Bullet prop question
#11
#13
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?
#15
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.
Some labbed pros would probably help her bite more, too.
#16
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Joined: Oct 2007
Posts: 609
Likes: 11
From: Tulsa oklahoma
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.
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.
Last edited by 5050; 11-11-2007 at 07:08 PM.
#18
Thread Starter
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Joined: Nov 2006
Posts: 714
Likes: 4
From: Va Beach, VA
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
#19
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Joined: Oct 2007
Posts: 609
Likes: 11
From: Tulsa oklahoma
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 

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?
#20
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?
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?

lol! What did those motors dyno?




