"I'm mixed on this. If I had a stock TB and a LS1 intake, I would buy a BBK for sure. Unless I found a LS6 intake cheap, like $250 that dosnt happen much. Most are $330-350. A BBK 85mm intake is only $399 at NewEra were I got mine. So thats a good deal if you have a LS1 intake still, its 5whp more then a LS6, that like 25% the power gain for not alot more money.
And you can port them pretty easy, maybe even fit a used 90mm TB on them. But Ive found most 346s are fine with a 85MM TB. The BBK is really nice compaired to that Profenial Products intake, Ive worked with 2 of them, and there were both junk. That heat soak stuff is BS, after the dyno pull I could push my hand hard on the BBK and keep it there. Warm not hot, just the same as my LS6 gets. The heads were to hot to touch. Sitting in a parking lot in the sun running it will geat hot, but so dose the wheel wells and everything else from engine heat and no airfolw. The intake sits on the rubber Orings, its not bolted right to the motor touching with a paper gasket. The bolts carry some heat but this is a must.
If I had a LS6 intake and a ported stock TB I don't think I'd buy a BBK, but then agian it was amost have the gains of the fast over the really good LS6 intake with a 75mm TB. And I could, and I'm going to sell my LS6 for 330-350$ and my ported stock TB for $100.
The fast intake is a lot of money all setup on your car, I was hoping to make 420whp and was disapointed on the 415whp. But even Mike at new era said he sees a lot of cars that don't gain 13-15whp over a LS6, and with tunning only gaina 9-11 kinda sucks for the money. But its true if you have stock heads, and cubes. But I've seen cars gain 25-30 with smaller 370-383cube deals, and good heads, over the LS6. This was a lot of work and time, thanks to mike at newera for letting me use the dyno doing all this, and keeping all these parts around the shop. And my roomate for helping me change all these parts late at night. I'm hoping to go 124-125 and a 10.99 is the better fall air."