Best Prop pitch
09-09-2003, 10:32 AM
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Best Prop pitch
I'm running a 1982 formula 302 LS BBC/ TRS ( approx 420 hp.) set up much like Jon's. Currently I'm running 25 pitch Mirage plus and can't seem to get more than 4100 rpm and 60 Mph out of the boat. Am I running the wrong prop. Any thoughts. Thanks Rick G.
09-10-2003, 01:51 AM
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That sounds like too much prop, you should be in the WOT range for the engines at WOT. I'n not sure on the WOT range for the 420's, but I'd guess it's something like 4400-5000. it's hard on the engines when they're propped to spin below the recommended WOT rpms.
09-10-2003, 03:57 PM
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Rick G
I owned an 81' 302 with aprox. the same power. I ran 23p mirage 3 blades on it. They worked very well. I could spin the motors 5000 rpm and the boat did very close to 70 mph. I know that the prop selection these days have come a long way but it sounds to me like you need to down size your pitch. I have an 86' 311 with Kamma surface drives that does the same speed as my old 302. I've been told that to older style hulls are a little faster than the euro style that started in 86' The 302's would suprise you because its faster than it looks.
anyway, good luck.
Perfectmix, Josh
I owned an 81' 302 with aprox. the same power. I ran 23p mirage 3 blades on it. They worked very well. I could spin the motors 5000 rpm and the boat did very close to 70 mph. I know that the prop selection these days have come a long way but it sounds to me like you need to down size your pitch. I have an 86' 311 with Kamma surface drives that does the same speed as my old 302. I've been told that to older style hulls are a little faster than the euro style that started in 86' The 302's would suprise you because its faster than it looks.
anyway, good luck.
Perfectmix, Josh
