300X DBR kit

[Wild Bill]

Talked to Dave Busch Racing yesterday, he was telling me about a reflash, tuner and a big throttle body to get a little more power. My question is has anybody tried this setup and what did you think about it? I would like more input before I do something like that.

[merccrazy]

Anyone that talks reflash is looking for trouble.

[25two.stroke]

We have run some 300x on small boats out here in California before having them flashed and after having him flash...and after some of his other performance mods. Not the best advise cause you probably have a bigger boat...but there was not really a noticeable increase in power on the small boat. However, the 300x is already kinda overpowered for the STV and the Allison we ran em on...so its hard to say. Bumping the compression and flashing the ecu did get better acceleration, but I can't say there was any more top end power there. We ran a DBR built and ported 300x on an allison, then took it off and put a bone stock 300x on the same boat with same prop and all and it performed essentially the same. Hope that helps at least a little bit.

[Wild Bill]

Thanks 25 and merc, that is the info I am looking for. It is on a 95 21 Daytona, so it is the right size boat. I would hate to swap out the parts for almost nothing. I guess I will leave it alone and try a little more pitch to pull the motor down to its max HP. It would be nice to see 110 on the gps.
Wish they made a 500 LB 400R.

[merccrazy]

Your best bet is to buy one that's already done and has the results.

[KIRCHNER]

DONT waste your money, keep the revs down & have fun. most aftermarket stuff is wishfull thinking,, buy PROPS!

[johnmiffco]

DONT waste your money, keep the revs down & have fun. most aftermarket stuff is wishfull thinking,, buy PROPS!

agree 100%
the 300x is in my opinion the best 300hp motor merc made
has good torque for a 3.0 and pulls good rpm
the last of the hot rod 2 strokes
downfall is maintain,,,maintain,maintain,,,
as them heavey pistons on them light duty rods will sling when try to over rev them motors
so flashed ecu with higher rev limit or no limiter ,,,seen many get destryed
if hard core drag motor,,,fine as is part of a race motor
dailer fun motor,,,,,not so good to do all the mods and take chance to shorten life
i have tripps on my 32 and run 100-150 gallons every time i take out
and cruise 4-6 k asll day long
with lots of hrs put on every season
just my opinion,,,
but as stated props,,,,and keep rpm 6500 or below for longer life
than trying to get 1-2 mph and pop,,,,,

[Wild Bill]

I am convinced, I will leave it alone. I guess I will get a 34 pitch prop this winter It spins my 32 Performance propellor drag 4 gets me 107 now maybe a 34 will get that 110 mph. The only problem I have is finding the room to let it wind out to that last rpm.

[25two.stroke]

15" 300X on the stv out here was running a 32 and 33 lightning ET, as well as a 32 Pro ET both were going well past 7000 rpm and not wanting to spin the motor that high to go 130 the owner got a Dewald 34 4 blade cleaver...that made the big difference. Hard pill to swallow at close to $2000, but it got the boat to 134 at about 7100 rpm.

[R.grover]

I have one of there kits and its been great. 21ft ski race boat. over 250hours on it now with no problems. dose everything well.
Like the others have said you will not see much of a gain. i have seen 3-4mph. and could do more of a gain just in props.