. It's a beautiful manifold, I'm sure it would add a few horses naturally aspirated. But does it really make sense to increase breathing efficiency when you're pumping in huge amounts of compressed air? Do the flow-characteristics of the manifold change with compression? Does it make sense to spend hundreds for an incremental gain in efficiency when you can increase the engine's relative volumetric efficiency with a little extra compression? Not to me, unless you're going for maximum possible horsepower and efficiency. My QH already tells me I'm running at 160% load, do I really need better breathing?
I'd say also if you're running a stock block, you can easily overwhelm it to the point of splitting with a T70 and no other breathing mods. Just my 2cents.
Anyways, about the injectors, once again, size them for the horsepower you're looking to make. I run 36lb. injectors, good for 400 or so horses I've heard. At that point you'll want a high-flowing fuel pump and likely an MAF with a higher flow-rating. The bigger the injector, the crappier the idle.
Really it's the same conversation from 20 years ago - should I run a 700cfm or 800cfm carb, and what size jets should I use? The only proper answer is "it depends."
