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Quote:

Originally Posted by WAYNOFZR (Post 2217954)

Hook-up/repair Tab and Drive Indicators
External Steering

If you are already in the mid 70's and looking for 80, you might want to move this up to #1 on your priority list.

my 91 bullet 600hp normaly aspirated 26 bravos 1 & std. bravo drives tops out at 83 at 5600 rpm need alot of 380 tabs to overcome porpoising. a friend is loaning me a pair of 30 3blade let you know what hapens.

My 88 Bullet has 454 bored 30 over, edelbrock air gap manifolds, 750 holleys, gil exhaust, trs drives and 4 blade hydromotive props. I trim my drives to only 3-4 on the indicator and only see 60mph on the GPS. Should I trim them out farther?

I'm sure someone else will pony up here since I've got no indicators. You need to give some more info. Pitch on props and RPM's, etc.

Like I said earlier at lunch Wayne... we need to go through the tune and make sure she's right, then play around and see what's up! I think there's a few MPH left in her the way she sits.

Some labbed pros would probably help her bite more, too.

Quote:

Originally Posted by WAYNOFZR (Post 2216049)

Since there has been a recent flurry of Bullet threads, I thought I'd throw one out. On the long list of things to do on my boat, one of the items are looking at some different props sometime this year. The current ones are not in the best shape (dinged, not by me)

Boat info is:
1988 Bullet with NO transom notch
Bravos with 27P 3 blade Mirages
454's with B&M 250 chargers (single carb)
Mechanics guessing have told me engines are around 550hp (not dynoed)
Runs about 6 lbs boost at WOT
WOT is about 5000 rpms with these props

Performance:
props blow out at anything over about 1/2 throttle getting on plane (not really a problem)
Hard turns can blow out props if trimmed up any
Boat wants to porpoise slightly at speeds above 65mph
Top speed is only about 71 on GPS (with 1/2 fuel and 3 guys)which seems too low. I was expecting at least 5mph more and was hoping to see 80.

Am I overly optimistic with what I expect speed to be? Should I go to a 4 blade? Thanks to anyone with advice.

my '88 notched transom trs. 500 bulldog 540, gps 72 smooth water 4b 24bravo 5300. takes somewhere around 625 to run 80. one of kevins ran 85 with 725s. i redid my motors might gps tom. 28 4blade bravo.

28 4blade bravo 5000 77.2 gps

5050, can you give me your engine details? Was it dynoed? I would be happy to see that kind of speed out of mine. Do you know what you cruise at around 3500 to 4000rpm? Like Tom said, we still need to play around with it. I'm lucky to know 3 good mechanics that are friends :)

Quote:

Originally Posted by WAYNOFZR (Post 2332991)

540s j&e flat top pistons, eagle crank & rods, dart intake, demon 1090 carb, comp. custom grind hyd. roller .648 .648 254 262 duration @.050 110 lobe separation with 4 degrees of advance. chineses aluminum procomp heads. crane roller rockers. cmi dry exhaust.

i might have 1 or 2 mph left in it still runin way rich at idle if anyone could help with that i would appreciate it & would a 29 3blade give me anymore rpm and speed?:D

Quote:

Originally Posted by 5050 (Post 2333013)

Maybe you just need to go out on a more windy day.:cool-smiley-027: lol! What did those motors dyno?