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View Full Version : Max RPM stock 330?


ZekesterbluH3
09-02-2008, 09:16 PM
I'm running an '87 Hornet 3 withe 330, thrua Borg warner, thru a TRS, mirage 27...What's the max RPM I can run this engine for sustained runs?
mrfixxall
09-02-2008, 09:26 PM
4400 to 4600 rpm:)
ZekesterbluH3
09-02-2008, 10:20 PM
rut roe....I better get a different prop....
f_inscreenname
09-02-2008, 10:29 PM
You can do up to 5 grand but only for short bursts.
rr1048
09-02-2008, 10:43 PM
From your comments it sound like you are turning too much. What are you currently turning? I have a 20' Cigarette with a TRS and HP425 and I can only spin a 27 Mirage + 5000, I generally run a Mirage 25 at 5400. If you are spinning near the 5000 number you might want to check your tach for accuracy.
Good luck
ZekesterbluH3
09-02-2008, 10:43 PM
shouldn't I prop to only hit the 4800?
mrfixxall
09-02-2008, 11:03 PM
shouldn't I prop to only hit the 4800?

you can wing it to what ever you want! but with the cast internals like the pistons have will in time shatter,crack a piston skirt ect so to be on the safe side 4600 max and throttle down when you leave the water..:) lets see a pic of your engine (pic of the front of the intake),you may havemore hp then you think..
f_inscreenname
09-02-2008, 11:06 PM
My original valve covers for 1986 MIE340 stated 4200 to 4400 WOT if you want to stay to factory spec's.
ZekesterbluH3
09-03-2008, 08:53 AM
From your comments it sound like you are turning too much. What are you currently turning? I have a 20' Cigarette with a TRS and HP425 and I can only spin a 27 Mirage + 5000, I generally run a Mirage 25 at 5400. If you are spinning near the 5000 number you might want to check your tach for accuracy.
Good luck

When the boat was last in the water, 9 years ago, it ran above 55 mph at WOT turning 5000, I had it out on flat water on the weekend, 51 on GPS at 4800, bottom paint is in really poor condition, It has been run at 5100-5200 for short bursts, I will have alook at the intake as mentioned, but I think it is a stock 330 Merc....

I'll look into the tach,
BigGrizzly
09-03-2008, 07:25 PM
Let me save you time that boat will maybe turn q 23 pich if it is stock on a good day and won't over rev it.
BUIZILLA
09-03-2008, 07:33 PM
23 Mirage or a 22 Turbo I
ZekesterbluH3
09-03-2008, 08:07 PM
what speed do you think i can pull with that prop?
BigGrizzly
09-04-2008, 12:15 PM
I will guess from my experience and that would be about 61 mph. on a good day.
VetteLT193
09-04-2008, 03:27 PM
When the boat was last in the water, 9 years ago, it ran above 55 mph at WOT turning 5000, I had it out on flat water on the weekend, 51 on GPS at 4800, bottom paint is in really poor condition, It has been run at 5100-5200 for short bursts, I will have alook at the intake as mentioned, but I think it is a stock 330 Merc....

I'll look into the tach,

are you sure you have a 27 on there?
BigGrizzly
09-04-2008, 03:32 PM
Sounds like a 21, or smaller. I was thinking a classic with my numbers, the Hornet 3 is about 4 to 6 mph slower then a classic and should turn a snaller prop by about 2 inches.
ZekesterbluH3
09-04-2008, 03:58 PM
are you sure you have a 27 on there?


aww so sorry, yes I'm a moron, didn't spell check..it's a 21P, sorry to get everyone scratching their heads...so now it makes sense why I'm pulling the 5100-5200? I should try the 23P?
mrfixxall
09-04-2008, 04:34 PM
I would go with a 23 or 25 turbo 1,need those pics!!! that heavy boat and 5100 + rpm dont make sence..you may even have a 420 merc..
ZekesterbluH3
09-04-2008, 04:49 PM
I would go with a 23 or 25 turbo 1,need those pics!!! that heavy boat and 5100 + rpm dont make sence..you may even have a 420 merc..


smiling, I looked at it, couldn't see anything but the 330 stickers...I will get pics when I can, also will check tach.....