What Cubic Inch 572, 622?
#61
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Big motors are pretty easy to get to idle. They tend to produce a pretty good vacuum signal to the carbs even with large cams. Actually cam selection in many of these motors is limited to valvetrain durability, rather than over camming the motor. It is very easy to over cam a 454 or 502 with a cam that is still pretty mild as far as valvetrain durability. Particularily with hydraulic rollers the lifter limitations can make it very difficult to over cam 600+ motors. Solid rollers are another story!!
#62
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39NAS-T,
Rod to stroke ratio is definately something to consider. Many 572's use 6.5" rods which creates a little concern for an endurance motor, but there are still a lot of motors out there with that rod doing just fine. A better choice is a 6.7" or 6.8" rod with a 4.5" stroke for a rod to stroke ratio close to 454's and 502's.
Rod to stroke ratio is definately something to consider. Many 572's use 6.5" rods which creates a little concern for an endurance motor, but there are still a lot of motors out there with that rod doing just fine. A better choice is a 6.7" or 6.8" rod with a 4.5" stroke for a rod to stroke ratio close to 454's and 502's.
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I'm very happy with my Cobra 750's. They make 740 hp @ 600 ci, single Nickerson 1050. They idle at 750 rpm's and midrange will impress anyone!!! They run cold (120 for water and oil temp will not register on the guage). Boy are they loud with Stelling headers, so I'm trying GGB muffers. If you use Stelling be sure you don't block the stinger water exsit with a exhuast flapper.
I run Max Machine bravo's ... so far great!!!
I run Max Machine bravo's ... so far great!!!
#66
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I think JC Perf hit the nail on the head. Dart 355, AFR 357, and Brodix will be very close in power generation and good choices for the money. More exotic heads like Big Chiefs can make more power for more $$$.
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