Mercruiser 420's single plane or dual plane??
05-11-2012, 09:49 AM
#42
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I don't mind buying other heads over winter..at that point probably ly do edelbrock or afr and convert to roller cams... my thing is I wanna mess with it while I can water test to see where I'm at... spend this summer to determine what I need to do...pull motors over winter.. I do all my own work including assembling heads.. I can freshened stickers easily at least for testing.g purposes.. not a big deal to rip off heads one weekend.. merchant used the rectangle ports on these engines to begin with...don't see why I can't use stock 420 heads that it had before.. Idknt wanna get into a crazy project during the season...
I wanna try a few things like maybe intakes....a tad more timing... Carb sspacers... just to see even with these heads if anything changes.. when winter comes I am all about redoing the engines.. I don't wanna toss too much HP at it as this boat is only gonna go so fast anyway.. 70-72 would be a sweet spot for it to me
I wanna try a few things like maybe intakes....a tad more timing... Carb sspacers... just to see even with these heads if anything changes.. when winter comes I am all about redoing the engines.. I don't wanna toss too much HP at it as this boat is only gonna go so fast anyway.. 70-72 would be a sweet spot for it to me
05-11-2012, 09:54 AM
#44
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i have posted this before but here is a good combo that has worked great for me
Dart 308's (box stock) they are even the Summit ones says iron eagle in the valve cover
Comp cam XM270H
Air Gap intake
HP 500 carb
Here is the dyno sheet with my manifolds done two months ago. the first time it was dynod with IMCO powerflows they were worth 7HP and 10LBS of TQ
Dart 308's (box stock) they are even the Summit ones says iron eagle in the valve cover
Comp cam XM270H
Air Gap intake
HP 500 carb
Here is the dyno sheet with my manifolds done two months ago. the first time it was dynod with IMCO powerflows they were worth 7HP and 10LBS of TQ
Last edited by Car Biz; 05-11-2012 at 09:57 AM.
05-11-2012, 09:26 PM
#48
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I talked to DEan Gellner today, he also said it sounds like I have the bigger heads... it's nice to have a local builder to offer help...
I will pull engines this winter I think and pout a smaller Aluminum head and probably roller cams... then they shoud be where they are supposed to be...
I will pull engines this winter I think and pout a smaller Aluminum head and probably roller cams... then they shoud be where they are supposed to be...
