15 inch mid comparison on 300x

[badluck]

anyone know how much lighter a 15 inch mid is compared to a 20 inch? not just the can but the complete set up.also, what can be done to lighten a 300x?

[rhickox]

Parker Rabe probly knows. He had one on a Mirage i think..

[badluck]

anyone?

[bretter]

not much

[Adam McKeon]

Easiest things to lighten on an 300X or even an XS ,
1. Cowling ( stock XS cowl is 28 lbs ) an aftermarket like my CF cowl is 7 lbs. Stock X cowls are not nearly as heavy.
2. Flywheel 5-8lb Billet flywheel vs the stock which I think is 18 lbs.
3. Tuner
4. Use a Torque Master or even the new Fleet Master VS a Sportmaster. They are all currently using the same internals however the SM is by far the heaviest.

The two style shortened 3L mids that Taylor's make are 42 lbs ( X ) and 32lbs ( 2.5 offshore ).

I would think cutting a stock X can and shafts down would only result in about 6-10 lbs of savings at the most.
Maybe someone who has done or does them will chime in...

[tux974]

IMPO, Not much if any unless you start replacing PH parts like mentioned above. Even at that you will only be losing very little weight, maybe 20lbs and it will be one expensive diet! I you use the 2.5 15" saddle bracket you will put the weight back you cut off the can. The main reason to do something like that is to bring the CG down from the bigger PH'ds. This is very important for better handling on some boats....OH yes, let's not forget the cool factor!!! JM 2cents

[badluck]

Lowering the cg is the main priority. I also want to get the pig on a diet and get it closer to the weight of the 2.5efi that was on it.I have never been happy with the handeling since the 3.0 went on. What does a 2.5 efi 260 with 20 inch standard mid and sporty weigh? I thought it was a 100 to 150 pound lighter than a 300x.

[300x Stoker]

One of the 15" Mid setups uses the 2.5 lower unit??? which is smaller and would help. The boats seem to do OK with the Etec?? and I don't think they weigh less than a 300X. With the Sportmaster you have to have to run it very high or it's a wild ride. I feel your pain.

Who makes the custom lower units? Steckbauer??? If he could put together a tough 200 case with cone the boat should handle good. IMHO

For the peanut gallery,,,If you haven't driven a 20' SST with a 300x,, don't laugh.

[THE HOGG]

I have no idea what it weighs but my taylor mid uses a 2.5 clamp bracket and 2.5 gearcase.

[sleekcraft sst]

It looks really cool ! Lol

[tux974]

The only way to bolt the 2.5 LU to a 15" mid is to go with the Taylor mid but you will still need the 2.5 SS saddle bracket which is heavier due to the 2" setback built into it.
IMPO, 300X power head and a 2.5 LU is a great setup!!

[badluck]

Anyone hAve measurments of the two sportys 2.5and 3.0?

[sleekcraft sst]

I was going to build a 3 liter with a 2.5 lower but I was told the little pump didn't have enough flow at idle to keep the 3 liter block full of water so i went with 15" mid and 3 liter lower . Just keep that in the back of your mind.

[badluck]

Good to know. Did the shorter mid make a big difference vs. The 20 " mid?

[300x Stoker]

I was told you shouldn't put a cone on a Torquemaster or the motor would overhead because of reduced water flow. :eek:

[THE HOGG]

I was going to build a 3 liter with a 2.5 lower but I was told the little pump didn't have enough flow at idle to keep the 3 liter block full of water so i went with 15" mid and 3 liter lower . Just keep that in the back of your mind.
They lied to you. The little pump in its stock form has no problem keeping my simon 3l cool. And contrary to what some say you can put 1.62 gears in a 2.5 sporty as well.

[badluck]

Hey Tom,who is this lower unit guy that modifies these things? Do you have a contact?

[sleekcraft sst]

I'm running coned torque master and have no problems at all .

[300x Stoker]

David Steckbauer at 920-231-1149 is what I had written down but don't know if it's still good contact info? A coned Torquemaster is another thing I wanted to try because I've heard they could run better on our boats than the 3L Sportmaster??


Hey Tom,who is this lower unit guy that modifies these things? Do you have a contact?

[mrcrsr]

The only way to bolt the 2.5 LU to a 15" mid is to go with the Taylor mid but you will still need the 2.5 SS saddle bracket which is heavier due to the 2" setback built into it.
IMPO, 300X power head and a 2.5 LU is a great setup!! the only problem w/ that tony is you are now stuck w/ a small water pump compared to the 3 litres larger pump, motors tend to run warm w/ that setup,others have not had problems though, not to mention the 3 litres gears are bigger/ heavier duty. the cross section of the 3 litre case is roughly the same(it uses the same bearing carrier as the 2.5) so not sure it would be worth the loss of strength.

[tux974]

the only problem w/ that tony is you are now stuck w/ a small water pump compared to the 3 litres larger pump, motors tend to run warm w/ that setup,others have not had problems though, not to mention the 3 litres gears are bigger/ heavier duty. the cross section of the 3 litre case is roughly the same(it uses the same bearing carrier as the 2.5) so not sure it would be worth the loss of strength.

Charlie, Water was never an issue. The 3.0L case is heavier, he is looking to drop weight and always has water problems unless you spend $500 + in upgrades. 3.0L cases have always been a headache when run high and hard. The 2.5 will also run faster and handle better. JMPO from experience.

[mrcrsr]

i'd be scared to run one on the skater w/ the beating that thing takes in choppy water, you here it grabbing and breaking loose all the time, i had a 2.5 sporty and 3 litre sporty apart side by side last week, the gears were bigger and beefier in the 3 litre case, i guess on a lite boat where you're looking to save weight it would be a different story. incidentally, the 3 litre flywheel in stock trim is slitely over 13.5 lbs, it can be reduced to 10 plus lbs w/ some litening. tony, why would it handle better? i'll have to look at both again

[tux974]

Look at the area above carrier, that in it self will make for better handling not to get into more details. Mercury is also very aware that area is a weak point but have no choice due to the 3.0L not being able to dump exhaust through the mids like a 2.5. They do not have exhaust snouts like the 2.5. As far as breaking cases any case behind a Skater or cat up high will be a liability and guarantee to take a beating. I have seen the 3.0L completely break off above the carrier and many have had that area crack. I have destroyed my share and would never be afraid to run a 2.5. The 2.5 case was also made with a gusset in that area for a reason!
What I have found to be a real/possible issue running them up high is the skegs and they both are the same. The reason for the gears being a little bigger is due to the torque on the 3.0L, not as important for the 2.5.
PS; I'm sure you have done everything possible to your 3.0L setup so when possible try a 3.0L PH with the 2.5 mid & LU and report back :D I say 7+ and you will also find something very important (IMPO) that it handles much better in any speed :D
BTW, I'm not knocking the 3.0L's, I think they are good reliable motors but I just feel they each have the intent use just like a boat. You want a HP setup 2.5, Mercury will even tell you that!! OK enough of typing......Once again JMPO:D

[THE HOGG]

Look at the area above carrier, that in it self will make for better handling not to get into more details. Mercury is also very aware that area is a weak point but have no choice due to the 3.0L not being able to dump exhaust through the mids like a 2.5. They do not have exhaust snouts like the 2.5. As far as breaking cases any case behind a Skater or cat up high will be a liability and guarantee to take a beating. I have seen the 3.0L completely break off above the carrier and many have had that area crack. I have destroyed my share and would never be afraid to run a 2.5.
What I have found to be a real/possible issue running them up high is the skegs and they both are the same. The reason for the gears being a little bigger is due to the torque on the 3.0L, not as important for the 2.5.
PS; I'm sure you have done everything possible to your 3.0L setup so when possible try a 3.0L PH with the 2.5 mid & LU and report back :D I say 7+ and you will also find something very important (IMPO) that it handles much better in any speed :D
BTW, I'm not knocking the 3.0L's, I think they are good reliable motors but I just feel they each have the intent use just like a boat. You want a HP setup 2.5, Mercury will even tell you that!! Once again JMPO:D

that is pretty much what wayne tatlor told me. if I remember right he said the 2.5 case was like 5mph faster in his testing. at any rate, on my vegas xt the only problem I have had with the 2.5 case is the skeg. Broke two so far.. I had a few cooling issues and was going crazy chasing them thinking it was the little pump, but it ended up being the plastic merc part that holds a 3l water tube to the exhaust plate. it was cracked and until it had pressure going to it was barely noticeable, but with pressure it would open up and let all the water out instead of forcing it up.

[tux974]

that is pretty much what wayne tatlor told me. if I remember right he said the 2.5 case was like 5mph faster in his testing. at any rate, on my vegas xt the only problem I have had with the 2.5 case is the skeg. Broke two so far.. I had a few cooling issues and was going crazy chasing them thinking it was the little pump, but it ended up being the plastic merc part that holds a 3l water tube to the exhaust plate. it was cracked and until it had pressure going to it was barely noticeable, but with pressure it would open up and let all the water out instead of forcing it up.

Hogg, Good deal on your findings! Wayne was 100% correct in his statement from experience.
Skegs are a big concern and issue with many cases when they are run high. Do you have a torq tab? If you do try turning the back down some and also take a little off the front to reduce the torq. It will not affect the steering.
BTW, I never had or heard of water issues like Charlie is saying either if everything is setup right and working as it should.

[mrcrsr]

tony, i remember talking to someone about it, the problem he was having is it would run warm at idle speeds and he felt it was due to the smaller pump. tony, as far as the shape of the housing, on the skater anyway, everything is out of the water once up and running, other then the point of the case and down(halfway down the carrier). i understand what you're saying about the gusset though, w/ that part being stronger. i'll try to lay both side by side today and see whats different. i could see the 3 litre pump taking more hp to drive though, as well as the bigger gears, but how much? thanks for your insight tony, i know you've owned quite a few skaters!:D

[Markus]

David Steckbauer at 920-231-1149 is what I had written down

That's what I have, too.

1571 Westhaven Cir
Oshkosh, WI 54904

[mercracer2.5]

Can you bolt a 15" 2.5LU right up to a 15" Taylor mid 3.0L without any modifications?
Thanks

[whipper]

Can you bolt a 15" 2.5LU right up to a 15" Taylor mid 3.0L without any modifications?
Thanks

The 2.5 gearcase bolts up to Waynes SS mid that bolts up to a 3.0lt power head. $1300 bucks :thumbsup: http://www.madefi.com/midsec.htm

BTW Whats a 300X stock weigh? 480lbs? It sounds like makeing them under 450 is quite doable.
The 300 PM weight is around 465lbs. So the X is only 15 lbs more but way more powerfull in stock form. I think i read they made well over 300 on the dynos. Im likeing this thread alot.:D

[THE HOGG]

Can you bolt a 15" 2.5LU right up to a 15" Taylor mid 3.0L without any modifications?
Thanks

No you cannot. The splines are different for the 3l's. That is it though.

[whipper]

No you cannot. The splines are different for the 3l's. That is it though.

Am i reading MadeEFI,s web page wrong or do you need a special shaft made? I thought it read his 15 SS mid fits the 3.0lt top and 2.5 bottom? Does that mean the mid fits like that but you need a special shaft that has 3.0 LT top splines machined? I gather a good machinest could make a shaft that fits the 3.0lt mateing the 2.5 gearset? Yes or No? Sorry if im off base hear I really want to know also??

[bigboy]

Am i reading MadeEFI,s web page wrong or do you need a special shaft made? I thought it read his 15 SS mid fits the 3.0lt top and 2.5 bottom? Does that mean the mid fits like that but you need a special shaft that has 3.0 LT top splines machined? I gather a good machinest could make a shaft that fits the 3.0lt mateing the 2.5 gearset? Yes or No? Sorry if im off base hear I really want to know also??

You are right about that. I believe they actualy cut the drive shaft in two pieces and than weld half of the driveshaft of the 3.0 on the 2.5 shaft....

Should be a sweet setup I think. I think most weight can be saved in the heavy swivel. There is a vendor here "Chapman" who builds some nice units from what I've seen here on this site. He can build a setback and clamp in one so you can get rid of the jackplate and also even end up with a liughter clamp than stock. So 2 times weight savings.

[tux974]

Am i reading MadeEFI,s web page wrong or do you need a special shaft made? I thought it read his 15 SS mid fits the 3.0lt top and 2.5 bottom? Does that mean the mid fits like that but you need a special shaft that has 3.0 LT top splines machined? I gather a good machinest could make a shaft that fits the 3.0lt mateing the 2.5 gearset? Yes or No? Sorry if im off base hear I really want to know also??

That is correct. 3.0L top and a 2.5 bottom. IMPO, Great combo!! That is exactly what you do, cut the shaft and respline with the 3.0L splines.

[mrcrsr]

here's a video of the 3 litre case running surfaced on the skater, i don't see any real differences as to how the 2.5 case would be better in this situation unless it has something to do w/ internal drag inside the 3 litre case or water pump, any explanations?? these videos are taken at 97- 99 mph http://www.youtube.com/watch?v=EiZ5ouu0ITw&list=UUgSQ7afru2XpJD1aS1NwGkA&index=6&feature=plcp http://www.youtube.com/watch?v=5omncGp8E2Y&list=UUgSQ7afru2XpJD1aS1NwGkA&index=4&feature=plcp

[tux974]

Charlie, Just like props bolt the setup to your boat and report back.....I'll leave it at that because we can post for days...:thumbsup:
BTW, I think a 20" 3.0L in the tunnel is totally insane for handling! :eek: They are OK behind the sponson...JMPO

PS; Finito for me here :smiletest:

[mrcrsr]

has anyone ever done the conversion w/ all else being the same-ie, both 20" motors, or both 15" motors w/ the same gear ratio, etc. just trying to justify the cost before jumping in. one thing is for sure, the 2.5 cases are cheaper then the 3 litres! strengthwise though, the 3 litre gears are definetely stronger. as far as driveshafts i'm sure marty powell would be able to do the conversion

[THE HOGG]

Jack at full throttle did the shaft Im running now. just cut the 2.5 splines off and welded on the splines from a 3litre. No comparison for me as it is what I satrted with. I sure do like it though!!

[StrokerOMCSS]

you can get a 3liter upper and a 2.5 lower but you should send your 20 inch shaft to the twins and they will cut it off and respline so there is no welding and you need to send your shifter shaft so they can fit aswell. so yes it is a direct fit you want need any adaptor plates you just have to use the right parts and they can be made to fit. I think to respline is 150 dollars and redo shifter shaft is 75 dollars i think those numbers are pretty close. i have a Evinrude with 15 inch 2.5 clamp bracket TMM 16 inch mid and a 1 inch plate to adapt my 3 liter gearcase if i would have ran a 2.5 gearcase then i wouldnt need the plate but i went 3liter thanks StrokerOMCSS

[badluck]

I would love to see that comparison.I am torn. I had a 2.5 and it handled great. The 3.0 not so much.Is the 3.0 sporty stronger? Is it really needed on a Stoker? Should I swap out to a shorter mid, leave the 3.0 sporty, and modify it? The 15 mid is a must. lower unit is questionable.

[300x Stoker]

If you had a Skater or other full tunnel where the LU got slammed at 100+ I would stay with the 3L Sportmaster. Al has done some mods on the 2.5 Sportmaster that seem to help the boat IIRC, that they used at the last 300 Parker race?????? Or I'm supposing the modded LU they used on the 2L motor was a Sportmaster?:confused:

[mrcrsr]

i should have taken some pics, i had a 3 litre sporty and a 2.5 sporty apart at the same time, the gears were bigger and beefier. i just don't see where the gain would be had, unless it has to do w/ less drag due to the gearset design and smaller pump. one thing that can be said for the 20" mid is the motor doesn't get drowned when coming off plane, went thru that w/ my ally xr2002 w/ a merc 15" mid, they do look cool though:D

[Da Bull]

I`m told that the 3L and 2.5 drive shaft`s are the same at the bottom and will enterchange. Only differance is the spline at the top. Is this true? A bud told me this because he bought two 3L shafts and had them cut to 15inch and reslined for a 2.5 up top. He did this because the 3L shaft does not rust like the 2.5 down around the water pump.

DB

[tux974]

I`m told that the 3L and 2.5 drive shaft`s are the same at the bottom and will enterchange. Only differance is the spline at the top. Is this true? A bud told me this because he bought two 3L shafts and had them cut to 15inch and reslined for a 2.5 up top. He did this because the 3L shaft does not rust like the 2.5 down around the water pump.


DB

This is true!! They also come double bearing and are much cheaper.

[skaterjim]

I have 28 skater 300x and 2.5 lowers and they work very well. it does get a little warm at idle when the impeller gets time on it. I seem to have to change it about twice a year. I saved 40lbs a side but I did go from a stainless hyd. jackplate to a manual cmc plate. also went to the little trim cyclinder. the biggest gain was handeling,lower center of gravity. But also no more water issues in lower. The boat did pick up speed. I have beat it pretty good in rough water and you can see the difference compared to friends 28 skaters in rough water. you can sell all the stuff you take off to offset the cost. I have to say I love it, and would do it again. The twins are very good at it, know exactly how to do it and they did cut and spline my shafts.

[Mike Nass]

I just picked up a 300X and want to convert it to a MADD 15" mid... I have a 2.5, 1.62 Sportmaster that i want to use... sounds like i can order a 3.0 Driveshaft and have it shortened 5 inches? Correct? Any idea what that part number is? I think the shift shaft is different on the bottom for 2.5 and 3.0 sportmasters??? Assuming that is correct, do you weld a 2.5 bottom onto the 3.0 shift shaft?

Cheers,

Mike

[THE HOGG]

I had taylor marine shorten and machine 3 litre splines on my first 2.5 fishing case. They did an awesome job. I could never get the 2.5 fishing case to stay together so i purchased a sportmaster. Rather than send it to them to machine i had jack at ftp cut the 3 litre splines off of the fishing case and weld them on to the sporty case. So either way.

[mrcrsr]

just wanted to give an update, just assembled another 21 skater/300x/sportmaster w/ a built 15" mid(not a factory merc), didn't notice much difference in the way the boat drove compared to my boat w/ the 20" factory mid, but the shortened mid creates several issues, for 1 thing, there is not enough negative trim, and you have to use negative wedges to get some of the negative trim back, secondly, there isn't a trim indicator that will fit the shortened clamp, we've tried several. probably will have to go underneath and tie into the ram for a trim indicator. probably w/ a factory 15" clamp this wouldn't be a problem. but as far as the way the boat drives i'd have a tough time shelling out the money to do a 15", because the benefit so far seems negligable on this application, not to mention that the motor goes half underwater coming off plane

[Air It Out]

Can a 300xs powerhead adapt to a 15'' factory mid the same as the 300x can?