madkaw

My thought on the reliefs was more of chamber matching then just clearing for pistons. Considering a mn47 head with oversized L28 pistons might be a engine to try this with. Lowering CR and clearing valves for what would be a necessary larger cam.

Found one

Wished I lived closer to some of these west coast Pickn.pull's in Newark and Redding CA , so I could just pick my own:)

Thanks for the response. I've seen some videos of your method. Not sure what the limit is as far as cam numbers that would need this kind of clearance. I don't think my 490/290 cam will be a problem, but I know it's a matter of measuring for sure.

Are the L28 flatops thick enough to cut reliefs ? Like to do some combustion chamber matching and tried searching and couldn't find anything.

Same number- different combustion chamber.

New Zed, I have an option for someone to pull a mn47 for me from a yard out west, but was hoping someone already had a core laying around. Jamal, thanks for the pics, but it's the Maxima head I want, not the zx. Always liked doing business with you, maybe next time.

So I am looking at this solution for my set-up. Running MS3 with LS1 coils on an original 71 current tach. The directions from Turbo6inKY above says to hook the black/white stripe up to a 12 volt ignition source. But originally the black/white going to the tach was hooked to a 12volt ignition source, so why not use this right?. Maybe over thinking this, but want to be sure.

Jamal , I'll take pics please and any history on the head. Could you email me S_finnerty1018@comcast.net Thank

I found a few maxima 's in the Pickn.pull site and they are all in CA or WA

Been looking- believe me. They always seem to end up on your side of the country.

Looking for something I can tailor for my build. Sounds nice but not what I am looking for.

The motor sounded awesome before the fire- sorry for the loss.

Looking for a n-47 that came on the early maximas-81-84. Bare or loaded, doesn't matter.

Thanks for taking the time and doing the dyno runs during all the changes. We have dyno numbers all over the website, but not much of a direct comparison after changes on the same motor and dyno. It would interesting to see what changes will happen as you let the motor breathe with bigger straws;) I hadn't notice before that you were only running 40's, or do I have that right? You know Rebello big numbers straw through some 45's or even 50's, which is probably needed.

It seems contradictory that you are shooting for performance at 2000 rpm with main airs as big as you have them. I think IMHO that you are way too big on the main airs and it's throwing off your tuning. Running that big of mains and then diluting the mix with that big of main airs seems self defeating. Since you have had other issues(cam timing), maybe start back on the small side. Remember the smaller the main air jets the richer the main jet mix. How about something completely different like 155 mains and 180 main airs and see what that yeilds? Once again I'm not sure you are going to get a street tune with that big of cam. I wouldn't even tune for WOT under 3000 rpm. That puts you right in the middle of the transition issue with triples and it also puts you in timing curve issues. I would tune for WOT and cruise and idle. Idle for easy starts, cruise to keep plugs clean, and WOT for WOT. Staring at the Wide Band during driving could lead to insanity and a bad accident-lol

Like said, if it's well done I can appreciate it regardless of taste. Thanks for sharing

That's a lot to be off with a big cam. I guess take the good with the bad here. I always wonder why more folks don't degree their cams since it has a big effect on performance.

I have a complete set myself:)

I believe Jon was saying that in most cases 40 pump nozzles are plenty big enough for accelerating, but the pilot jets cam help a lot with hesitation. Go bigger on the pilots before messing with the pumps. If you read this thread you will read that I tried many options to cure transition issues. The changing of pump sizes and setting did nothing. Now if yours are not working then that's a different story.

And thanks again for sharing this process. I worked a short time as a machine operator/machinist in Fort Walton Beach FL for aero tech or something like that where we repaired jet engine cases. I really enjoyed doing the machine work even though it is primitive(operating a 42" vertical lathe ) compared to CNC creations like this.

I am jealous of your expertise in machining(creating)!

So much to do so little time

Exactly

Todd at Wolf Creek had me remove the cover and rest it against something and measure the distance between the cover and the top of the float =12mm Not sure is 44's are different then 40's