xb2003 which yamaha

[whipper]

If 80 or less I would say no BUT with any Allison she will be a lot better {Lighter} handeling with LWP in my opinion. 2003,s are designed to have higher motor hights to take full advantage of the design asspecialy since your opting for the 150.

 

[Darth VMAX]

IMO A Stock 150 will probably get you mid (maybe upper) 70's. She will sip the gas and run like a sewing machine. What kind of set-back? As mentioned the 2.6L HPDI is hefty for a small-block but should be fine for the XB2003. I would keep the set-back at 6 inches. If you find out you need more you can add the 2" spacers later on. 8" would be the absolute most I could ever see on your XB2003/HPDI. Remember you have a 6150 rev limit and a 2.0 gear ratio.

my .02

 

[bigtis]

put a MECRURY on it:big grin:big grin

 

[Darth VMAX]

Well, if going new MercRury doesn't offer anything to compete with LOL. Sorry, but thats pretty much the facts. sounds to me he is looking for a new motor, not used.

The 175 is the biggest small-block for Merc.

 

[turbo d]

put a MECRURY on it:big grin:big grin

No, I gonna put a Yamaha on her. She is almost home :surprised
I have bought a Yamaha 150hpdi Vmax.
She is temporarily hanging on the Astro.

 

[Lotus 50]

I think the small block HPDI is a good choice.
Both Yamaha and Merc top out at 175 for small blocks now.
I'd go 175XS myself, if I had any money.

 

[baitcaster]

Since the motor issue is mute, I would suggest putting a nose cone on it. Call Titus at Custom Welding. I think he had something to do w/the design on Yammi's nose cones, regardless he does excellent work in my opinion and the low water pick up should add to your overall performance. Additionally, I agree with everything said about Wayne and Matt at HydroTech. Good guys and they know Yammi motors. If you ever want more out of the 150, they definitely could do it.

Have fun and enjoy the ride.

 

[Darth VMAX]

Congrats!

Allisons don't like a buried Lower-Unit. Even if the speeds arent 80+ I would still imagine raising the case would help in handeling.

 

[turbo d]

Finally i got the Allison home!
Big thanks to Bigtis Junior:big grin:big grin

Tomorrow i put the Yamaha on her.
I have the set-back at 6.5 inches.
How high should i start with prop shaft to pat?
Which prop do you recommended me for all a round handling?

 

[K-DAWG XB 2003]

I think you are gonna need more set back. Around 8 inches more. Then, prop shaft height will depend on whether or not you run a LWP.

 

[baitcaster]

Without a nose cone this is somewhat of a mute point. 6.5 inches is not enough to compensate for the need for water pressure and raising the motor up to optimum levels. However most typically start about 1/4 to 1/2 below the pad and work up from there, but I suspect that at 1/4 inch below the pad you will overheat Your Yammi. You may be forced to keep the motor a couple of inches below the pad??????

 

[turbo d]

It is an Allison Jackplate. I can set it on 6.5 inches or 9 inch.
Which is better?

I have no low water pick up on my Yamaha.

 

[aaronmt]

I would not run it without a low water pick up at all!!!!!!!!!!! Last summer I had my complete built and rebuilt yammi on my GS.Short story I broke the lower unit that had a lwp.I then put a standard non lwp lowered the motor alot and went back out.Needless to say the motor got overheated and blew(no water guage was hooked up yet).I did have the motor quite low where I thought for sure would be enuff.I personaly think the way teh water comes off the back of the allisons it wont work without lwp.Im sure you could burry real low but it make the boat drive very poorly.Send the lowerunit out while your rigging the boat.I will never run another allison without lwp period. Aaron

 

[Darth VMAX]

For just fiddle farting around I think you will be ok with-out the LWP. It will make it harder to drive because as mentioned you will need to keep her deeper than what an Allie typically likes. Its not like you are going to be trying for top speed anyways (you have to crawl before you walk ;-) I think 6.5 would be a good starting point because your motor is 468 lbs. This also brings up a great point, make SURE you have a water pressure and I like a temp guage as well. Cover up your speedo too.

I would look at getting the L/U coned though.

 

[froggy]

TurboD,

Two good possibilities:

1.Try to find an HPDI gearcase. This case is not LWP, but it's very close. 2. If you could find a Merc Sportmaster gearcase, the fine folks at HydroTec, in Nixa, Missouri should be able to provide the proper adapter.

froggy

 

[baitcaster]

It is an Allison Jackplate. I can set it on 6.5 inches or 9 inch.
Which is better?

I have no low water pick up on my Yamaha.

I think the issue/opinions of LWP has well expressed. W/regard to the set back, I had a 3.0 L Evinrude 225 on my Alli and it ran very well with 10 inches of set back. Having run a 460+ lb. motor I would suggest setting it at you max of 9 inches., It will also help keep your lower without LWP getting some pressure and would let you run it about 3/4 of an inch to an inch or so higher than the same at 6 inches. In the long run, I would suggest you send the lower off to Titus (Custom Welding and Marine) or Bob's and put the LWP on it.

 

[Lotus 50]

I wouldn't worry about no nose cone if
a) I had water pressure and temperature gages
b) No need for every last potential mph
c) High tolerance for steering

I run my XR4 case 2" below the pad most of the time. These cases are not strong, and running lower lengthens the life. There is more steering work, but its not terrible.

 

[Fishforcash]

Hydrotec has a sweet 175 HPDI case that is worked over and polished. Call Wayne and work out a trade for your 150 case. YOu will get 1.87 gear set and that will be better than your stock 2:1 you have now on the 150.

Run it and if you not satisfied Wayne can fix you up with any combination of Phase kits you wish to go. PHase II bolt ons should put that motor around 210 HP and thats going to push that XB plenty.

All on 91 octane fuel.

 

[nickens21]

Im with Lotus.. Start at 2" below the pad if you are to run the stock gearcase. There is no doubt Allisons run and handle better with a nose cone and lwp. But it will work with stock, motor just needs to be a lil deeper in da water. Sounds like you will be fine with what you want to do with your rig so you will be ok.. Just make sure she is gettin plenty of H20 pressure and watch the temp.. Good Luck....

 

[turbo d]

For just fiddle farting around I think you will be ok with-out the LWP. It will make it harder to drive because as mentioned you will need to keep her deeper than what an Allie typically likes. Its not like you are going to be trying for top speed anyways (you have to crawl before you walk ;-) I think 6.5 would be a good starting point because your motor is 468 lbs. This also brings up a great point, make SURE you have a water pressure and I like a temp guage as well. Cover up your speedo too.

I would look at getting the L/U coned though.

I gonna install a water pressure and a temp meter.
And i gonna look for a Low water Pick up.
But what do you mean with: Cover up your speedo too? What is the reason?