Fuel Consumption Culprit Found

[irish2themax]

Way back when, I was having trouble with backfiring and "chugging". This was before they were offering the mod that fixed this issue. Rather than buying a Juicebox, I spoke with my dealer (who has since gone out of business) and they suggested installing a fuel pressure regulator.

Since then, I have been VERY displeased with my fuel consumption (barely getting over 21 mpg). I had always suspected that I was running lean but, on my trip to Gatlinburg, it was confirmed. Altonk was riding behind me and he said that every time I downshifted, flames would shoot out of my exhaust.

Put the beast in for my DPS mod and had Hanover Motorsports (my new dealer whom I really like) check it out. They said that the Spyder is supposed to run with a fuel pressure of 51 PSI. I was running at 85!!! So they leaned it out. Can't wait to get it back to see how it affected my fuel consumption.

 

[Bob Denman]

Nice catch by you guys! :thumbup: Let us know what your mileage is now!

 

[SpyderWolf]

Good catch by the Altonk and the new dealer, but you actually have it backwards. With a higher fuel pressure you were running too rich, not lean. The extra fuel that was not burned upon compression was being burned in the exhaust, thus causing the flame out. It may not be a bad idea to have the baffle on your exhaust can checked at this point as well, as the flames may help burn that out faster.

 

[Firefly]

Way back when, I was having trouble with backfiring and "chugging". This was before they were offering the mod that fixed this issue. Rather than buying a Juicebox, I spoke with my dealer (who has since gone out of business) and they suggested installing a fuel pressure regulator.

Since then, I have been VERY displeased with my fuel consumption (barely getting over 21 mpg). I had always suspected that I was running lean but, on my trip to Gatlinburg, it was confirmed. Altonk was riding behind me and he said that every time I downshifted, flames would shoot out of my exhaust.

Put the beast in for my DPS mod and had Hanover Motorsports (my new dealer whom I really like) check it out. They said that the Spyder is supposed to run with a fuel pressure of 51 PSI. I was running at 85!!! So they leaned it out. Can't wait to get it back to see how it affected my fuel consumption.

So I'm assuming you have the Evoluzione fuel pressure mod ?

I have this unit and it's very important to have a proper gauge to read the fuel pressure. 85 would for sure be WAY too high. Highest I ran mine was around 64. Down to around 54 right now and have good power and fuel mpg isn't too bad. Added the JB into the mix to fine tune where I wanted fuel.

 

[pierrelogic]

Pull a spark plug too. They could be fouled running that much fuel through the engine.

 

[irish2themax]

With a higher fuel pressure you were running too rich, not lean.

You're right...I meant rich

 

[Trickie Dick]

All right, Irish. No more 100 mile per tank runs. :2thumbs:

 

[Euripedes Neves]

Gas mileage 2008 RS

Nice catch by you guys! :thumbup: Let us know what your mileage is now!

I instoll a new exaust from HMF and K&N filter and my spyder go 150 mls before enter reserve, I haved done 175 w/ 5 1/2 gls of gas. speed of 60 to 70 mls. I think is very good.:firstplace::ani29::2thumbs: