smashed electrodes.

[thesoultaker2117]

Tried that. I tried timing from 75 thousandths all the way up to 110. It actually occurred less with more timing. The motor runs strong and other than the plug issues, guys at the track know my machine when it ran, it hauled ass. Pulled off my fastest time yet at the beginning of the year. And I can only imagine the power it would have if I could figure up what this stupid little issue is.

[J-Madd]

What is your jetting? Someone that runs gas could probably help ya there if it's way off. It is for sure deto. Plug color is different with different fuels. Is the color what it should be according to VP after a WOT run?

[J-Madd]

And that sounds like a lot of timing for gas.

[thesoultaker2117]

Jetting is 170 mains. 52 pilots. Dgh needles. Only thing I really changed this year is pipes and domes. The plugs burnt a light chocolate

[thesoultaker2117]

And my jetting is about the same as other similar setups. Messed with timing and jetting both. Even tried different mixing oil. Frustration from a year that could've been better

[SlowerThanYou]

I have a tech bulletin from VP Fuels. I have primarily race with their fuels & found the bulletin to be correct for our tuning.

 

" VP "C" series racing fuels show a lean appearance on spark plugs compared to other racing fuels,"

 

" With correct jetting the plugs will look some where between a new plug to a very light gray color, if there is a yellow tint present that means your are to lean. If there is a green tint you are very lean. A spotty or solid dark gray indicated you are to rich."

 

We have ran across all these conditions & found them to be correct.

[m671054]

Does this happen on both cyl or just one?

[BANSHEE HP]

What stroke is this?

[thesoultaker2117]

Both cylinders and is a 4 mil long rod. Its your semi typical 421 cub.

[thesoultaker2117]

And thanks slower than you......that's some good info there.

[thesoultaker2117]

http://i1268.photobucket.com/albums/jj571/Thesoultaker2117/2013050395153724_zpsb3c2b611.jpg

[SlowerThanYou]

And thanks slower than you......that's some good info there.

 

I don't know if I helped out much, but I've never had light chocolate plugs on VP fuel. I think your issues are with the domes, timing or not enough octane.

[thesoultaker2117]

Would maybe bumping to c-14 help?

[SlowerThanYou]

What do you fix first, domes, timing or octane? LOL! Something is not happy & you need to get it fixed fast. It will start damaging other things, if it hasn't already.

 

If it was me, I would lower the compression. 500' is starting to stretch it out a little bit. We primarily run 1/4 mile & really notice a difference with the lower compressions.

 

If you are going to take the fuel route first, I would try C14 Plus.

[thesoultaker2117]

What do you fix first, domes, timing or octane? LOL! Something is not happy & you need to get it fixed fast. It will start damaging other things, if it hasn't already.

 

 

 

Shoot me a text.....8145058437 if ya have time

If it was me, I would lower the compression. 500' is starting to stretch it out a little bit. We primarily run 1/4 mile & really notice a difference with the lower compressions.

 

If you are going to take the fuel route first, I would try C14 Plus.