Blaster What kind of RPMS are you getting out of your 701's?

[Quinc]

Bought a Tiny Tach ( I wouldn't recommend it, MSD enhancer is too much for it...) Anyway I am hoping to compare numbers with you guys and see if this is what I can expect from my setup or if it can be tuned better.

Water was like glass and it held 7500 for about 10 seconds and averaged around 7300. Elevation 140ft
GPS top speed was 46.8MPH

Waveblaster 1
Mods are:
718cc
Ported ( I think race ported) has a 318 engraved on the side of the cylinder if that means anything to anyone.
91 octane
Coffman exhaust
TDR waterbox
Protec head
46mm taper bore carb
Ocean Pro Flame Arrestor.
MSD Enhancer set to 8000
Stock prop

 

[tshank123]

The RPMs are only part of the story. You really need to GPS it to know what speed you're getting at a certain RPM. You can pitch an impeller to give you higher or lower peak RPM, but the question is at what speed are you spinning those numbers.

 

[High Speed Industries]

I have a 2008 superjet and it runs 7100-7200. I need to gps it because I have no idea how fast I'm going.
Here is my whole setup.
Stock 701 bored .25mm over
Milled head for 91 octane
44mm carbs (off of a 760)
Fiberglass reeds
Msd enhancer
Factory B pipe with a limited chamber
Hooker 9/15 impeller
Solas stator section

I believe I could pull a bit more rpm with my setup if I ported my head pipe and manifold. I also think matching the gaskets to the surfaces would help too. I would love to port my cylinder but that is not allowed in the class that I race in.

 

[Billybo455]

dasa1200 hitting 9250.

 

[Quinc]

The RPMs are only part of the story. You really need to GPS it to know what speed you're getting at a certain RPM. You can pitch an impeller to give you higher or lower peak RPM, but the question is at what speed are you spinning those numbers.

I am wanting to know if it is tuned right. Figure if someone has a similar setup but is getting more rpms then I know there is something amiss on mine. My guess for top speed would be mid 40's. (Doesn't help that I am 240lbs)

I have a 2008 superjet and it runs 7100-7200. I need to gps it because I have no idea how fast I'm going.
Here is my whole setup.
Stock 701 bored .25mm over
Milled head for 91 octane
44mm carbs (off of a 760)
Fiberglass reeds
Msd enhancer
Factory B pipe with a limited chamber
Hooker 9/15 impeller
Solas stator section

I believe I could pull a bit more rpm with my setup if I ported my head pipe and manifold. I also think matching the gaskets to the surfaces would help too. I would love to port my cylinder but that is not allowed in the class that I race in.

I would of thought you would have a higher rpm range with the dual 44's.

dasa1200 hitting 9250.

No one cares about your Dasa.

 

[tshank123]

I am wanting to know if it is tuned right. Figure if someone has a similar setup but is getting more rpms then I know there is something amiss on mine. My guess for top speed would be mid 40's. (Doesn't help that I am 240lbs)

Your peak RPMs compared to somebody else's dont necessarily tell you that its tuned right. You're carbs are tuned right when you get the peak RPMs that your set up gives you. You might take a little fuel off the highs and get 7600, but you dont know unless you do some testing.

Honestly it sounds like you're underpropped a little, probably because the stock impeller is tuned for a stock motor.

 

[dcptr]

Thats some serious RPM, horse power must be up there. What speed were you doing?
Chris.

I think he's just reading out his MSD TL Max RPM/End Retard switch setting

 

[Quinc]

GPS'd her yesterday: 46.8 MPH. @7300rpm's This sound about right or should she be faster with the mods I have?

 

[kevbo]

GPS'd her yesterday: 46.8 MPH. @7300rpm's This sound about right or should she be faster with the mods I have?

Are you sure about the rpm. Most RF tachs are not accurate with MSD. A good stock blaster prop/pump will be turning 6800 at 47mph. Does the pipe hit hard from idle or does it take a second or two to respond? A high port cylinder with stock prop will be a little sluggish without high compression.

 

[Quinc]

Are you sure about the rpm. Most RF tachs are not accurate with MSD. A good stock blaster prop/pump will be turning 6800 at 47mph. Does the pipe hit hard from idle or does it take a second or two to respond? A high port cylinder with stock prop will be a little sluggish without high compression.

I had to wrap the plug wire with insulation and electrical tape (Per Tiny tach tech support) before it would work. It has decent bottom end hit but not near as good as my sj with stock porting. I am going to get some new plugs and try the old fashion way of tuning it. Might also try throwing on a Prok velocity stack and carbon reeds.

From groupK website for a single carb waveblaster 1:
http://www.groupk.com/633and701.html

[FONT=Helvetica,Arial]701 WAVE BLSTR

Stock 43.8 mph
Sleeper 47.5 mph
[FONT=Helvetica,Arial]HMMR [FONT=Helvetica,Arial]51.6 mph[/FONT][/FONT]
[/FONT]

 

[catpower]

Sorry I don't buy the 47 mph stock blaster. I too have a tiny tach, mounted on handle bars so I see live rpm. 6800-6900. Pipe ported prop twin carb ported lighten flywheel yach yach yach. Let's just say a lot of time invested with this 61/62 motor and any mods I've done now since 10-16 prop and 12 vein pump have only slowed me down a few clicks. Max speed done with gps was 49.6 now if ambient temps are just right I get 46-47. Gave up on watching rpms. Prop and pump was just enough improvement to not care so much anymore about top speed. The rpm thing is exactly what your seeing. ?????? What gives.