Formula 242 with high x-Dim.
#1
Thread Starter
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Joined: Apr 2021
Posts: 101
Likes: 37
From: Germany
Hey Guys,
Bought this boat and did a complete refit. Boat was without power and now its powered by a 502 MAG MPI with stainless manifolds. X-Dim is about 1.5 inch higher as original. Bravo1 drive, 1.5 Ratio.
This was the first test. I have now a Revoloution 4 23p Prop on it.
Boat accellerates and gets on plane perfectly.
2800rpm - 32 mph
3300rpm - 40 mph
3900rpm - 47mph
4300rpm - 55mph --> this is highest speed
This is trimmed ALL THE WAY DOWN. If i start trim her up, i get a massive rooster tail but the boat slows down. I can trim her up to 4800 rpm and she gets 50mph. Feels like the bow does not lift at trim.
Boat has no tabs, driven on a river in fresh water, no chop.
Any suggestions how to improve?
Thanks!
Bought this boat and did a complete refit. Boat was without power and now its powered by a 502 MAG MPI with stainless manifolds. X-Dim is about 1.5 inch higher as original. Bravo1 drive, 1.5 Ratio.
This was the first test. I have now a Revoloution 4 23p Prop on it.
Boat accellerates and gets on plane perfectly.
2800rpm - 32 mph
3300rpm - 40 mph
3900rpm - 47mph
4300rpm - 55mph --> this is highest speed
This is trimmed ALL THE WAY DOWN. If i start trim her up, i get a massive rooster tail but the boat slows down. I can trim her up to 4800 rpm and she gets 50mph. Feels like the bow does not lift at trim.
Boat has no tabs, driven on a river in fresh water, no chop.
Any suggestions how to improve?
Thanks!
#2
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Joined: Nov 2004
Posts: 14,117
Likes: 3,696
From: On A Dirt Floor
Disclaimer: ibknow nothing about those boats with a higher x than stock.
That said, round table talking….
That prop has a listed diameter of 14.6” diameter. Pretty small for a 502 equipped boat.
The Bravo 22 and 24 have a listed diameter of 15.3”.
Therefore, i’d try (borrow/rent/etc) a Bravo and go from there if need be.
That said, round table talking….
That prop has a listed diameter of 14.6” diameter. Pretty small for a 502 equipped boat.
The Bravo 22 and 24 have a listed diameter of 15.3”.
Therefore, i’d try (borrow/rent/etc) a Bravo and go from there if need be.
#7
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Joined: Apr 2021
Posts: 101
Likes: 37
From: Germany
I would have to measure where it actually is. this boat is full V.
I tried 24 pitch bravo1 yesterday, it only went 45 Mph @ 4000rpm.
Then i tried Mirage 23, went 45Mph @ 4100 Rpm
I can trim them up to 4800 Rpm and massive Rooster tail but she never gets faster.
With the 24 Bravo1 i had a feeling the bow was mor up as with revolution and mirage.
Rpms are too low i think. I could try now bravo 22 or mirage 21, but i'm not sure this 502 engine should turn a 23 mirage without problems?
Maybe the motor is low on power?
I tried 24 pitch bravo1 yesterday, it only went 45 Mph @ 4000rpm.
Then i tried Mirage 23, went 45Mph @ 4100 Rpm
I can trim them up to 4800 Rpm and massive Rooster tail but she never gets faster.
With the 24 Bravo1 i had a feeling the bow was mor up as with revolution and mirage.
Rpms are too low i think. I could try now bravo 22 or mirage 21, but i'm not sure this 502 engine should turn a 23 mirage without problems?
Maybe the motor is low on power?





