Air box mod

[wavemaster]

Thanks guys, I will look into it before the airbox mod.

 

[cannondale27]

Peak torque is at 8000 rpm on this engine stock, if you clutch for torque it'll be slow. Peak hp is at 8600, if you clutch for peak hp it'll be slow, I'd be looking for the most hp at 8900-9000 rpm where the engine needs to run

Yup and if you do the mods even just silencer you are leaving power behind with stock rev limiter.

 

[Studroes144]

Yup and if you do the mods even just silencer you are leaving power behind with stock rev limiter.

It seems that way, I think a huge limiting factor is that rev limiter, my viper always ran awesome right in the 9000 rpm range, but any fluctuation in traction or a bump on the trail and the engine hits the rev limiter it just kills momentum. Sure hp numbers are good, but the viper needs to really rev to run fast.

 

[Kerrdog569]

The PCV doesn't allow you to raise the rev limiter does it?

 

[MrSled]

The PCV doesn't allow you to raise the rev limiter does it?

It does not... that would only be EVOs reflash that would help you.

 

[stingray719]

Will most airbox/can mods require s fuel controller? They don't usually talk about it in these tests.

I have a MBRP trail can coming and like the idea of the airbox mod but don't really want to be adding a controller if I can help it.

Average riding elevation would probably be 1000 feet.

Where I ride I get away without a controller, but low altitude guys with air box mod and can may need one. In this thread http://www.ty4stroke.com/threads/sr-viper-hi-flow-intake-kit.126046/page-3#post-1158733 Ulmer says he has a Power Commander FC for sale for $249.00 and I would be looking at that for low altitude if you have Air Box Mod, and Can. I run my Air Box Mod on the girlfriends Viper without a can and it runs so well I may not put a can on it.

 

[shadow44]

By my estimation, the runs are as follows:

132 HP stock

137 HP air box

142.5 HP can

144 HP can and intake

So 12 HP total gain yet the flyer says 22 HP gain

Apparently they are looking at a max gain versus peak to peak rating?

You are correct, it is misleading if you're thinking about peak gains..it does say 22 hp gain and its is true, it gains 22hp in the midrange, about 7500 rpm. I went off the actual dyno sheets from DTR. Peak was 7 hp and midrange was 22hp....great gains IMO

 

[TD Max]

You are correct, it is misleading if you're thinking about peak gains..it does say 22 hp gain and its is true, it gains 22hp in the midrange, about 7500 rpm. I went off the actual dyno sheets from DTR. Peak was 7 hp and midrange was 22hp....great gains IMO

It's kind of like Gale Banks marketing strategy. Back in the early days of diesel performance so many guys bought Banks stuff with +155HP claims only to be humbled at a dyno event by a guy running an underrated 90HP module rated peak to peak. To me if I have 132HP and add a mod with a claimed 22HP I expect to have 154HP.

My issue is that the clutching does not use these RPM's at all at WOT. At light throttle cruise it will be in that range, but pin it and it should sweep through in the blink of an eye. Those mid range gains do help response, but it's not like we are sweeping through a gear.

 

[jonlafon1]

It seems that way, I think a huge limiting factor is that rev limiter, my viper always ran awesome right in the 9000 rpm range, but any fluctuation in traction or a bump on the trail and the engine hits the rev limiter it just kills momentum. Sure hp numbers are good, but the viper needs to really rev to run fast.

Anyone know if the reflash will increase the rev limiter?? I have heard RUMORS of these reflashes raising the Rev limiter a little?

 

[Studroes144]

The Evo flash claims they will, the yamaha ecu update I'd doubt they will but never know, that'd be sweet if they did

 

[stingray719]

Anyone know if the reflash will increase the rev limiter?? I have heard RUMORS of these reflashes raising the Rev limiter a little?

EVO flash raises the limiter.

 

[jonlafon1]

EVO flash raises the limiter.

What I have heard is the FACTORY reflash from cat/yami WILL bump the rev limiter a touch.. Sorry for the confusion.. Not saying this is right - just what I heard

 

[Kerrdog569]

It does not... that would only be EVOs reflash that would help you.

I thought so thanks