Upgrading my 300xs

[sammythebull]

thank you and keep us informed this is a great stuff your giving to us all im sure a few of us will be following in your foot steps

[TUNNEL T]

wow !!!its been awhile sounds like things are getting all worked out . so this hydro tec tuner where do i find it ? TUNNEL T

[NAVISPEED1]

http://www.shop.hydrotecmarine.com/main.sc

[baja1000]

Merctek what going on on the 300xs hop ups

[merctech5591]

Merctek what going on on the 300xs hop ups

everything is cool still dealing with an off idle miss betwekk 1200-1500 rpm. with the hydrotech tuner it is alot better than with a stock cut tuner. what ever anyone does do not cut you tuner. they are hard to find and crazy money from merc. i am setting my liberator to run in dsra this year. i will be runnig the 300xs in performance bass and ski. i will have to remove all the bolt ons and run in stock form. minus the rev limiter. i did some testing last weekend and the people i was with are very impressed the way the motor pulls. even with a 6800 limiter i need more rpm's. with a small 22 et the motor will spin up to 7100 thn just go super fat. i have talked to simon and he has a plan for me. here is a comparison with a xb02 with a 260 he had to add 2 people in the boat to get the weight he would have to run for dsra pbs.this motor pulls like a train with the small wheel.i am working on getting it to leave flat but that is also in the works. these motors are the future of drag racing and i plan to prove that.

http://www.youtube.com/watch?v=jlktHMTUqq0

http://www.youtube.com/watch?v=rBISL1jErpw

[Liberator*21]

Sound cool as hell, keep us posted on your results and changes............

[aaronmt73]

Merctech,are you running the poppet diverter now or did you take it off.I have the a 250xs with flywheel and hydrotec tuner.Im debateing wether to put on or not and what the andvantage would be of it.

[merctech5591]

Merctech,are you running the poppet diverter now or did you take it off.I have the a 250xs with flywheel and hydrotec tuner.Im debateing wether to put on or not and what the andvantage would be of it.

depending on what year 250 you have . they have diff adaptor plates. from 09 and on the 250 and 300 used the same adaptor plate that would dump loads of water from beside the pisser. running the simon popet valve allows the water to dump on the side of the pan instead of in the middle. a few people complained about getting water into the cowl on the 300xs and saturating the foam. this is an easy way to fix that problem

[aaronmt73]

depending on what year 250 you have . they have diff adaptor plates. from 09 and on the 250 and 300 used the same adaptor plate that would dump loads of water from beside the pisser. running the simon popet valve allows the water to dump on the side of the pan instead of in the middle. a few people complained about getting water into the cowl on the 300xs and saturating the foam. this is an easy way to fix that problem

Powerhead is a 04 and the adaptor plate/mid section is a 06 225 standard optimax.I spent a lot of time cleaning up the poor casting.Its a perfect match now from the powerhead all the way to the hydrotec tuner..Whats your oppinion on which way to go with this set up.Thanks Aaron

[merctech5591]

i would try the poppet valve and get some water out of the mid. regap plugs to .045 and see if that heps any. what boat are you running?you will see better gains with a lighter more efficient hull.

[aaronmt73]

i would try the poppet valve and get some water out of the mid. regap plugs to .045 and see if that heps any. what boat are you running?you will see better gains with a lighter more efficient hull.

The motor is on a 98 22ft Velocity.It ran 70 with a standard 225 opti.Hopefully this 250xs with Simon ecu/flywheel,hydrotectuner and Poppet diverter will give it a difference.Im not sure how much actuall hp difference there will be.

[merctech5591]

the new motor should be alot more peppie. it does run the higher fuel/air pressure, has reeds and light comp pulley

[Kcraft]

everything is cool still dealing with an off idle miss betwekk 1200-1500 rpm. with the hydrotech tuner it is alot better than with a stock cut tuner. what ever anyone does do not cut you tuner. they are hard to find and crazy money from merc. i am setting my liberator to run in dsra this year. i will be runnig the 300xs in performance bass and ski. i will have to remove all the bolt ons and run in stock form. minus the rev limiter. i did some testing last weekend and the people i was with are very impressed the way the motor pulls. even with a 6800 limiter i need more rpm's. with a small 22 et the motor will spin up to 7100 thn just go super fat. i have talked to simon and he has a plan for me. here is a comparison with a xb02 with a 260 he had to add 2 people in the boat to get the weight he would have to run for dsra pbs.this motor pulls like a train with the small wheel.i am working on getting it to leave flat but that is also in the works. these motors are the future of drag racing and i plan to prove that.

http://www.youtube.com/watch?v=jlktHMTUqq0

http://www.youtube.com/watch?v=rBISL1jErpw

I know this an old thread but would like to know what was the best prop you used for drag racing a stock 300xs,

[bradmd]

whatever happened to these hydrotec merc tuners? They dont have them listed on their website now.

[baja200merk]

I dont drag race but from the sounds of it a big block with 1.62 and a small block 1.87 both with the same pitch will get you close. Again I'm no pro

EDIT: WOW old thread...