Other PHP 937 or DASA 970?

[chadetroit]

Engine builder battle! Kidding. Good informative discussion and very helpful for those of us looking to go beyond the 760BB SS engines. Is surprising there are no dyno benchmarks for any engines, why is that?

 

[KTM434]

Because there are 2 different ways to build an engine on a dyno. One way is to build an engine for the purpose intended based on your knowledge of 2 strokes and air flow characteristics and port size/shape/timing then put that built engine on a dyno as your baseline and use the dyno to tune your carbs, headpipe, nozzle diameter and impeller pitch etc. To get the most power and best torque curve out of that engine possible but not just focusing on the max horsepower numbers.

The other way is to focus on your max horsepower output and not care how this engine pulls down low or how quickly it will rev to max RPM under a load and not caring about anything but the max HP numbers. You can port the engine for full airflow and cylinder stuffing at high RPM just to achieve those numbers. Then use the dyno to get the most RPMs out of that engine since that's where torque falls off and horsepower takes over. Once they tune it to the highest HP numbers they can achieve... they post it online or in a magazine and 90% of the people don't realize that those numbers done mean schit when you don't ride in that RPM range and will never get to the sweet spot of that engine. Dynos should be used as a tuning tool not a horsepower building and sales marketing assistant.

 

[Big Kahuna]

Because there are 2 different ways to build an engine on a dyno. One way is to build an engine for the purpose intended based on your knowledge of 2 strokes and air flow characteristics and port size/shape/timing then put that built engine on a dyno as your baseline and use the dyno to tune your carbs, headpipe, nozzle diameter and impeller pitch etc. To get the most power and best torque curve out of that engine possible but not just focusing on the max horsepower numbers.

The other way is to focus on your max horsepower output and not care how this engine pulls down low or how quickly it will rev to max RPM under a load and not caring about anything but the max HP numbers. You can port the engine for full airflow and cylinder stuffing at high RPM just to achieve those numbers. Then use the dyno to get the most RPMs out of that engine since that's where torque falls off and horsepower takes over. Once they tune it to the highest HP numbers they can achieve... they post it online or in a magazine and 90% of the people don't realize that those numbers done mean schit when you don't ride in that RPM range and will never get to the sweet spot of that engine. Dynos should be used as a tuning tool not a horsepower building and sales marketing assistant.

Glad to know at least one person gets it. Great post!

 

[Supajet]

Because there are 2 different ways to build an engine on a dyno. One way is to build an engine for the purpose intended based on your knowledge of 2 strokes and air flow characteristics and port size/shape/timing then put that built engine on a dyno as your baseline and use the dyno to tune your carbs, headpipe, nozzle diameter and impeller pitch etc. To get the most power and best torque curve out of that engine possible but not just focusing on the max horsepower numbers.

The other way is to focus on your max horsepower output and not care how this engine pulls down low or how quickly it will rev to max RPM under a load and not caring about anything but the max HP numbers. You can port the engine for full airflow and cylinder stuffing at high RPM just to achieve those numbers. Then use the dyno to get the most RPMs out of that engine since that's where torque falls off and horsepower takes over. Once they tune it to the highest HP numbers they can achieve... they post it online or in a magazine and 90% of the people don't realize that those numbers done mean schit when you don't ride in that RPM range and will never get to the sweet spot of that engine. Dynos should be used as a tuning tool not a horsepower building and sales marketing assistant.

Wouldn't it be pretty hard to hide this if you posted the read out ? Anyone who has the slightest idea of how to read a dyno could see this was the case in seconds, and use this information to make a clear decision based on what they want out of their ski.

I have always found this extremely strange coming from modifying cars. Nothing gets a second look based on a feeling, everyone demands a dyno readout before making a decision on a turbo kit exhaust etc. On here it seems people just say it "Hits Good" which just seems to be subjective and unscientific. If i were spending this kind of money on a motor I would want to know exactly what I was getting into.

 

[Matt_E]

If i were spending this kind of money on a motor I would want to know exactly what I was getting into.

No ski motor builder is going to give you dyno numbers. Nothing credible, anyway.
Most people don't know any better and want HP numbers. HP is tied to torque at any given RPM. Peak HP is most likely high in the RPM band where it is nearly useless in a jetski motor. Torque at low and mid RPM's is far more important here.

In an application with a gear box (cars, bikes, everything but jetskis) the motor can be operated in the peak HP region without too much trouble.

 

[Supajet]

I do not understand why they could not post up a dyno / credible information ? I understand how important tuning is, but there doesnt even seem to be a baseline.

Sure your average Toyota Camry buyer cant be bothered to understand the application of torque and HP, but this site is full of enthusiasts whom I would think are quite capable of figuring out how to read a dyno graph and understand how it applies to how they potentially want to use their ski. Without this information this decision is left to the engine builder and the buyers just sort of take their word for it (not saying the word of the engine builders is bad) I would just like to know for myself.

 

[Matt_E]

but this site is full of enthusiasts whom I would think are quite capable of figuring out how to read a dyno graph and understand how it applies to how they potentially want to use their ski.

LOL. I wish I had your faith in people.

 

[deftons56]

LOL. I wish I had your faith in people.[/COLOR]

And i wish your posts were easier to read in the "darkness" mode... Not that you ever have anything useful to say. oke::joke:

 

[masterblaster]

Bottom line is they know anyone thats spending this kinda money on a motor is for the most part a motor head and knows how to read a dyno charts curve..Reading the rpm based torque curve is pretty simple for your average backflip feen. Its just too much trouble for them to do it,that along with the fact most consumers would be shocked at how low the peak #s really are on these motors. There is no standard calibration for these type dynos as there are on the 2 types primarily used in the automotive field. So the peaks would mean very little and are completely subjective. All motors would have to be tested on the same dyno at the same time from diff builders after they were tuned tits on in the water.. We do this all the time in the car world..Supra nationals in Texas is a good example..every yr builders from all over the country come to Pit there motor builds against the best in the world..to Compete ...All of them use the same Dyno while everyone is there so there are no variables.

In the standup jetski motor industry,no one really cares,its just to much trouble for them, along with being scared to compete and get beat and loose market share.Its too easy to say this motor RIPS and be done with it.....Trust me thats never gonna change in this industry unless something major different happens in yrs to come

 

[Matt_E]

And i wish your posts were easier to read in the "darkness" mode... Not that you ever have anything useful to say. oke::joke:

You're using the wrong theme. :biggrin:
I didn't know it doesn't show up right in the darkness theme.

 

[SmittySX]

This is turning into a very pricey build pretty quickly... You only live once, right? ha!

 

[SmittySX]

So if i go with the 1100 im not sure what kind of ignition i want to go with yet... I will probably run the b pipe until i can afford the pfp. What would be good set of carbs to get? ( im not looking for top of the line as im on a budget... if there is a such thing as a budget!)

 

[Matt_E]

You need big carbs on a big engine. While I wouldn't call BlackJacks budget carbs anymore, a set of dual 48 BlackJacks is still cheaper than the alternatives (NOVI and Full Spectrum) and will do the job just fine.
You're still looking at $1k just for those, though. You need a good intake and reeds, too.

Really, do not skimp on accessories for such an engine. Don't forget about a big mag pump, either. Don't even think about running a stocker.

 

[KTM434]

^^ what he said. If you're trying to go budget then start with a smaller engine with all the best bolt ons (total loss, 48mm carbs, PFP, 144-148 mag pump, good intake/reeds, and then step up to the bigger engine that will benefit from all the mods you already have.

 

[Tommygunz]

So if i go with the 1100 im not sure what kind of ignition i want to go with yet... I will probably run the b pipe until i can afford the pfp. What would be good set of carbs to get? ( im not looking for top of the line as im on a budget... if there is a such thing as a budget!)

I have a set of Riva 48's on my PHP 898 and they work awesome

 

[onlyFX-1]

Like said above, getting all the good bolt on's is better than a big engine with the wrong bolt on's. Going with the cheaper PHP 937 and spending the extra money you saved from not getting the DASA on stuff like MSD tl, NOVI 48s, PFP, big pump will be better...
Just my .02

 

[masterblaster]

i guess you could say i am. ideas i suggest are now being used by some of the biggest names in the trade. pretty sure the guy you are referring to is trying to do something i suggested years ago. which is also why i'm running a powervalve polaris motor. stupid high port timing.... but it's about setup.

let's think about what you just said. "it sucks that by them starting to machine the cylinders like that, it's taking the option away from the consumer." if they were that bad it wouldn't hit....





stock strokes from dasa and x metal both suck. i tried to get this going about two years ago. put motors offered by builders with there tuner there to set it up on a dyno. not for peak hp or anything, but to see a general powerband. no takers. i even had one respected engine builder here pm asking me not to do it. if you doubt me and my abilities, come to the free ride and give a ski i built a shot.

thats funny...so typical of this industry..I see in a prev post in this thread you said you would provide the dasa motor and the dyno? what dyno are you speaking of,where is it located?We have a few motors of diff brands and builders we could provide..I still cant believe no one has had any success getting something like this setup for daytona when all these motors,builders,tuners are all in the same place...with everybody who is anybody there to impress and verify all results..you know how many people would spectate and support this if anyone had any balls to compete in it?

I go to alot of large Motorsports meets of all types and have friends that go to even more, Cars,motorcycles,sleds,boats. Any large gathering has a dyno on site and is a large part of the meet. Even the ones that dont enter or compete,know what hp and torque their setups make..Go to the biggest jetski meets in the world and almost no one even knows the hp,much less the power curve of their setup,all they know is "It rips"...lol really no huh.... whats funny is most of these tiny 2 stroke simple jetski motors,cost more than 500 hp 4 stroke very complex motors...funny how that works ehhhh.

 

[102nd7]

You know its funny you made the comparison of cost I've been trying to wrap my mind around it myself.

 

[FearMyWrX]

Like said above, getting all the good bolt on's is better than a big engine with the wrong bolt on's. Going with the cheaper PHP 937 and spending the extra money you saved from not getting the DASA on stuff like MSD tl, NOVI 48s, PFP, big pump will be better...
Just my .02

YUPP! Plus, that'd be PLENTY for your BOB!

 

[chadetroit]

I imagine a good chunk of cost is just the size of our sport. If you want a stock yami case and cylinder those can be had for cheap. If you want a custom billet case and or cylinder, those are made by small shops in small quantity runs. No large production so it's manufacturing 101. We'd all love to see lower cost engines but with the 2 strokes becoming more rare I think we got what we got and while I hate paying a lot more than the other sporting industries have to pay I appreciate we do have shops that have dedicated themselves to providing the brap to the small colony of riders that want it.