Tuning Questions

[Blackout]

I finally got my Speedmaster .45 in the water. I am still breaking in the motor, but have a few questions. The engine is an O.S. 46VX-M with a Macs 7.5 marine pipe at 11 7/8" long. I have no idea what speeds I am running, but when I go from 3/4 to full throttle there is no change in engine speed. Is this a sign of a rich engine or too long a pipe? Or a combination of both? My high speed needle is only at 1 turn out, but I had to convert to a remote needle so I am using a 9B remote needle. This needle is really designed for a .67 and up engine. Prop is a stock X450/3. Thanks for any help.

Here are some pictures of the boat.

 

[TimothyJones]

I run my surface drive Mono with a Cmb at 9-1/2" (from the glow plug to the widest part) and thats with a 455/3 blade.

It gets on the pipe at 3/4 throttle. Looking at your pics it looks way long,also get you a 45 needle the 67 will be hard to fine tune.

Your pipe is measured around the exhaust curve which makes the pipe alot longer than,lets say a exhaust that comes out the back of a motor IE: Mac,CMB,Picco 45's.

Tim

I finally got my Speedmaster .45 in the water. I am still breaking in the motor, but have a few questions. The engine is an O.S. 46VX-M with a Macs 7.5 marine pipe at 11 7/8" long. I have no idea what speeds I am running, but when I go from 3/4 to full throttle there is no change in engine speed. Is this a sign of a rich engine or too long a pipe? Or a combination of both? My high speed needle is only at 1 turn out, but I had to convert to a remote needle so I am using a 9B remote needle. This needle is really designed for a .67 and up engine. Prop is a stock X450/3. Thanks for any help.

Here are some pictures of the boat.

 

[dwilfong]

I run my pipe at 9 1/2 on my CMB 45RS with a x455/3 also. But every set up is different! Stay with the x450/3 till you get the motor broke in then start shorting the pipe. 11 7/8 is real long try 10 1/2 for now then step up the prop after break in to the x452 and see what you got. then start to shorten the pipe. The x450 is a very good prop for a 40 mono if you can rev the motor. Raced one this weekend no mods just sharpened and worked good on my worn out motor and 93deg air at 75 dew point.

No one prop will be the golden bullet when the air changes the prop will change it is the easiest way to tune the boat to the air. The needle won't make it go faster.

David

 

[TimothyJones]

I love racing my 40 and we need more of them. Stick with it!!!!!!

It is my favorite boat but my eagle sgx runs a close second.

Tim

I run my pipe at 9 1/2 on my CMB 45RS with a x455/3 also. But every set up is different! Stay with the x450/3 till you get the motor broke in then start shorting the pipe. 11 7/8 is real long try 10 1/2 for now then step up the prop after break in to the x452 and see what you got. then start to shorten the pipe. The x450 is a very good prop for a 40 mono if you can rev the motor. Raced one this weekend no mods just sharpened and worked good on my worn out motor and 93deg air at 75 dew point.

No one prop will be the golden bullet when the air changes the prop will change it is the easiest way to tune the boat to the air. The needle won't make it go faster.

David

 

[dwilfong]

I love racing my 40 and we need more of them. Stick with it!!!!!!

It is my favorite boat but my eagle sgx runs a close second.

Tim

I run my pipe at 9 1/2 on my CMB 45RS with a x455/3 also. But every set up is different! Stay with the x450/3 till you get the motor broke in then start shorting the pipe. 11 7/8 is real long try 10 1/2 for now then step up the prop after break in to the x452 and see what you got. then start to shorten the pipe. The x450 is a very good prop for a 40 mono if you can rev the motor. Raced one this weekend no mods just sharpened and worked good on my worn out motor and 93deg air at 75 dew point.

No one prop will be the golden bullet when the air changes the prop will change it is the easiest way to tune the boat to the air. The needle won't make it go faster.

David

Racing against Gene Mongar this weekend came in second over all took him in heat 3 and would have if not for a bum call in heat 2 put me down a lap. still almost caught him from a lap down. DNS first heat getting use to the new setup. He got me in the last one by a hair. No eng left at that point. Not much you can expect when you can push the piston out the top of the sleeve.

Love 40 mono best bang for the buck.

David

 

[TimothyJones]

I don't want to hyjack his thread but we have him on the right track.

Can you tell I like twincraft!!!LOL

The Red one is mine,the Blue one is Debbies(my girfriend) Hence the Journey sticker.

I have alot of those stories LOL.

Joe Warren hates me!!!!!!!!!

BY THE WAY, I REALLY LIKE YOUR BOAT BLACKOUT.

Tim

I love racing my 40 and we need more of them. Stick with it!!!!!!

It is my favorite boat but my eagle sgx runs a close second.

Tim

I run my pipe at 9 1/2 on my CMB 45RS with a x455/3 also. But every set up is different! Stay with the x450/3 till you get the motor broke in then start shorting the pipe. 11 7/8 is real long try 10 1/2 for now then step up the prop after break in to the x452 and see what you got. then start to shorten the pipe. The x450 is a very good prop for a 40 mono if you can rev the motor. Raced one this weekend no mods just sharpened and worked good on my worn out motor and 93deg air at 75 dew point.

No one prop will be the golden bullet when the air changes the prop will change it is the easiest way to tune the boat to the air. The needle won't make it go faster.

David

Racing against Gene Mongar this weekend came in second over all took him in heat 3 and would have if not for a bum call in heat 2 put me down a lap. still almost caught him from a lap down. DNS first heat getting use to the new setup. He got me in the last one by a hair. No eng left at that point. Not much you can expect when you can push the piston out the top of the sleeve.

Love 40 mono best bang for the buck.

David

 

[Blackout]

Thanks guys!

Timothy, can you still get Twincrafts new?

 

[Glenn Gates]

I love racing my 40 and we need more of them. Stick with it!!!!!!

It is my favorite boat but my eagle sgx runs a close second.

Tim

I run my pipe at 9 1/2 on my CMB 45RS with a x455/3 also. But every set up is different! Stay with the x450/3 till you get the motor broke in then start shorting the pipe. 11 7/8 is real long try 10 1/2 for now then step up the prop after break in to the x452 and see what you got. then start to shorten the pipe. The x450 is a very good prop for a 40 mono if you can rev the motor. Raced one this weekend no mods just sharpened and worked good on my worn out motor and 93deg air at 75 dew point.

No one prop will be the golden bullet when the air changes the prop will change it is the easiest way to tune the boat to the air. The needle won't make it go faster.

David

I,m starting to like the 40 Monos Too- I don't have one but put one together for a friend here in UT(4300 ft. elevation). It runs well with the pipe @ 11" with a smaller P-230 prop. Hull is a 40" Microburst w/ a MAC 45.

Good Luck,

Glenn

 

[Blackout]

Here is a short video. This was this past weekend, the pipe is still long and the mixture is rich.

http://www.youtube.com/watch?v=PhDbu8KlGSM&feature=channel

 

[Blackout]

Here is another video, same day. I know, not 100% safe, but the dock is two feet off the water, so the boat would just drive under....

http://www.youtube.com/watch?v=phrFsgtZO7c&feature=channel

 

[Blackout]

I ran the boat today with the pipe at 10 3/4" long. The engine woke up a bunch. The needle is still a little rich. I have a Foretrex 301 GPS coming next week. I'll get some top speeds and try to tune further.

 

[TimothyJones]

Look'n good. Great video. looks like ya'll are having a blast.

I see a couple of future racers. let us know how that gps does for you!!

Tim

I ran the boat today with the pipe at 10 3/4" long. The engine woke up a bunch. The needle is still a little rich. I have a Foretrex 301 GPS coming next week. I'll get some top speeds and try to tune further.

 

[Sean Bowf]

I run my speedmaster with a .45 CMB HR in it. Cooper pipe is at 9 7/8 inch from the center of the cylinder to the weld on the pipe. I run an X450/3 that I detounged.

I don't claim to be any sort of "go to" person when it comes to setting up boats. When mine is running right it is hard to keep the wet side down and the pointy end forward. I will need to see if I can find my old phone to see the pics of the GPS to remind me of my the top speed I got out of it.

Would love to hear anything you learn about setting up the boat.

Does your hull have a hook in it?? Two .45 speedmasters I have seen do (mine and another). Was going to fill it in this summer and see what happens...

Sean

 

[Blackout]

I run my speedmaster with a .45 CMB HR in it. Cooper pipe is at 9 7/8 inch from the center of the cylinder to the weld on the pipe. I run an X450/3 that I detounged.

I don't claim to be any sort of "go to" person when it comes to setting up boats. When mine is running right it is hard to keep the wet side down and the pointy end forward. I will need to see if I can find my old phone to see the pics of the GPS to remind me of my the top speed I got out of it.

Would love to hear anything you learn about setting up the boat.

Does your hull have a hook in it?? Two .45 speedmasters I have seen do (mine and another). Was going to fill it in this summer and see what happens...

Sean

I'll check for a hook tonight. I bought the hull a couple years ago from Mark at HTB Boats. I did a search on 45 mono speeds and found that you stated a speed of 55 mph, but the boat would flip at that speed.

 

[NAMBA860]

I run my speedmaster with a .45 CMB HR in it. Cooper pipe is at 9 7/8 inch from the center of the cylinder to the weld on the pipe. I run an X450/3 that I detounged.

I don't claim to be any sort of "go to" person when it comes to setting up boats. When mine is running right it is hard to keep the wet side down and the pointy end forward. I will need to see if I can find my old phone to see the pics of the GPS to remind me of my the top speed I got out of it.

Would love to hear anything you learn about setting up the boat.

Does your hull have a hook in it?? Two .45 speedmasters I have seen do (mine and another). Was going to fill it in this summer and see what happens...

Sean

I'll check for a hook tonight. I bought the hull a couple years ago from Mark at HTB Boats. I did a search on 45 mono speeds and found that you stated a speed of 55 mph, but the boat would flip at that speed.

any time an engine runs faster at 3/4 throttle then full throttle the engine is lean. the pipe is to long you have the right prop on it. so shorten the pipe richen the engine and let it rip. i dont run .45 engines with that wrap around heder but i can tell you i run my pipes at 9.5 inches from the back of the case where the header bolts on to the weld or high spot in the pipe.

 

[Blackout]

I run my speedmaster with a .45 CMB HR in it. Cooper pipe is at 9 7/8 inch from the center of the cylinder to the weld on the pipe. I run an X450/3 that I detounged.

I don't claim to be any sort of "go to" person when it comes to setting up boats. When mine is running right it is hard to keep the wet side down and the pointy end forward. I will need to see if I can find my old phone to see the pics of the GPS to remind me of my the top speed I got out of it.

Would love to hear anything you learn about setting up the boat.

Does your hull have a hook in it?? Two .45 speedmasters I have seen do (mine and another). Was going to fill it in this summer and see what happens...

Sean

I'll check for a hook tonight. I bought the hull a couple years ago from Mark at HTB Boats. I did a search on 45 mono speeds and found that you stated a speed of 55 mph, but the boat would flip at that speed.

any time an engine runs faster at 3/4 throttle then full throttle the engine is lean. the pipe is to long you have the right prop on it. so shorten the pipe richen the engine and let it rip. i dont run .45 engines with that wrap around heder but i can tell you i run my pipes at 9.5 inches from the back of the case where the header bolts on to the weld or high spot in the pipe.

Good info.

But, the engine did not run faster at 3/4 throttle, it ran the same as at full throttle. The engine acts rich on the stand in the typical manner, head temps are cool at 135 degrees (Measured about 15 seconds after engine shutdown.) , and still running the same glow plug with almost 1 gallon of fuel. I agree that the pipe is most likely still too long, so I'll surely test shorter lengths. Also, with the pipe now at 10 7/8" the engine speeds up a bit after 3/4 throttle.

 

[Blackout]

I run my speedmaster with a .45 CMB HR in it. Cooper pipe is at 9 7/8 inch from the center of the cylinder to the weld on the pipe. I run an X450/3 that I detounged.

I don't claim to be any sort of "go to" person when it comes to setting up boats. When mine is running right it is hard to keep the wet side down and the pointy end forward. I will need to see if I can find my old phone to see the pics of the GPS to remind me of my the top speed I got out of it.

Would love to hear anything you learn about setting up the boat.

Does your hull have a hook in it?? Two .45 speedmasters I have seen do (mine and another). Was going to fill it in this summer and see what happens...

Sean

I checked my hull and yes, it has a slight hook.

 

[Blackout]

I GPS'd my Speedmaster at 48.4 mph today. I didn't change anything from the last time I ran the boat, but I am pretty sure the needle is no longer rich. I didn't change the needle but when throttled on shore the engine reved pretty easy without bogging. I guess the air could have changed....

If engine temps are good and the glow plug does not burn out, is it safe to assume that I am not too lean??

Oh yah, 48.4 was on 25% nitro fuel. What is normally gained by jumping to 50%?? Though this engine may not like 50% in stock form....

Thanks.

 

[Blackout]

I ran 51.3 mph today. Pipe is at 10.5" and I can't make it much shorter as the 180 degree header contributes to much of the length. I found too lean as the boat went slower, so I richened it back up two clicks to get the 51.3 mph. I think I need to restrict the water cooling as the boat seems to run faster after about 3 laps. I assume this is because the engine finally gets up to temperature.

 

[Terry Keeley]

I ran 51.3 mph today. Pipe is at 10.5" and I can't make it much shorter as the 180 degree header contributes to much of the length. I found too lean as the boat went slower, so I richened it back up two clicks to get the 51.3 mph. I think I need to restrict the water cooling as the boat seems to run faster after about 3 laps. I assume this is because the engine finally gets up to temperature.

Cut the water back and richen the needle, it'll respond much better and run faster!