Yamaha 700efi power mods

shonuff

"Kiss My Converse" - UTVUnderground Approved
Jan 15, 2009
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murrieta
i have a friend with a 700efi and he wants to get more power out of it,,, kyle i know you have a fast ride and were doing extensive testing along with unleashed utv on some motor mods (vdi, intake, injector, exhaust). can you guys, or anyone who has something that worked good, please tell me which set-up you found worked best so i can pass the info along.... thanks.
 

1BDDELX

Palmdale...Come Back To Me.... - UTVUnderground Ap
Jan 29, 2009
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Palmdale, Ca
I posted this elsewhere but here is my setup and a few other things

Well I just thought I would share my info with all you guys. I have a 2008 700 with:
1- Dynatech ecu/cdi
2- Dynatech fuel controller
3- Afe intake
4- Modified Sheave
5- Duner kit with the internal springs installed
6- Power exhaust tip
7- Grinded welds on the stock exhaust

I have to say I have had no problems with my Dynatech stuff. After some different tests at 2000-3000' with my mods listed above the best settings on the fuel controller are:
Base 1
Low -2.5 (negative 2.5)
Mid 0
High +5
Curve 2
With this setup I am getting 12.5 to 13.2 or so Air/Fuel mixture and the plug is perfect.

I am able to get 60mph on flat ground.

As of this morning I could almost lift the front wheels off the ground when I floored it from a dead stop. This afternoon I took off the exhaust and grinded the welds off and took a screwdriver and removed all of the slag inside the pipes. I can now pop a 6-12" wheelie(It amazed the [email protected] out of me).

Also make sure the throttle cable is properly adjusted as mine was about 3/16 from hitting full throttle. I only have around 400 miles on it.

I also added two 4" kragen HID's and and I have HID's in the headlight's. With both sets of lights on I can only get 12.5 volts of charging. So it is really close to being tapped out for power.

The duner kit internal springs say they engage at 3000 rpm but after my testing they actually engage between 2500 and 2700 rpm.

Also be aware of the sliders inside the sheave melting. Mine melted around 300-400 miles. Mike at Unleashed has the fix kit.

The valves I adjusted at 40 hours and only one intake valve was off.

I hope this helps out some of you on here.
 
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Mopar

Addicted - UTVUnderground Approved
Jan 15, 2009
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Bako So Cal
Some have had good luck with the Dynatek, Me... not so much. Im one of the many that got stuck with the notorios "popping, missing and sputtering" that the Dyna ECU's for the 700's are now known for.....

Im swapping out for a VDI unit which seems to be a much more reliable unit along with bein able to be tuned for any engine build/mod, including larger injectors.

First i would definately go with some type of Sheave/clutch combo... Unleashed's combo seems to currently be one of the most complete kits out there which includes the fix for the "melting slider" issue on the 700 clutches.

As for exhausts theres not really much to compare... no one is currently using the 700 to its full potential due to lack of correct fuel issues so you cant really tell a noticable difference between exhausts IMO
 
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1BDDELX

Palmdale...Come Back To Me.... - UTVUnderground Ap
Jan 29, 2009
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Some have had good luck with the Dynatek, Me... not so much. Im one of the many that got stuck with the notorios "popping, missing and sputtering" that the Dyna ECU's for the 700's are now known for.....

Im swapping out for a VDI unit which seems to be a much more reliable unit along with bein able to be tuned for any engine build/mod, including larger injectors.

First i would definately go with some type of Sheave/clutch combo... Unleashed's combo seems to currently be one of the most complete kits out there which includes the fix for the "melting slider" issue on the 700 clutches.

As for exhausts theres not really much to compare... no one is currently using the 700 to its full potential due to lack of correct fuel issues so you cant really tell a noticable difference between exhausts IMO
Yes, the exhaust only seems to be benefical if you do internal motor mods. As for my Dynacrap I have had no problems but would probably recommend the MSD or the Vdi if it proves worthy.
 

Mopar

Addicted - UTVUnderground Approved
Jan 15, 2009
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Bako So Cal
Yes, the exhaust only seems to be benefical if you do internal motor mods. As for my Dynacrap I have had no problems but would probably recommend the MSD or the Vdi if it proves worthy.
I havent heard anything negative about the MSD, but the VDI seems to have a little more tunability...
 

Mopar

Addicted - UTVUnderground Approved
Jan 15, 2009
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Bako So Cal
I also heard that it was not as user friendly though.
Thats true... but if your doing bigbore/stoker/bored throttle body/intake/exhaust than you should be going to a dyno shop anyhow....

Msd is good for the user that adds an exhaust and intake and wants some presets that are "close" to what it should be tuned to... but if you want exact its ganna need to go on a dyno.
 

Hapa

Ricky Racer - UTVUnderground Approved
Jan 15, 2009
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www.glamisdunesstorage.com
Why are people not using after market fuel controllers on these 700? On my cat every body tells me to add a fuel controller with my intake and exhaust.
 

Hapa

Ricky Racer - UTVUnderground Approved
Jan 15, 2009
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Thats true... but if your doing bigbore/stoker/bored throttle body/intake/exhaust than you should be going to a dyno shop anyhow....

Msd is good for the user that adds an exhaust and intake and wants some presets that are "close" to what it should be tuned to... but if you want exact its ganna need to go on a dyno.
I agree
 

1BDDELX

Palmdale...Come Back To Me.... - UTVUnderground Ap
Jan 29, 2009
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Palmdale, Ca
Thats true... but if your doing bigbore/stoker/bored throttle body/intake/exhaust than you should be going to a dyno shop anyhow....

Msd is good for the user that adds an exhaust and intake and wants some presets that are "close" to what it should be tuned to... but if you want exact its ganna need to go on a dyno.
Yes but the average Joe isnt doing that. The majority just put some bolt on parts on and call it good. There are alot of posts out there that say the Dynatek can't put out enough fuel with a few bolt ons and cam. Thats why Im suggesting the MSD or VDI to people in the market. I myself don't have access to a dyno so I just get out the trusty LM-1 for AFR and tune it properly and hit the gas and feel it go.
 

1BDDELX

Palmdale...Come Back To Me.... - UTVUnderground Ap
Jan 29, 2009
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Palmdale, Ca
Why are people not using after market fuel controllers on these 700? On my cat every body tells me to add a fuel controller with my intake and exhaust.
I think people are just taking a chance and adding some performance mods without the thought of fuel. Alot of people have cdi/ecu and intake and exhaust and they are probably having boiler over issues due to being way too lean. My rhino I did a bunch of bolt ons and never checked the AFR, it used to boil over and ever since I tuned it correctly, I have never had anymore boil over issues.
 

Mopar

Addicted - UTVUnderground Approved
Jan 15, 2009
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Bako So Cal
Why are people not using after market fuel controllers on these 700? On my cat every body tells me to add a fuel controller with my intake and exhaust.
Im currently running a fuel controller... but they are only necessary when you arent running an aftermarket ECU
 

KJSmith84

Banned Por Vida
Jan 15, 2009
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somewhere up my own ...
ahhhhh!!! I know guys I am still waiting myself- we are at the mercy of the dyno guy- he has been doing countless testing and on the phone with lyle figureing it all out and making sure it is at 100%. hopefully soon- but hell I have been saying that for two months now!!! lol so IDK
 

rjv

RJV n' NC - UTVUnderground Approved
Feb 2, 2009
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I have the msd, sheave, unifilter, and exhaust tip. I would like to get a muzzy exhaust, it's a nice gain. The msd is very simple to adjust if you have a laptop. A data logging air/fuel ratio gauge is great for tuning. Just go make a run and come back a view it, like a dyno with out the hp numbers.
 
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