Oxigenated fuel(good or bad)

3 replies to this topic
  • CaptainKnobby

Posted July 17, 2007 - 10:56 AM


My suspension guy was at the track this weekend and said he had some VP oxigenated fuel that he got at a good price,He said he got it at $10.00 a gallon. I bought 2 and 1/2 gallons and he told me to mix it with 2 1/2 93 octane. The gas was a green color and after useing it this past weekend I noticed when I came back in from a run the gas was bubbleing in the vent hose on top of the gas cap. The gas I was useing before which was cam 2 did not do this to my memory. I couldnt really tell a difference in the performace if it made any,could this type of gas mixed with 93 cause problems with stalling?

  • grayracer513

Posted July 17, 2007 - 11:07 AM


Oxygenated fuel adds oxygen to the combustion process, and this needs to be compensated for by increasing the richness of the fuel mix (bigger main jet). How much will vary. If you pilot circuit ends up lean because of using the fuel, it could cause stalling.

Also, be aware that cerftain VP U4 fuels have been recalled:


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  • CaptainKnobby

Posted July 17, 2007 - 11:14 AM


Thanks grey!!!! I am not useing this fuel no more!!!!! back to cam 2

  • Ga426owner

Posted July 17, 2007 - 11:33 AM


Thanks grey!!!! I am not useing this fuel no more!!!!! back to cam 2

slow down hoss......your venting issue is not fuel related....:thumbsup:

VPU4.2 is great fuel and I would gladly use it over Cam2 anyday. You must be jetted correctly for any race fuel to get the most benefit out of it.....
If U4.2 scares you....which it should not,
Try C12 mixed 1:1 or 1:.5 with pump premium - this is great fuel but not oxygenated...Oxygenated fuel is great and VP say 6% HP increase

I am now a U4.2 user as well as a C12 user...with lots of VP history good and bad......U4 is gone, and U4.1 is recalled

research here


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