1600 Miles+$600 in Gas = Merc 280

[hotdaddy27]

So Blizz what do you run?

You seem to be quite impressed with the torque/power of the 3.0 L motors, is that what your experience is with?

 

[JUPITER PULSARE]

Hey JP,

Humor me cuz I am not real up on the XRI's. That is 2.5 L displacement....correct?

I love the colors on your boat by the way.

Thanks Hotdaddy. The 225Xri is the first year of the EFI motor. They are 3.0 liter motors. In 1995 the EFI electronics were Mercury's own...1996 and later, Mercury contracted Motorola to build the electronics for the EFI..

 

[JUPITER PULSARE]

JP yours is running well but that's the joy of torque from a fishing style motor loaded unloaded almost the same speed without having to change everything. Oh yeah and how many pounds did you remove from your hull when you redid it?

I would guess that the weight savings by removing the foam and using Mantex for the stringers is about 100-150 lbs...More important than the weight savings was improving the structual integrity of the hull. Checkmate built the Pulsares with a cutout over the fuel tank. (Exposure for moisture/rot and flex in the floor) It was not a solid piece of ply accross the floor. They also left a good portion of the fuel tank under/behind the rear seat exposed. I ran a solid floor all the way accross the fuel tank leaving only the aft end exposed to be able to get to the fuel sender/fills, etc. The other factory problem was the "ply sub floor" under the fuel tank for drainage being completely water logged. It was removed and replaced with glassed in PVC pipe for drainage. Lastly, by installing the small Teak locker between the front seats, I was able to glass the underside of the floor to the stringers and bulkhead!

 

[Blizz]

Yeah i remember your rebuild very nice work. As for what i run these days nothin much i just get to setup a few here and there 2 of the last were pulsares one with the promax the other with a250xb.

 

[C-mate 280]

I have a 2.5 280hp on my pulse 186

I havn't been at this site for a few years but I have a fair amount of experience with a Pulse 186 and the 280 Merc. I realize the boats are different with yours having more lift and is about 100 pounds lighter but here is my 2 cents worth.
I run 10 inches of set back on a CMC hydrolic jack plate, prop shaft all the way up to 1/2 inch below the pad. I have the sportmaster lower unit and I run a labed 24 inch Lightning ET prop that has been tweeked to 25. I turn 7800 rpm and gps at 88 mph. I think I could get 90 if I experimented with other props and had 2 more inches of set back.
I live in Minnesota and Supreme Marine sets up alot of racing rigs, says the Pulsar needs at least 10 inches of set back and probably more with that light 2.5 engine. Its my feeling that if you are going to run 8800 rpm, any thing bigger than 25 inches is tooooo much and probably you would be better with a 23/24 inch prop. I don't think you will run 1000 rpm more than me and if you did, (the math says you will go in the upper 90's with a 25 inch prop at 8800 rpm and that ain't gona happin). You will need a prop that has a lot of bow lift. Experiment with as many props as you can!!!
By the way I burned my engine up 4 years ago and it has the 7800 rpm limiter on it. If you run yours much at 8800 it ain't gona last too long. The cause was bad gas which had some water in it. I now run aviation fuel and have used only Mercury racing oil. Its a hassle but a new power head is $7000. I also installed a water temp gauge and an exhaust gas temperature gauge which I watch closely when I am over 7000 rpms.
My boat runs dead smooth, no chine walk, no bouncing when the motor is way up but when I lower it just a little (1inch) it will start to chine walk a bit, so rig it so that the motor can raise way up.
My boat is noisy and the cops are always doing a sound check,( I am barely under the DB limit and mine has the underwater exhaust). I can't imagine what yours sounds like. My son says he can hear that high wine when my boat is 3 miles away. He and his buddies say it sounds really cool but the neighbors have a different opinion.
Goodluck and keep it under 8200rpm

 

[WILDMAN]

Well, my flamer turns 8800 rpm's. You can always look forward to cleaning the aluminum out of the cowl pan after you stick a piston, the rod pulls out, and goes through the block! Sure does sound good till that happens. If you keep it 7500-7800, it will live for a while, but I'm over the unreliability of the high reving 2.5's. Good luck, and buy stock in Alcoa! Here's what 8800xtwo sounds like.

http://my.break.com/Member/Profile/mypage.aspx?MemberNickName=Randycorson

 

[viper1996]

You will smoke every jet ski thats on the Ct river with ease with that badboy!!! Al...

 

[hotdaddy27]

Thanks for the info guys..

As I posted earlier I def. plan to keep the R's down, I don't want to rebuild a motor any time soon! Even if that means lower speeds.

I hope I can keep up with some Jet Skiis on the CT!!!!

Later.

 

[175checkmate]

The lake lice won't stand a chance.

 

[C-mate 280]

The 2.5 280 has tons of torque for skiing

I water ski all the time with my 186 Pulse with the 280. There will be no problem unless you use a chopper. I use the 24 Lightening ET for both speed and water skiing but the 24 inch trophy is fab for hole shots and skiing. Just lower the jack plate to get some bite. I did notice that when I added more set back the added weight slightly slowed getting out of the hole. If you use a prop that has thru the hub exhaust it is important to use the proper sized cavitation plugs, They are the removable rubber plugs on the hub, Too small and the motor won't spool up to its power curve and if too large, the prop won't bite. That Trophy is a blast out of the hole and the top speed on my boat was 83 and that is with a blue demo prop. If it was labbed perhaps a few more mph.

 

[hotdaddy27]

Nice work C-Mate 280...that was precisely what I wanted to know. I will keep your posts close over the next few weeks as the rigging begins.


I am thinking 12" of setback with the shaft somewhere close to where you have it.

You are thinking 90mph on yours huh... Wow! Congrats.