300XS first run on a 21RT

[Groper]

300xs, with a 1.75 Torque Master lower.

Took the family out to Havasu and Parker for a 6 day trip. About 7 hrs to break the 300xs in, boy does it run great, quiet and great fuel consumption.

I tried (2) different types of props, both four blades, 26p Brovo 1 & a 26p Hill Eagle, both worked well, but the Hill having a small hub, spun easer out of the hole, then hooked up and was gone !!

A few notes: 26p Bravo 1 35mph @ 3500rpm's
26p Hill 40mph @ 3500rpm's

I did not run the Bravo at any top speeds, only during break-in.

With the Hill, it ran 73mph @ 5700rpm's
Air temp about 105deg,
windy and 1-2'+ chop

It ate up the chop and was very stable all the way through the rpms Im sure it has more in the right conditions, a very fun boat to drive, with no steering pull at all.

Was able to stay on plane @ 20 mph, using the adj. 12 x 12 plates, for dragging the kids around, and made for a great wake for inflatables.

 

[Faceaz]

Got any pics? That sounds like a great set-up. :thumbsup

 

[Groper]

Got any pics? That sounds like a great set-up. :thumbsup

This all i have

 

[BajaMike]

More pics? It sounds like a great setup.

 

[DRIVE BYE]

what do think of that hill prop pulling skiers?

 

[GASchiada]

I just set up a 21RT with a 300X and was curious as to what size offset bracket you are using?

 

[Groper]

I just set up a 21RT with a 300X and was curious as to what size offset bracket you are using?

Edited: my bad I was incorrect, it is a 16" setback

 

[GASchiada]

Was there any formula you used to determine that 11" was the correct offset? Mine is at 13" and it seems a little stern heavy and wants to porpoise at times. When I changed from a 225 ProMax to the 300X (about 150lbs heavier) I also changed from fixed tabs to hydraulic and have found that I need to lower the tabs at 70mph or it will start to porpoise. I've been debating whether to reduce the offset, move one of the batteries to the bow, or just keep using the tabs. Thoughts?

BTW, very nice job on the restoration.

 

[RiverDave]

I'd like to see some more pics of the boat.. . Not sure if I saw it out there or not as there was a couple of rts running around.

 

[Fltplan]

Was there any formula you used to determine that 11" was the correct offset? Mine is at 13" and it seems a little stern heavy and wants to porpoise at times. When I changed from a 225 ProMax to the 300X (about 150lbs heavier) I also changed from fixed tabs to hydraulic and have found that I need to lower the tabs at 70mph or it will start to porpoise. I've been debating whether to reduce the offset, move one of the batteries to the bow, or just keep using the tabs. Thoughts?

BTW, very nice job on the restoration.

Somebody on here explained it very well to me. The porpoising is caused by the hull packing enough air to lift, but not enough to withstand the hull all the time. You can eliminate it by accelerating through it faster, which shouldn't be a problem with that motor! My daytona will do the same thing if I try to creep from 70-80. Have to go pretty quickly through the transition. Once it lifts up all the way, it's heaven! :thumbsup

Maybe this is all a moot point with those tabs, just thought I would put in what I learned here! Have fun and nice looking ride.

 

[c'mondriver]

I'd like to see some more pics of the boat.. . Not sure if I saw it out there or not as there was a couple of rts running around.

Agreed More Pic's Please...:thumbsup

 

[Groper]

Was there any formula you used to determine that 11" was the correct offset? Mine is at 13" and it seems a little stern heavy and wants to porpoise at times. When I changed from a 225 ProMax to the 300X (about 150lbs heavier) I also changed from fixed tabs to hydraulic and have found that I need to lower the tabs at 70mph or it will start to porpoise. I've been debating whether to reduce the offset, move one of the batteries to the bow, or just keep using the tabs. Thoughts?

BTW, very nice job on the restoration.

Thanks,
mine will porpoise a little between 25-30 then it settles down without the plates down, the plate are set a few deg. up or not flat.

When the motor was bolted on the bracket, the installer mounted it with one top bolt showing, even though I told them that I can move it up & down. they said thats where you want it.

It might be too high, Im going to lower it and see what happens then, it might solve the problem.

 

[Groper]

I'd like to see some more pics of the boat.. . Not sure if I saw it out there or not as there was a couple of rts running around.

Sorry Dave, I don't how to double "quote"

There were (2) OB's

I was at Parker from wed to sun, then Havi till sun night last night, I was with the group on the beach @ BW, they said they talked to you.
Also saw you and Stacy cruising with the newborn floating in front of BW. Im usually in motion, sorry I missed you.

 

[Cole Trickle]

Boat looked good out there last week....

Nice meeting you and your family at the sandbar.

Brandin

 

[DRIVE BYE]

Was there any formula you used to determine that 11" was the correct offset? Mine is at 13" and it seems a little stern heavy and wants to porpoise at times. When I changed from a 225 ProMax to the 300X (about 150lbs heavier) I also changed from fixed tabs to hydraulic and have found that I need to lower the tabs at 70mph or it will start to porpoise. I've been debating whether to reduce the offset, move one of the batteries to the bow, or just keep using the tabs. Thoughts?

BTW, very nice job on the restoration.

I have the same set up. 21 rt with a 300x. it is rigged with a 13" stand off mounted 9" above the keel. what lower and prop are you running? i have no problems at speed and dont use the tabs.:hmm

 

[nextasex]

You're boat looked awesome Bill! What a great set up you have.

Was hoping to see RD somewhere on the river as I haven't seen him in years. Maybe another time!

Frank

 

[GASchiada]

I have the same set up. 21 rt with a 300x. it is rigged with a 13" stand off mounted 9" above the keel. what lower and prop are you running? i have no problems at speed and dont use the tabs.:hmm

I have SportMaster lower 1.62 ratio turning a 24P Trophy Plus (the only prop I have tried thus far). The motor is mounted with the prop shaft about 1-1/2" below the bottom. It seems to really need the tabs at least level with the boat bottom or I need to trim in the motor to keep the bow from porpoising.
What is your set up (lower, height, prop, rpm, speed)? Also, do you have two batteries in the back and how far forward are your fuel tanks?

 

[DRIVE BYE]

Gas, my set up is close to yours. 1.62 sportmaster lower, trophy plus 4 blade 19P 2 batteries in the back. Fuel tanks from transom to 68"forward. With my jack plate lowered all the way, prop shaft centerline is 3" below bottom of keel. With 3 peeps and all the stuff, it will do 6300 rpm in the low 70's. I dont use my tabs at all. I dont think moving a battery will help your set up. Have you tried contacting Lee?:hmm Also, my motor is mounted all the way to down position on jack plate bracket.

 

[138]

The 300xs look great on that boat. You need to lower the engine to 3 to 3 1/2 inches below the bottom for you to get rid of the hop and add to your top speed. You know that boat got a 3rd place at Catalina in f2 in 2003. Your boat was very good to me. Top speed I ever achieved was 73 with a stock 260. Have fun with her? I have some great memories from that boat.

 

[GASchiada]

Gas, my set up is close to yours. 1.62 sportmaster lower, trophy plus 4 blade 19P 2 batteries in the back. Fuel tanks from transom to 68"forward. With my jack plate lowered all the way, prop shaft centerline is 3" below bottom of keel. With 3 peeps and all the stuff, it will do 6300 rpm in the low 70's. I dont use my tabs at all. I dont think moving a battery will help your set up. Have you tried contacting Lee?:hmm Also, my motor is mounted all the way to down position on jack plate bracket.

I think I might have more weight aft since my offset is 16" and my tanks are about 25 gallons each but shorter, only 48" long from the transom. I might have too much offset for the weight of the 300X but I'll first try lowering the motor to 3" below and maybe give Lee a call. You said you had a jack plate, have you tried different heights?

BTW, are you sure you're spinning a 19P and or your tach/speedo are right? It would seem virtual imposible to hit low 70's with that pitch at 6300. If prop slip was estimated at about 8% that would calculate to 64mph.

 

[Groper]

The 300xs look great on that boat. You need to lower the engine to 3 to 3 1/2 inches below the bottom for you to get rid of the hop and add to your top speed. You know that boat got a 3rd place at Catalina in f2 in 2003. Your boat was very good to me. Top speed I ever achieved was 73 with a stock 260. Have fun with her? I have some great memories from that boat.

Thanks Carl
Had it out last weekend in Long Beach, teaching the wife how to drive it, it was pretty rough, scared the crap out of her, after an hour she felt better about the whole experiance, we had a great time.

 

[DRIVE BYE]

I think I might have more weight aft since my offset is 16" and my tanks are about 25 gallons each but shorter, only 48" long from the transom. I might have too much offset for the weight of the 300X but I'll first try lowering the motor to 3" below and maybe give Lee a call. You said you had a jack plate, have you tried different heights?

BTW, are you sure you're spinning a 19P and or your tach/speedo are right? It would seem virtual imposible to hit low 70's with that pitch at 6300. If prop slip was estimated at about 8% that would calculate to 64mph.

Gas, mine is rigged with a Stainless marine standoff box / Jack plate. I have not tried dif heights. As far as #s thats what the gps said. maybe prop has been re worked. I am the recent 3rd owner of this boat so im still sorting everything out myself. It handles really well with this trophy plus. I bought a Hill Eagle 26 4 blade and the boat doesnt like it. :hmm

 

[Groper]

Lowered the motor by (1) bolt or 1" it's mounted as far down as it will go.
It still porpoises a bit, I did notice better water pressure though !!

 

[franky]

you will never get speed with the drive so far in the water. That thing must not carry the bow very well either, must plow pretty good...what say yee? Think about it, with that much set back the water height at the drive is even higher. You must have to trim the hell out of it to get the bow up. I say lift that thing!!! We had to run the Sleek (same type hull) 1" below the bottom (rules) and wanted it higher for sure.

 

[Groper]

you will never get speed with the drive so far in the water. That thing must not carry the bow very well either, must plow pretty good...what say yee? Think about it, with that much set back the water height at the drive is even higher. You must have to trim the hell out of it to get the bow up. I say lift that thing!!! We had to run the Sleek (same type hull) 1" below the bottom (rules) and wanted it higher for sure.

No, no plowing, it gets on top, and very little trim it will set on it tail a cruises very nicely.
I do have the adjustible Jack Plate, when I do raise it, I will loose a little bit of water pressure, with no gain in speed.
The way the Jack Plate/Bracket is setup, it raised the motor quite a bit off the transom, even with it all the way down.

You can see it the Pic, how the the plates are raised higher than the bracket by 2 or 3 in's.

 

[GASchiada]

I've found that I need to run the tabs at least level with the bottom of the tunnel or the bow feels light and wants to porpoise. I wish I had mounted the tabs so they aligned with the bottom in the full up position (to basically resimble what I had before with the fixed cav plates). Then I wouldn't have to lower them every time.

BTW, do you have a position indicator on your tabs (I was thinking of adding one).

 

[hallett21]

No, no plowing, it gets on top, and very little trim it will set on it tail a cruises very nicely.
I do have the adjustible Jack Plate, when I do raise it, I will loose a little bit of water pressure, with no gain in speed.
The way the Jack Plate/Bracket is setup, it raised the motor quite a bit off the transom, even with it all the way down.

You can see it the Pic, how the the plates are raised higher than the bracket by 2 or 3 in's.

Are you using gps to find your speed #'s? If you are raising and not seeing any gain in speed I would think that means you need to play with propellers more. You said you had a trophy that was a 19 or 21 I believe. Maybe try a bravo one xs that's like a 22? The blades will be bigger so as the lower unit goes up you will still have blades in the water. I think running a 28 may be a little too much prop if your not seeing any gains. Did you lose rpm with the 28 propeller?

 

[138]

Maybe try a bravo one xs that's like a 22? The blades will be bigger so as the lower unit goes up you will still have blades in the water. I think running a 28 may be a little too much prop if your not seeing any gains. Did you lose rpm with the 28 propeller?

A 28 is way too much prop for that boat at any motor height you will never get the revs out of it.

The bravo one xs or a hydromotive http://www.hydromotive.com/int_quad4_OT.html. The 22 or 23 may be right just matters what gear ratio, and what case you purchased.


What gear ratio? 1.62:1 or 1.75:1 ? Is it a TM or a SM case?

By the way the jack plate you have a photo of is not meant for 300xs and you definitely should not be out in big water with it. There are some good ones out in the market that were manufactured for the 300xs but that is not one of them.
Would you like me to check my parts to see if I have a jack plate or an offset plate that might suit your needs? I think I have an extra Stainless Marine offset bracket that was made for the 300xs. Let me know.

 

[Fltplan]

I run a bravo xs prop- 28p. Id like to get a 29p just to keep rpms lower at cruise. Im on a 21 daytona. Probably a difference with the tunnels but try an bravo xs prop. They are different than a bravo. You shouldn't have a prob w a 28 and a 300xs. I run the same jack plate as my 2.5/260. Both Dcb and Kevin at Kmg said it would be fine. Its considerably larger than the one pictured and it has the transom savers on the inside.


Sent from my DROIDX using Tapatalk

 

[138]

You shouldn't have a prob w a 28 and a 300xs. I run the same jack plate as my 2.5/260. Both Dcb and Kevin at Kmg said it would be fine. Its considerably larger than the one pictured and it has the transom savers on the inside.


Sent from my DROIDX using Tapatalk[/QUOTE]

I could be wrong but that 300xs is bit heaver. And as as for your Datona and the Schiada rt are way diferent boats. There is no way you should pull a 28 and if you do not get into the power band with the 300xs and run it wide open and can not reach 5900 or so rpm you will blow that motor.

 

[Groper]

Are you using gps to find your speed #'s? If you are raising and not seeing any gain in speed I would think that means you need to play with propellers more. You said you had a trophy that was a 19 or 21 I believe. Maybe try a bravo one xs that's like a 22? The blades will be bigger so as the lower unit goes up you will still have blades in the water. I think running a 28 may be a little too much prop if your not seeing any gains. Did you lose rpm with the 28 propeller?

be safe
Quote:
Originally Posted by hallett21
Maybe try a bravo one xs that's like a 22? The blades will be bigger so as the lower unit goes up you will still have blades in the water. I think running a 28 may be a little too much prop if your not seeing any gains. Did you lose rpm with the 28 propeller?
A 28 is way too much prop for that boat at any motor height you will never get the revs out of it.

The bravo one xs or a hydromotive http://www.hydromotive.com/int_quad4_OT.html. The 22 or 23 may be right just matters what gear ratio, and what case you purchased.


What gear ratio? 1.62:1 or 1.75:1 ? Is it a TM or a SM case?

By the way the jack plate you have a photo of is not meant for 300xs and you definitely should not be out in big water with it. There are some good ones out in the market that were manufactured for the 300xs but that is not one of them.
Would you like me to check my parts to see if I have a jack plate or an offset plate that might suit your needs? I think I have an extra Stainless Marine offset bracket that was made for the 300xs. Let me know.

Im running a 26" Hill Eagle four blade, Torque Master, 1.75 ratio.
I called Detweiler and told them what I was mounting on the Bracket, and they said it was ok !

Carl I'll call you........

 

[GASchiada]

Groper,

When I rigged my RT with the 300X, I had two motor brackets made. One at 13" and the other at 16". I have been using the 16" but the boat seems too light in the bow (like the center of gravity is too far aft) because of this I needed to keep the motor tucked in a little (especially if anyone was in the back) to keep the bow from bouncing. So this weekend I exchanged the 16" for the 13" and it seems to have much better balance and I can now use the trim to control bow lift. If you experience similar symptoms you may also consider trying a shorter bracket.

 

[Fltplan]

You shouldn't have a prob w a 28 and a 300xs. I run the same jack plate as my 2.5/260. Both Dcb and Kevin at Kmg said it would be fine. Its considerably larger than the one pictured and it has the transom savers on the inside.


Sent from my DROIDX using Tapatalk

I could be wrong but that 300xs is bit heaver. And as as for your Datona and the Schiada rt are way diferent boats. There is no way you should pull a 28 and if you do not get into the power band with the 300xs and run it wide open and can not reach 5900 or so rpm you will blow that motor.[/QUOTE]

The 300xs is 505#, my 2.5/260 was 360# I believe, so it's definitely more weight. I'm not sure what you mean with not pulling 28p on the daytona? I can run it any rpm. It will go right to the rev limiter or cruise around at 4k. This motor has so much torque all over that I don't really notice a "power band" like a stroke dirt bike.

I guess I was pretty fortunate to just bolt this motor on and have the boat handle well at all speeds.

 

[138]

I could be wrong but that 300xs is bit heaver. And as as for your Datona and the Schiada rt are way diferent boats. There is no way you should pull a 28 and if you do not get into the power band with the 300xs and run it wide open and can not reach 5900 or so rpm you will blow that motor.

The 300xs is 505#, my 2.5/260 was 360# I believe, so it's definitely more weight. I'm not sure what you mean with not pulling 28p on the daytona? I can run it any rpm. It will go right to the rev limiter or cruise around at 4k. This motor has so much torque all over that I don't really notice a "power band" like a stroke dirt bike.

I guess I was pretty fortunate to just bolt this motor on and have the boat handle well at all speeds.[/QUOTE]

I was talking about the schiada.. I hope your datona will pull a 28. That schiada will not and if you do not get close to the revs at wide open you will blow the the 300xs. But I do not know the boat or the merc 300xs very well.

 

[barbara08]

300xs, with a 1.75 Torque Master lower. Took the family out to Havasu and Parker for a 6 day trip. About 7 hrs to break the 300xs in, boy does it run great, quiet and great fuel consumption

 

[DRIVE BYE]

What kind of boat?

 

[Groper]

300xs, with a 1.75 Torque Master lower. Took the family out to Havasu and Parker for a 6 day trip. About 7 hrs to break the 300xs in, boy does it run great, quiet and great fuel consumption

What kind of boat?

Im "ASSuming" the on in this thread, a 21RT