Originally Posted by
mjealey
Hey guys, I have a Plus-4btt that has been absolutely bullet proof and been running fine for about 4 straight weekends until yesterday. I am running A Werks #6 plug in it with the stock Mugen clutch with the same OFNA 086 pipe I have been running this combo for 2 months. I have about 4 gallons on it. I was 4 minutes into the second 5 minute qualifier. I really have not touched the needles besides an hour here and there on the HSN each weekend and no flameouts over the last 2 months. The track had a long stretch and we twist the motors pretty good but all of a sudden the thing will die as soon as I let off the gas at the end of the straight 4 minutes into the heat. Motor was running perfect, nice and crisp, and only about 255 when i temped it.
I richened the top up a little bit, set it down to get 1 last lap in, made the whole 40 sec. lap and once again at the end of the stretch same thing when I let off the gas it just dies.
Repleced the plug and richened the LSN and increased idle gap, did the same thing in the 3 heat except earlier and in the 1st lap. Only dies at the end of the straight from being wide open for a good 3 to 4 seconds and then letting off to make sweeper curve? Idles fine, sounds great but keeps dying? I did not check it at the track, but maybe guessing front bearing? Need to tear into it tonight or tomorrow any ideas? We tuned on it the whole 3rd qualifier and the same thing no matter what we did. Also tried a #5 (hot) plufg and still did it?
Any ideas besides bearing or what would cause it to die after wide open throttle would help?
about a month ago, a friend of mine had the same issue with his nova. It seemed to run good and idle good but flamed at the end of the straight. He just changed the front bearing so he knew that was fine. Changed the glow plug from a nova 6 to o.s p4. Fixed it, ran awesome. Some say that it will harm the head button but he hasnt had problems and the engine is just more reliable. Last week we raced at gas champs where he helped out some others with nova 4btt's that had flame out problems all weekend. Changed to p4's and they ran good and didnt flame. something to try.