Made new "OVER SPEED" and "TAND'M LOCK" warning light lenses.
Another question for the ones following the build.
I'm second guessing my decison to build the 250 six. I signed up on an Inline 6 forum and asked those guys what they thought about the plans I had for the engine. They didn't think it would be reliable or streetable at the 350-375 hp range it would take to get the truck into the 13's. It also wouldn't be cheap, especially considering the lowish power it would make if it was detuned to be driveable. I'd be looking at around 275-300 hp for it to be driveable and reliable, and woudn't be enough power to get the truck into the 13's like I want.
The other engine I had thought about was a 4200 Vortec inline 6 that makes 290 hp stock and is all aluminum so it wouldn't weigh much. The drawbacks are, no flywheels are readily avaiable, the T56 won't bolt up, the stock oilpan won't work in the truck, and no cams are available. Other than adding a turbo, there isn't much you can do to add power.
The third option, and the one I'm leaning toward, is an aluminum block 5.3 LS engine destroked to 4.8 using a 4.8 crank with forged rods and pistons. A stock 5.3 is around 310 horsepower. The smaller displacement would get better mileage, the crank would be stronger due to more rod journal overlap, and it woudn't need a radical set of heads to make power at high rpms. I'd like it to make power to 7500 rpm and redline around 8500. I'd use an individual runner intake manifold with four 2-barrel Dellorto carbs (I really like those carbs and IR intakes if you hadn't noticed
) which would make the engine's operating range wider with more average horsepower and torque. The runners are isolated from reversion in other intake tracts so there's a ton more low end torque and driveability. That would be ideal for autocrossing since shifting kills time, and a wider operating range and more average hp/tq would help a ton since it'll be stuck in one gear while making a run. It would be cheaper than building the 250, weigh less, get better mileage, and make a ton more power. A stock 5.3 engine will pick up almost 100 hp just doing a cam and spring swap. Even destroked, it should make atleast 450 hp and be cheaper to build than the 250 six. The drawback is that my current LT1 T56 woudn't work, but it's easy enough to find a LS1 style T56.
Thoughts?