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2005 38 lightning low top speed.
Hello. New owner to a 2005 38 lightning with 525 efi bravo Xr semi stagered. Im not pleased with the topspeed. I get 75mph 79mph one time. Testreport says 93mph. I get 5000rpm on Stb engine and 5300 on port. Drive setting 4or 5 on indicators. I have bravo 32p. Props. What at are your ideas? Anyone with same boat? Top speed? Looking forward to hear from you |
Are you running the same props that came from the factory? (The ones indicated on the performance report) Are you sure the test report says 93? That sounds a little on the optimistic side, maybe 83 but not 93.
Factory top speed is with no gear, barely any fuel, one person, but you should be closer to it than you are indicating. Check for accuracy in your drive/trim setup and duplicate what the report says to get a baseline. |
Test report says 93mph. I also think it’s to good to be tru but that is what it says. I have ave the same props that the boat came with. Props looks good but I don’t know if they are good. Thinking of testing another prop kit. Is bravo one props the right way to go or can you or some one else recommend another prop? |
My 02 38' semistagger w/575's did 93 with Bravo 32's
I think 525's did 89 If you're full stagger it should be faster. Props turn in? Should be Drives toed in? 1/8" is good Sharp skeg, no burs Verify trim and tab indicators are correct. Lacking RPM on one engine could be prop bigger and/or cupped more than other side. Or, that drive is not trimming out as much. More RPM on one engine could be trimmed out further, prop that's smaller, and/or cavitating. Make sure drives don't have slop from one to the other Check base timing, fuel pressure. Lay off the meatballs |
Knew a guy that had a bone stock 525HP - 38 semi-stag with 5 blade hydros that ran low 90s in summer heat all day. You have something else going on.
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Originally Posted by keegan
(Post 4637394)
Knew a guy that had a bone stock 525HP - 38 semi-stag with 5 blade hydros that ran low 90s in summer heat all day. You have something else going on.
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First thing would be to have the props checked. You need a starting point.
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Maybe 2 different gear ratios in lowers? Happened to me with our 353, bought a replacement new XR 1,50 drive from a local dealer and instantly RPM was off, was told it needed breaking in. Boat top speed suffered and boat listed a bit. On the 3rd return to dealer they replaced the lower with a proper 1.50 and all was good.
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Anyone knows the right gear ratio for a 38 with 525? |
1.5. |
This evening I have checked ratio and I have 1,50. Also messured Toe in and that the trim indicator is synchronized between starboard and port. next thing will be to try another prop kit. |
something is wrong with starboard engine port engine is carrying it
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Originally Posted by 47 lightning
(Post 4638060)
something is wrong with starboard engine port engine is carrying it
Mayby compresson and leakdown test on that tomorrow |
I had the exact same boat with exact same setup. Ran 88 all day long. The 525's should turn 5300 easy with 32P Bravo 1's. The fact that the starboard is only turning 5000 is definitely an indicator of something wrong. Here's what I'd look at:
- compression / leakdown test - fuel pressure (should be around 40-43 psi) - fuel injectors |
145psi all over plugs looks rich. Injektors was sent away 2 month ago. Only checkd fuel pressure at idle. Was 43 psi at idle. |
valve springs will do it too broken outer big spring will work great till about 3500rpm then valves will start to float because of lack of spring pressure take valve covers off that motor and look for broken outer big springs but before that check if motors run even rpm till about 3300rpm
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Screwed up props will mess with it also. Have them checked. May not be them but the easiest and cheap to have them looked at. |
Have the same boat. Bet your engines are getting tired. My speed is down too along with compression. Should check yours.
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I have 145psi all over. Going to test anorher set of props this or next week. If that doesn’t make any difference. It might be the engines. |
145 psi sounds a little low - my 525s with 200 hours were about 160 cold.
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Ok I try another set of props and some other things otherwise we pull the engines this winter. |
Two thought, check the fuel pressure @ WOT and put a scanner on the engine for fault codes...different props aren't going to get the 300 revs you're missing
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No codes. Not checked fuel pressure at wot yet. |
Update: i have now tried another set of bravo 32p lab props. Now I reached 86mph with halffull fuel and 5 guys onboard 5100rpm on both engines. . With my old bravo 32 I didn’t get her over 80. The other thing is the new kit ventilate and spins a lot when I take it on plane. My old ones did not. |
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