Real performance upgrades?

[Slfmde]

I know about the ribbon delete and could rig up an intake... but I’m looking for substantial power gains. I read RIVA had a turbo kit at one point but it doesn’t seem to be around any longer. Does anyone make a turbo kit for the 1.8 HO in newer AR240’s?

 

[swatski]

Greenhulk's Jerry Gadis had a turbo 1.8 ski that was doing 80+mph. I blew up though.

Real performance upgrade for a 1.8?
- SVHO

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[adrianp89]

With enough money you can do whatever you want. A good shop should be able to build a custom turbo kit. Just remember you need two, I can't imagine it would be any less than 12-15k.

EDIT: Here ya go:

http://www.kommanderind.com/turbo

 

[2kwik4u]

I wonder how quickly you will reach the capacity of the 155mm pump? Yamaha obviously found it very quickly and had to move to a 160mm pump on the AR192's. I'm sure a repitch would be in short order for the new power levels, however, at some point I'm sure you will be limited by the surface area of the blades, regardless of how aggressive you get with the pitch.

Very interesting problem. If I had a spare stack of hundreds sitting around I wouldn't mind trying it out.

 

[GoVols01]

I'm thinking that instead of modifying the engine, try a larger size pump. A friend of mine was surprised that my 360 hp twin engine 212X only goes ~50mph. He said Yamaha must have coupled a conservative pump to the engines.

 

[Jgorm]

Anything it's possible with an unlimited budget and no concern for reliability. My take is that modifying a Yamaha is like modifying a minivan. It's a great family wake sports boat and a terrible speed boat. Maybe a ls swap with a Berkeley pump would do the trick. My plan on going fast is to buy a real jet boat that will do 70mph. Then I'll have the family boat and the race boat. This is cheaper than the just the turbo.
https://sandiego.craigslist.org/esd/boa/d/1973-nordic-jet-boat-built-454/6627721406.html

 

[Adubbs76]

Its funny I was thinking about this the other day. Dose anyone know if the 160mm pump will bolt directly on our boats? I would also think you could add the supercharger and intercooler from the svho directly to our 1.8s?

 

[Mike Byrd]

I think I heard on the Greenhulk forums that the N/A 1.8s have a higher compression than the SVHO 1.8s since they have the supercharger. This may be an issue if you just swapped it over.

 

[Neutron]

I wonder if the mating area from the tunnel to the pump are the same on a 160 and 155mm pump, doubt they are

 

[Jgorm]

I think I heard on the Greenhulk forums that the N/A 1.8s have a higher compression than the SVHO 1.8s since they have the supercharger. This may be an issue if you just swapped it over.

Yeah. Boosting a high compression high rev engine is race gas territory. Ready to pay 10 bucks a gallon or more? Do they have race gas at the fuel dock?

 

[jcyamaharider]

Yeah. Boosting a high compression high rev engine is race gas territory. Ready to pay 10 bucks a gallon or more? Do they have race gas at the fuel dock?

E85 baby!!! Poor mans race gas.

 

[swatski]

I would not be hooking up the 160mm pump to the 1.8 N/A, not enough power, not even close.
Even 155mm impellers with more aggressive pitch do not work.

There are no major performance upgrades for a 1.8N/A. High compression is a major factor, as I understand it, but not the only one. This is a similar situation to MR-1HOs, actually, where not even the legendary Group K could ever improve much on Yamaha.

Now, making some performance improvements is certainly possible, starting with the obvious like ribbon delete etc.
Also - RIVA ECU reflash is wonderful (but that is more so for improving low/mid range and throttle response, not the top speed - the WOT is basically the same).

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[Jgorm]

E85 baby!!! Poor mans race gas.

I would never consider e85 in a boat! That fuel will be sucking up so much water! Don't forget the 35% reduction in miles per gallon!

 

[jcyamaharider]

They do it all the time out this way......of course 2000 hp gator boats rule the river also.

 

[Slfmde]

I understand the limitations and requirements I have turbo vehicles. I don’t want to be the test dummy was hoping someone else already did that lol.

Wish Yamaha would put twin supercharged engines in. Scarab looks to be stepping it up...

https://www.jetskihub.co.uk/single-post/2018/05/10/Scarab-Jet-Boat-300hp-is-here

 

[Neutron]

Twin supercharged 1.8s will drain the tank fast. 50 gallons would not be enough for a day of wakeboarding or tubing.
My FZS SVHO will drain the 18 gallon tank in a little over one hour when running it hard.
Thats a light ski with one engine. Not a 4000lb boat with two

 

[adrianp89]

This is not Yamaha’s market. Simple, efficient, and reliable is their niche. Gas sucking super chargers that need to rebuilt every 100 hours do not fit lol.