I was wondering if a motor can be "tuned" to put out more hp as a factory motor (no HT parts)? What I mean is if a 250 hpdi motor dyno's at lets say 245 hp, can anything be done to that motor to get it closer to the upper end window of the 10% rule...say 270-275?
have it blue printed ht can do that too.
Never heard of blueprinting...what does it involve?
dissasembling motor and making all the ports matched ports tollerances are sized exactly the same as it was intened to at the factory to true factory specs. but the factory pulls it out of the casting and asembles it its close but not buleprinted
Hydro tec also has a dyno they could dyno before blueprint and after and do a dyno tune on your motor to get it "dialed in" to perfection.
Ya, I wished they would have assembled it that wayRunning @ 1500 ft elevation with a zx250 HPDI 250 25T1 I only turn 5400/5500 rpms loaded (full fuel, full tackle, two people, empty livewells). GPS speed is only about 67-68. I don't understand how so many others are able to have the same load and turn 5800-6000 rpms. Heck even at 400 ft elevation I only turn about 100 more rpms. Tried different props, different plate heights etc. The ONLY thing that seems to make a difference is if I have a 1/4 tank of fuel or less left, then the rpms come up to 5600-5700. I guess the tach could be off? Speed is same and it would make slip percentage even worse! GRRRRRRR!
I know what your going though also, I was only turning 5500 but I change the plugs and fuel water filter in the boat and got 100 more r's on my home lake
If I run my boat out of gas .25 tanks or less I can see 5700 for 1 sec with the j/p all the way up but its more like 5500-5600 with gas in it
mine is going on a dyno on oct 6th as soon as I get back from Mead
What kind of speed are you getting?
70.5 is close to the best that I have seen, my boat runs at 69 most the time
got a 250 and cann't even see 72 every day, I'm less then pleased to say
Modified by macinckirk at 6:47 PM 9/26/2008
Modified by macinckirk at 1:23 AM 9/27/2008
Ya man...sorry to hear that. My boat will run 75 DOWN river @ Havasu. Lucky if I see 70 there on the main lake. Personally I think these posted speeds on BBC are BS but whatever. I would have like to have seen atleast the same as my zx225/3.1 225 did on Havasu with my zx250.
how bad does your boat drink gas??? Mine is unreal
I think were running about the same speeds, I think I'll see 73-74 on mead but that will be with just me, no partner and that will be on the run back Down
Now don't get me wrong I love my boat, just need to get some mire speed/r's out of it
I'll let you know what I find out after it gets put on the dyno
I'm running a 2004 ZX250 with a 26p TXP 3 blade at 1 1/2" below pad and 73-75 mph GPS @5800 rpm's. The boat came with a 27T1 prop but this prop is balanced and blueprinted with PVS holes added by Mark Croxton. AWESOME prop for my boat.
My boat is ok on fuel. I noticed the HPDI at WOT isn't much better than the old 3.1 Vmax. The HUGE difference is between 3-4 thousand and it's pretty good to under 5 grand. Oil usage is no problem even with the update.
I just feel something is not right with this engine...I've owned enough to know but I can't put my finger on it.
As you, I love this boat. I don't think I'm unrealistic to expect 5800 rpms @ 72.5 GPS with a full load, gear and partner. My zx225/VMax 225 did this no problem. I bet our engines are low on the HP side but within 10%. Maybe they will hold together longer...ha ha!
At 1 1/2 inches below pad I couldn't make a high speed turn to save my life! There must be some serious cup to that prop. How did that boat run with the 27T1? I was only able to turn 5200 rpms with mine.
Well 5 keepers here is the deal
my motor just came off the dyno and it is turning 5700-5800 but right at 5780 at sea thats why I only see 5800 on my tach for a sec oh my tach is a dig just so you know
on mead at 1000 above sea I could only see the 5800 for 1 or 2 secs with the B&B 25t-1 from mark the best speed I seen was 73.38 gps I think running UP river in the morning, full tanks of gas and just me
My tech shows 70 hrs on it but the motor has 74 hrs on it and has hit the rev limiter at 6100 14 times, so it had to be form the 1st owner and whatever prop he was running and I know it was not the 25t-1 I think he was running a 25 tem
They say my motor is right were it should be and nothing they can do for me, this is a 5 star yammie dealer and does not sell skeeters, hel* there is no skeeter dealers around here any more
So when its all said and done I have a 70 mph boat when I have 2 guys and a full trny load in it
Thanks for the info. Have you tried a 25 Tempest to see if you gain rpms and speed? I think your boat is faster than mine and it weighs more! LOL.
that boat should be faster than that.
That's why I'm looking for help without spending an arm and a leg!
had an 05 zx250 but I had a 300 and that thing ran. didn't have a gps but it ran great. now I have an 06 21i with a 300 and by myself this one gps @ 79.9. with me 220 and my partner 260, 50 degree water and air, gps at 77.8 at Lake of the Ozarks. it took some time to get the plate correct but when I found it I am very impressed. my partner had a zx250 with a 250. boat would run 80 with those old props, threw ears though. balance and blueprint your prop and you'll gain your cheapest speed. good luck.
I may have to go that route with a B&B. If not that doesn't work, I give up!
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