How do I make my boat go faster..1995 70hp 17ft bass boat 53mph plus

Anyengine

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. I came here to see if anyone would but was put down by a know it all factory timing is 17deg and I run 30deg BTC and my 25hp will run with 40hp Yamaha on the same boat... simple modification running the 70hp for nine years and the 25hp for 6yrs.. Found here 98% guess and retest.. No actual good step by step and a 2 stroke is so simple.
 

Anyengine

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. I came here to see if anyone would but was put down by a know it all factory timing is 17deg and I run 30deg BTC and my 25hp will run with 40hp Yamaha on the same boat... simple modification running the 70hp for nine years and the 25hp for 6yrs.. Found here 98% guess and retest.. No actual good step by step and a 2 stroke is so simple.

40 years of engine repair,, Anyengine
 

flyingscott

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I was the know it all and your timing should be 19 deg not 17. I think your whole post is BS i have owned all 3 of those motors. The 25 Evinrude will not keep up with a Yamah 40. Your conclusions belongs in a Harry potter book.
 

roscoe

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. I came here to see if anyone would but was put down by a know it all factory timing is 17deg and I run 30deg BTC and my 25hp will run with 40hp Yamaha on the same boat... simple modification running the 70hp for nine years and the 25hp for 6yrs.. Found here 98% guess and retest.. No actual good step by step and a 2 stroke is so simple.


I came here to see if anyone would

Would what ?


was put down by a know it all factory timing

What is a know it all factory timing ?


my 25hp will run with 40hp Yamaha on the same boat..

Yes, two motors mounted on the same boat will be traveling at the same speed.


No actual good step by step and a 2 stroke is so simple.

I look forward to you contributing your actual step by step.

I was told I need at least a 90 hp my boat, but if you can help me to get my
Evinrude 50, 2 cycle 2 cylinder running faster, I'm sure it will do fine.

I am particularly interested in the rpm your 25 is turning.
 

jimmbo

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.but was put down by a know it all


You were Chastised for bumping a Thread that had been asleep for a few years. Only the OP/Moderators are allowed to wake a Sleeping Thread.
As for this Thread... It appears you are Trolling, but

A 25 in good condition can keep up with a worn out/mistuned 40, or if they are on their trailers, being towed down the Interstate
 

Sea Rider

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2-4 stroke standard carbed motosr runing at sea level should run with their own timing advance tech specs specified for each HP motor brand. Adding slight + more time advance along burning less fuel octane accounts for slight better motor performance when boating at very high elevations and with no possibility to get high elevation jets nor less pitch props to play with.

Happy Boating
 

Anyengine

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Ok a forged piston with a modified unbreakable forged Diesel ring for the top with less angle beveled and ceramic coted head..
 

jimmbo

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Problem is, when adding extra Advance on a 2 stroke Outboard, you aren't going to hear the Detonation before serious damage is done
 

Scott Danforth

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Ok a forged piston with a modified unbreakable forged Diesel ring for the top with less angle beveled and ceramic coted head..

My father spend 20 years making diesel rings..... have yet to find a forged one.
 

Anyengine

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They are French and modified .. manual Evinrude Johnson service manual 1990-2001 page 2-92 engine timing for 18-35hp 31.8cid timing BTC 28 to 31deg Free manual at Boatinfo.no and has all the makers.. and I think MAHLE has the rings now.
 

Scott Danforth

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Mahle offers cast rings, and I do not know of a diesel motor with pistons that small, except maybe lombardini

however they have different bores.
 

Watermann

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Interesting place to start such a thread with all the experienced boaters that we have around here.

It takes a bunch of power to push a weighty bass boat over 50 MPH. Is your boat stripped out to be like a lightweight glass speed boat and have a padded hull? Do you have a low water pick cone up on the motor with a jack plate or short shaft and are you running a cleaver or chopper prop? If not then no way, I'd be surprised if it would make 35.

One thing we all know is that 2 stroke motors come from the factory being what they are, with little if any ability to be more than what they are as far as HP goes even with great expense.
 

Scott Danforth

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a 2-stroke would take a tuned exhaust to get a lot of power out of a 25hp power head

amcm3.jpg
 

flyingscott

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This needs to die! The OP makes no mention of a 35 hp carb or intake which would be needed to produce any where near 40 hp. All he mentions is a magic piston ring and a ceramic coating.
 
Last edited:

Scott Danforth

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This needs to die! The OP makes no mention of a 35 hp carb or intake which would be needed to produce any where near 40 hp. All he mentions is a magic piston ring and a ceramic coating.

you do realize that now we are just having fun.... the magic unobtanium piston ring and the custom tuning with vaporware and fairy dust is what makes the world go 'round
 

Anyengine

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They are French and modified .. manual Evinrude Johnson service manual 1990-2001 page 2-92 engine timing for 18-35hp 31.8cid timing BTC 28 to 31deg Free manual at Boatinfo.no and has all the makers.. and I think MAHLE has the rings now.

MAHLE makes unbreakable rings for CUMMINS diesel.. when I here Diesel and I work on them and Detroit and CAT..bout 7 years ago I was doing some extra work European shop for there computer controlled VW diesels when they could not repair them and the parts guy got them I think something to do with VW turbo diesel racing made in Germany.. no one to do machine work but while repairing the backup Generator at FN machinegun plant found a machinist he like idea and did it and I think is the week link.. To fix my RPM problem CDI pn-113-2453 no rev limit and mod to carb and exhaust.. as for Yamaha I stated keep up on a 14ft hightide don't care about speed .I leave that to everybody else . I did it for fun when the engine was apart and to make it as efficient as possible air in and exhaust out.. But when the racers are at the river getting drunk on the sand bar and the river is calm I my shoot by 10 min later someone comes up the creek to see what's on the back of my boat. as for my 70hp no one will ever know..oh well never wrote on a blog or forum and will it to everybody else..
 
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