I am considering having an exhaust tuner installed and having the exhaust ported on my 96 150FS. What are the pros and cons of this procedure. I am also considering adding carbon reeds as opposed to the OE reeds.
I am currently running 5600rpms at wot with a OMC Renegade 25 pitch and getting 57.1 GPS. This is on a 96 Javelin 389TE. I am looking to break 60 if it is possible.
I would not suggest you do either, this is my take on Hop ups....If you don't try to get all you can from set up then you are putting the cart in front of the horse.
What are you refering to as missing in the set up? Am I missing the forest for the trees so to speak?
Con: If you (or whomever does the work) screws up on the porting by as little as .005", you can have a very expensive peice of uselss metal sitting on your workbench. The more you hop it up, the less life the motor will have. I spent lots of $$ and time hopping up my Yamaha to race, only to turn around and get rid of it, tired of having to tinker on the dang thing all the time afterwards.
Leave that baby alone!!!! It's cheaper!!!!!!!
What can be done to improve speed without putting anything else into the motor? Maybe a different prop? Is so what type and pitch? What should the max rpms be on this motor?
I probably should have added that I am running a 6" jack plate I am not sure as to pad to shaft distance after tunning it in. I brought it up from 3.5 below untill it got right hand steering torque. I then lowered back down 1/4 inch and brought it up another 1/8 untill steering was close to neutral while on pad. Spray is behind the pole for the the rear fishing seat. Water pressure is holding apx 20psi and the rooster tail is about even with the top of the cowl.
I would definatly try another prop before I went to grinding...
Try a 24 Raker and then maybe some work to the prop. I have a friend with a 389- 150 hp setup that runs over 60 easily. He is runing a 24 Raker.
If you're turning the Gade to 5600 with a 150, I think you need to go to set up. Those are good rpms for a 150 on the 25 pitch, The 23 Gade will get ya some more R's but I don't think that's what you need. JMHO
You are right in the meat of the powerband for that motor. It should already be a 60 mph boat.
Now everyone here knows that I love to hop up motors but in your case it isn't going to give you very much. It would cost you 3k to get 5 mph. Is that worth it?
OK, that said what you need is a hydrolic jackplate. At least an 8 incher. This will allow you to raise your motor to take advantage of less drag and then lower it to get on plane easier. My guess is you will see a 2-5 mph increase with the hydro. You will probably have to re-prop to find the best prop.
Your engine height right now is to low for max performance, how do I know this. Because you have it set for nuetral steering torque. This means that your torque tab is deep enough in the water to actually work. This is where the hydro jack helps. For cruising you can set it for nuetral torque and jack it up when you want speed.
The small bore loopers are lousy hop up candidates anyway. 3K only gets you 200 ponies. Better to spend your money elsewhere.
Well after spending a few hours on the phone I am going to try some different props to see the difference on the rig. According to the prop slip chart, I have 22% slip. This seem a little too much to me.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Neveredge »</TD></TR><TR><TD CLASS="quote">You are right in the meat of the powerband for that motor. It should already be a 60 mph boat.
Your engine height right now is to low for max performance, how do I know this. Because you have it set for nuetral steering torque. This means that your torque tab is deep enough in the water to actually work.
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I aggree that it should be a 60 MPH boat, but it isn't yet.I have ran the motor all the way up to 2 inches below pad before, and only got 51 MPH out of her. Not to mention the rooster tail was 4-5 feet higher than the cowl.
I'll just have to take her back out with some different props and see what she'll do.
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