Lots of questions:
Previous engine failure was caused by a lack of attention to detail, primary issue was spring crash which broke retainer sent a valve head through a piston.
Exhaust valve contact was a combination parts improper piston pocket depth and several of the pistons in the wrong holes
Dyno information, First they are JUST NUMBERS that mean nothing unless you have several engines and combinations on the sameday same dyno same conditions...I don't race dynos because they have really bad understeer..
My goals for using an engine dyno are always to break the engine in a controlled environment.
second is to jet as reasonably close to peak performance as the dyno can provide.
After a few teething issues (which I had never seen before) we were able to start making pulls. We worked first with the 40mm carbs and 36mm chokes to get to the first numbers around 275 HP and what ever the torque number was (again just numbers to me) I did add timing all the way up to 38 degrees total after 3k and the torque really enjoyed the additional timing.
We put 45s on with the emulsion tubes and jets from the 40s since we were looking for data. 45s had 36mm chokes. With the 45 we went from 165 to 175 then 190 and back to 185 for a 20+ HP gain and a good increase of the torque distance across the board. We then went to the 40MM chokes which showed a small gain up hign but a slight dip in the area that we want to run this engine.
At this point I felt we needed to not beat on this thing any longer and get it in the car, Mark will bring the car back to Oregon City with his headed and MAP sensor setup so I can run it on the dyno jet and maximize the power curve for what he is going to use it for. I feel I can tune the dip out of the 40mm chokes with a different emulsion tube and play with the ignition curve to make this thing make more HP and Trq. That is also why I did not see any benefit in stepping up the pilot jets until we were working on drivability.
All in all this was a very long project that allowed me to build something different than my normal roadrace recipe that makes great power under 7500 RPM which will allow it to run forever if not abused.
I would run the TWM air horns on the thing as well as a Airbox and it will pop right over the 300hp mark if the number is important.. Right now this thing pulls like an old dodge diesel and sings a nice song at 7k.
Mark should be commended on his drive to get this data and share it as this was a ton of work and a ton of effort on his part.
Photos are a modified carbon air box and air horns I build for a Vintage L24 that makes very solid HP.