300r or 300 proXS on 20' Lake+Bay backwater? Which L/U

**Capt j** · 12-25-2021, 12:39 AM

I have a 2005 20' Lake and Bay backwater with a 250 SHO and it doesn't seem to be as fast as the Mercury boats etc. Current performance is 67 MPH me in it, Bravo XS 25" pitch prop 5900 rpms WOT. Boat is heavy as it has 2 10' powerpoles, a trolling motor with 2 lithium batteries, and 100lbs of fishing gear. I am considering putting a 300 HP Mercury on it. I primarily flats fish in saltwater and runs are generally 30 miles each way. So any advantage of going with the 300R versus a 300 pro XS???? Would you go with a torquemaster or sportsmaster lower unit? I'm mainly concerned about the mid range, but top speed as well is a consideration.

**mjw930** · 12-25-2021, 11:29 AM

I’d do a 300 ProXS with the TMII lower. The smaller case makes prop selection easier and in many cases the SM lower is slower under 85 mph unless you can fully surface it. Even then your boat may like more bow lift than a surfacing SM can provide.

I run a 250 ProXS TMII spinning a 23 Bravo FS to 6200 on my Key West 210 Bay Reef and it’s seen 72 but it’s a major handful. The hull generates so much pad lift above 60 there’s very little boat in the water.

**XstreamVking** · 12-25-2021, 11:38 AM

I vote for 300XS I like the 2 smokes. I still haven't gotten used to the angled shape of the 4 strokes. From what I have read the 250 4s is stronger at the bottom and mid (where fishing boats need it) than the 300r but less top end. Guy on here did the testing. It's in the SOB thread. A bud has a 250 Sho on 20 l&b and I am not impressed. I think the lower is just too big and only works with a 80+mph hull, skimming along with only the skeg and bottom of bullet wet. Doggy out of the hole too...

**Capt j** · 12-25-2021, 01:21 PM

Originally Posted by XstreamVking

I vote for 300XS I like the 2 smokes. I still haven't gotten used to the angled shape of the 4 strokes. From what I have read the 250 4s is stronger at the bottom and mid (where fishing boats need it) than the 300r but less top end. Guy on here did the testing. It's in the SOB thread. A bud has a 250 Sho on 20 l&b and I am not impressed. I think the lower is just too big and only works with a 80+mph hull, skimming along with only the skeg and bottom of bullet wet. Doggy out of the hole too...

I am interested in either the new 4s 300 pro XS or 300R. I have a 2015 250 SHO and spin a Bravo XS 25" 5900 and only get 67 mph. Mid range is great though 4000/48 mph, 4500 56-58 mph. Same boats with the 250 XS opti get 72-73 and a friend just put a new 4 stroke 250 Pro XS on his backwater and got 82 mph out of it.......the Yamaha is a Yamadog. Some people on the Lake and Bay forum claim the sportmaster is 7 mph faster even when the boat is heavy. Others claim you lose mid range.......I'm mostly concerned with mid-range. But like top end as well.

**Turborr** · 12-25-2021, 05:58 PM

If you are not running 85 the sportmaster lower will slow you down. Stick with the torquemaster. I have seen many people trade (with cash obviously) their sportmaster for torquemaster lowers.

**Will hedrick** · 12-26-2021, 03:07 PM

If the whole low water aspect is a big deal, consider coneing a torque m.

**Capt j** · 01-13-2022, 11:15 PM

WELL, just an update. I ordered a new 300R with torquemaster lower. Decided to go DTS and spend the extra money for the rigging. The Pro XS and the 300R ironically were the same price, but the pro XS has a 54 week wait and the 300r will be a June production so that was the deciding factor........

**Will hedrick** · 01-15-2022, 08:03 PM

The only real difference is you get a hand assembled motor with the r, instead of an assembly line of I'm not mistaking

**Z06man** · 01-17-2022, 08:53 AM

300R has different intake runners and possibly different cam on 1 side turns 6400 instead of 6200 on the XS also you can get the heavy duty mid if you want. The sporty on my boat lost 3.5 MPH it runs 78 with Tq master .20 foot YOUNG with 300 and it is heavy.

**Capt j** · 01-17-2022, 10:56 AM

Originally Posted by Will hedrick

The only real difference is you get a hand assembled motor with the r, instead of an assembly line of I'm not mistaking

THe R has shorter intake runners and a 6400 rpm rev limiter versus 6200 versus the new pro xs. I'd imagine the 300R would be capable of putting out 350hp IF Mercury tuned it for 93 octane instead of 87.

I ordered a 300r, CMS mid section, DTS, torque master lower 1.75:1 gear ratio. I really like how the Bravo XS performs on my boat currently, so I'll probably try a 28"p bravo XS to start. I'm hoping motor gets delivered in June.

The break=in for the first 2 hours is going to be a little tough to manage. Going to need a REALLY calm day...... for the first 2 hours vary rpms up to 4500 rpms, run the motor WOT for 1 minute every 10 minutes.