The 454r, with some mild plenumn work, will work good. I am sure the Sniper Jr will work well also, haven't used one yet, as, they are hard to get right now. Probably won;t be that much better, but possibly. I would say, that, un-touched, vs untouched, the sniper will have a small edge. If you do the minor plenumn porting, it will be even.
For methanol, on a 511, turning 7400+ I would even consider the Super Victor. Its generaly to big for that cubic inch, but, with methanol, will definately help. On the dyno, on gas, they will make a bit more hp, but the car will run slower at the track, in that cid range, unless your really winging it about 8000. With methanol, it makes so much more tq, plus the extra volume in the intake helps, due to the fact your running nearly twice as much fuel, so, that fuel, needs more room.
Frank
Advanced Performance
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