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stock ignition, no limiter...
I am thinking its a combination of a few small things, I am gonna start with a tad more timing just to amuse myself, then look at intakes... if I gain anything with intakes I may switch back to stock heads, I used the Merlin back when because they were basically freee and new, I am looking foir my casting numbers still so I can post em... I swear they were not huge... I probably would not have used em then... |
Originally Posted by JTeam
(Post 3684205)
The 420's in my 311 came with the Weiand single planes which rotted out after two years. I replaced them with dual planes with a brass insert in the thermostat housing and never noticed a bit of difference in performance. Boat ran at 5200 with both.
Originally Posted by Full Force
(Post 3684743)
I run 34 degrees timing now... with 21P props I was spinning 5000, so I would have to use 19-20P props to see 5200, no boat I ever heard of with these engines spin that small a prop, I have an issue to resolve..
My TRS liked Mercury 25P Quicksilver 3 blades (non+Mirages) with my 420's. I bought a pair of Spinelli round ear props from dreamer a few years back. He said that they were 26's but they are more a 23. They are loose and fast. I spin them to about 6200. If you would like to give them a try I would let you borrow them. |
Originally Posted by Rookie
(Post 3684779)
There you have it. Like I and others have stated the 420 came with a single and dual. I don't believe the 15-30lb/ft is not going to give you 400Rpm.
What are the brand props you are running? Have you ran an 8' straight edge down your hull to check for hook? My TRS liked Mercury 25P Quicksilver 3 blades (non+Mirages) with my 420's. I bought a pair of Spinelli round ear props from dreamer a few years back. He said that they were 26's but they are more a 23. They are loose and fast. I spin them to about 6200. If you would like to give them a try I would let you borrow them. I woiyuld be interested in trying props once I play with stupid stuff, I really need to just dial it in best I can, once the bat ran good a couple years ago I decided to leave it alone and enjoy since first 2 years SUCKED.... lol |
40 degrees timing and race fuel....!!! LOL
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Originally Posted by Full Force
(Post 3684781)
1/4-3/8" maybe..??
I woiyuld be interested in trying props once I play with stupid stuff, I really need to just dial it in best I can, once the bat ran good a couple years ago I decided to leave it alone and enjoy since first 2 years SUCKED.... lol I have a friend that lives in Luna Pier. He is back and forth to Grand Rapids often. Just give me the word and I will put them in his truck for ya and you can pick them up from him. |
Originally Posted by Rookie
(Post 3684787)
That would be a lot of hook.
I have a friend that lives in Luna Pier. He is back and forth to Grand Rapids often. Just give me the word and I will put them in his truck for ya and you can pick them up from him. |
I'm no expert on hook, but I sanded out a 1/16"-1/8" of mine a couple of years ago and it loosened the boat up quite a bit. I just finished filling in the rest and now going to shoot gel over in the next week. The little bit of hook killed my bow lift.
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what is runner size on stock 420 heads?? anyone know FOR SURE??
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Found my paperwork....
what I wrote down.... Merlin 91 1-043 D25 thats the markings I found... Some say 345CC runner...some say smaller 320cc... still not sure.. UGH!! if the stock Merc stuff is around 320 would 25CC kill it that bad?? |
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