yes, it would have at least let you know you're in the ball park as far as fuel is concerned. The beauty of an 02 sensor, is not only does it tell you your jetting or ecm tune, it will tell you if your fuel supply is working also. Like the OP's deal for example, could have been running out of fuel on the top end from something like too small a pump, too small a tank pickup, things like that. Not sure if Baja was one to use a decent size diameter pickup in their fuel tanks.

Either way, the damage is done. Need to go back to square one.

I'm still trying to decide whether to let them have another shot at it or take it elsewhere. Boyd's Machine was the builder and they had ran it on the dyno, mostly because I wanted them to find any issues before it got back to me, at least I was hoping for that. I'll be tearing it down hopefully in the next week or two. He wants me to drain the fuel bowls as he thinks there may be a water contamination issue. One issue I have is from the beginning they really didn't give me a good solid feeling that they were comfortable doing a procharged engine, I'm not real sure if the timing was done correctly for it. I'm at the very least already expecting new pistons. Heads are stock cast so I'm hoping things may have faired better for them, time will tell.

The plugs were pulled and checked by the builder as it was ran on the dyno and also had wideband #'s on the dyno sheet. I had checked them when I installed it (had to replace one I broke putting the headers on) and they looked good then but I questioned them about the plugs not being right then and they assured me they were, now they say they were the wrong type and wrong heat. I had also checked them after first starting it prior to taking it out the first time.

I have used projected tip plugs for years upon recommendation from a Champion rep.....if you have clearance between plug tip and piston. Champion told me the plug tip is cooled by the incoming charge. You want the tip in the chamber for better combustion. My turbo charged Mazdaspeed six and Subaru's all came with extended tips from the factory, running 17 lb boost. I have run them in all my Procharged (13 lb boost) engines never a problem.
Randy

Its always "bad fuel" when this stuff happens lol.

Can you post up the dyno sheets from them? Also, what part # on the plugs

[QUOTE=tajinate;4210783] Boyd's Machine was the builder


In Norman, OK

I saw your boat at the dock up in Traverse City back in august on that fun run. I was digging that whole intercooler setup you got going there!

I was always told to stay away from projected tip plugs in forced induction stuff, and if used, the timing lead should be compensated for them. Got this from the champion catalog

J-Gap Projected Tip
This gap style positions the spark an additional
1
⁄
8
inch into the chamber and, providing there is sufficient clearance to valves
and piston, provides the ultimate in performance. Initiating the flame front
closer to the piston top at a given spark has the same effect as advancing
the timing. Therefore, maximum timing may be reduced, which helps to
reduce detonation and octane requirement and still provides good part
throttle response. For normally aspirated engines only; not recommended
for turbocharged, supercharged, nitrous oxide or nitro burners.

https://www.pegasusautoracing.com/2014/066.pdf

I can pull the dyno sheets tonight, plugs are Champion RV9YC, was told to switch them to a V63C.

So they suggested going from a projected tip RV9YC, to a non projected tip V63C, which is also about 2 heat ranges colder and more inline with what most supercharged engines run including the mercury racing ones. Which makes sense. But sounds like its too late anyhow.

While some may disagree, I would prefer to run the latter plug (v63c, AR134, NGK 5673-8, MR41T, ) than the projected tip stock heat range spark plug, in a forced induction iron headed engine. Just my opinion.

Widebands are great I have one on my boat. But there is alot of things they don't tell you... I bought the latest and greatest Edelbrock single plane for my latest build. Suppose to have great fuel distribution better than anything else out there and at $469 I would think it should be perfect. What the wideband didn't tell me is that the new intake has the same piss poor fuel distribution as everything else maybe a little worse. Rich in the corners lean in the middle go figure. What they also don't tell me is what heat range plug the motor wants or ignition timing. When I got the heat range, timing and fuel right. I learned I didn't have enough octane. Then I started mixing 20% race fuel. What I ended up with my setup was two different heat range plugs in the motor , race fuel pump gas mix and a semi reverse cooled cooling system. But she's perfect now. Hold it wide open till it runs out of gas...