Originally Posted by high tech redneck
the car that was supposed to get the 430 went away. the build sheet for that is all in around the same price. big block buicks have their issues as well. these issues to fix would cost about the same. so i'm here researching all of my engine options to see what fits best. thats why 500hp is my mark. i may indeed put the 430 into something like my van or my regal but i like the 4.3, and the 3.8. just for the mpg. out of 3 chioces buick costs alot more. i also live in a climate that is very harsh. not the best for carbs. BBB has big power, but 7.1l will never be good on gas. for 92octane. it costs 1.15+/l. i can literally watch my gas guage go down as i drive. not cool. if i only wanted an engine, it would be a sbc. too bad everyone has one. how many have a 500hp v6?? not as many. how many have a BBB?? but that one is going to cost Big Bucks! the block alone is 5grand, to re work an old block, 3500, hell, the buick paint is triple what ford red is. i'm also dabbling in a rb26dett teritory. i found 1.
rb26dett would be different but nice, if you're talking gas mileage 3.8T may be your best bet. The nissan is going to need to be revved higher for the same torque just below peak cylinder pressure = more tuning to get that mileage. Out of all the options if your truck is going to weigh 3200-3500 or so lbs, a well tuned 3.8T would be the best mileage + 2004r for the lower overdrive. The 3.8 and the nissan will be the most expensive.
Your running 4.3 will take around 350 bhp. 400bhp on a lower mileaged or newer one. 450bhp has been done and ran for a long time, as other people are saying, I'm not trying it though...confused why you want to hit 500hp, there are a lot of guys running 100-150 more torque then their hp numbers with turbo. Machine the block for splayed mains, forged kit, head studs, all the strong pieces. 450bhp could be had safely for a very long life on something like that.
One thing to keep in mind with an evenfire crank is theres a power level that just can't be surpassed. I dunno where it is, do some searches 500hp is nearing the high end of where you want to go with any LU3/LG3 build, it's likely going to come north of 6000rpm which these engines are not designed for = headwork. 450 hp is a lot for an s10 as it'll come with more torque, if you put more effort in the chassis, suspension, and weight reduction than the engine 450hp is all you're ever going to need. There's not that many low 11 second daily drivers to race out there. I'm sure you could get 600hp+ out of a built 4.3 but not for long. Beyond that you may think about an odd fire engine then it gets expensive.
I have a 383 in a g-body with 3.90 gears and th350 I hate watching the gas gauge drop too. I want to swap to something like 3.08 to have some fun on the highway. That sbc from scratch was 3500$ total for every nut and bolt, 500hp, everything new except reworked block. BBB in a regal would be nice, even a stockish buick 430 would be fun with gears.