E-TEC beats out Verado?

[INXS]

npartin, so it's ture that if you have the right propping the yammie 300 may be close to a Merc 300X ? Maybe within 2 mphs? BTW, hows the skiing at Bachelor this year, you have any good snow? Great countryside, as long as the South Sister doesn't blow its top! I heard it has a buldge build up in the last year or so!

[150aintenuff]

it would be closer to the 250XS than the 300x because the 300x is closer to 335hp than 300... the 300 hpdi is closer to older 300 (pre x motor) in hp Right propping is key regardless of HP so yes you could get close but dont expect a consumer motor to run with a performance motor of about 30 hp more. Batchlor is lackluster on snow so far but that will change, hood is open but with small base. Sisters are fairly quiet... it is MT ST HELENS that is making the news noadays.

I would assume that if your options were a 250 merc, 250 yami 250XS merc 300 yami and 300X speed would be as follows... 250 merc 250 yami (with in 1 mph) 250 XS 300 yami (again with in a few MPH ) and on top by maybe 3-4 MPH 300x total variation would be maybe 5-6 MPH total between 250-300X as merc 250XS was around 270 on dyno 300X is somewhere between 330-335HP 300 yami is sonewhere between 290-310 hp 250 XB was if i remember right 265-270 hp and 250 EFI was around 270 as well.


what is the 300 going on...big offshore boat or light fast boat.... also 300 hpdi is 100 lbs heavier than 300X

[150aintenuff]

oh yea the 300 hpdi would be a little cleaner on fuel and if you ever made it to california you could use it at tahoe whaere as 300x you cannot , it also may use less fuel crusing around at lower rpms as well. but on big end 300hp worth of fuel is 300 hp worth of fuel so on top they use about the same. but I would assume that DFI would use less in part throttle aplications but could be wrong, having never had a chance to run either engine, Have ran 250 HPDI vmax though and it was strong i thought for 250 hp so weigh the options as the 300 is just turned up 250...

[INXS]

I'm thinking of going for the 24' Progression, it's motor has been sold, and wanted to check on the out-puts (top speeds) on the motors. The 300X is allot more $$$ that's why I was wondering about the yammies. I'll give it some good thaught as I really like my Starflite but also like the Progression.
Thanks for the info.

[blkmtrfan]

I'm thinking of going for the 24' Progression, it's motor has been sold, and wanted to check on the out-puts (top speeds) on the motors.

Which one are you looking at INXS?

[150aintenuff]

hes lookin at 300 yami compared to X mota

[blkmtrfan]

I meant which 24 progression was he looking at

[150aintenuff]

my bad oops

[blkmtrfan]

No problem


Now I just want to know what INXS has to say

[INXS]

I meant which 24 progression was he looking at

http://forums.screamandfly.com/forum...t=63047&page=1

[blkmtrfan]

INXS mragu's boat looks very nice in the pics, very cool

[JWTjr.]

As I stated on another post, we have not seen a 300x produce anywhere near 330 hp on a propshaft dyno test, nor using the often used and very reliable GPH fuel consumption extrapolation (GPH consumption = approximately 10% of actual horsepower production, i.e. an engine consuming 30 GPH ~300 hp approx.). Best I have seen is a 300x that burned a shade over 30 GPH, indicating 300 hp. In our 300 shootout, the x produced 277 propshaft horsepower and the HPDI produced 275 (both at rated RPM levels, 6200-6800 for the x and 5000-5500 foor the HPDI). These engines produced speeds within 1.8 mph opf each other on the same boat (Gambler 2200) on the same day with the same driver and load.

Yamaha reps did state many times during the test that they would never deny service to anyone spinning one over 5500 (the engine's listed maximum RPM), but they seem to back away from putting that in print.

JWTjr.

[150aintenuff]

Nt to discount dyno
numbers but 277 and 275 hp respectivly seems ALOT low for engines that are supossed to be 300hp AT the Propshaft..... Correct me if Im wrong but didnt Propshaft HP become industry Standard in the late 1980's round about the PROV150 came on the market???? It sounds to me like the ole Numbers game is occuring again.. and I am no edxpert with many dollars worth of equipment but it seems to me that engines in this day and age not meeting the cowling HP or exceeding it wouldnt last long in todays market....

also the lawyers wont let them put it into print.... if it is printed there isnt a way out that the lawyers can use to deny coverages...even if reality says different.

also not to discount numbers again from a DYNO but If 300's only made 275 hp there would be alot closer numbers (less than 2 mph) in MPH to the 250's that are about 270 them selves...(250XS is between 250-270HP) ....unless of course ALL engines are under cowling posted ratings. now im confused , maybe the bible can anser som of my questions...... HMMMMMMMM... guess ill be buying some more toys....


taken DIrectly from MERCURY PERFORMANCE WEB SITE


Specifications
PROPSHAFT RATED HORSEPOWER(HP / kW): 300/224



277 isnt 300... also looking at bigKhuna 300 Comparo I dont see any Dyno ## listed in article......just an observation.

[150aintenuff]

MORE INFO


did some looking around yahamas website and I went back through the articles in a few B&WB mags i have.... like 3 years worth and this is what i have found so far....

acording to JWTjr GPH used is ~10% hp.... welll what about Yahama 225 four stk.. 224hp (B&WB DYNO IN TEXT)(honda/yahama shootout) at 19.5 GPH....... hmmmm NOT 10% more like 8.70%... or 300HPDIat 25.9GPH if HP is 300 like advertised...Hmmm thats 8.6% OR 250 HPDI at 21 GPH HMM thats less than 8.4% fuel usage... not a single engine was near 10% and i am sure mercs , hondas, Suzukis, Nissans, and even EVinRudes are in the same isle all less than 10% seems to me I recall a test of the 225HO on a stratos that only used 19 GPH as a fitch MOTOR... dont take my word for it Yahama Posts Performance data on their website... AS does Suzuki, As Does Honda... need i continue.... In this day and age the rules of old are being changed and if a conventional Carburator uses 10% isnt it safe to say that a performance tuned EFI would use less say 9% and a highly tuned and refined 2stk or 4 stk would use even LESS... and the less fuel is being burnt the less that gets unburnt due to over rich mixture... so if A/F mix is spot on then gee les fuel goes in for more power to comeout..... thats why there are automobiles today that have 345 HP in smallblock displacements that were only conseived as bigblock power 25yrs ago.(HEMI) and will get 20MPG to boot....

[Markus]

npartin, this has been discussed before, and if you dig up the appropriate thread using the search function, I once posted the whole NMMA hp specification + what it is based on.

A summary, if I remember correctly:

1. Engines above 100 hp have 5% leeway from stated horsepower, measured at the prop. shaft at the middle of the max rpm interval

2. Humidity, temperature and pressure when those measurements are made are based on the ISO specification, that goes back to the old German DIN hp spec.

Given 1 and 2:

a) Hp can be a lot higher 500 rpm above the middle of the max rpm interval
b) Hp can be a lot higher or a lot lower depending on the humidity, temperature and pressure when the test was made

Still, it surprises me that the HPDI and 300X are so close in actual power given what has been stated on S&F. It will be very interesting to see the curves in the magazine.