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Evo engine mod question

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Old Dec 11, 2007 | 07:01 PM
  #1  
dustinw58's Avatar
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Default Evo engine mod question

I have a 96 Fatboy and I'm looking to get a little more out of it. Just wondering if bumping up the compression to around 9.5:1 or 10:1 and putting in a different cam would make a noticeable difference? Any ideas are welcome. An was wondering what price range would this fall into?
 
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Old Dec 12, 2007 | 08:15 AM
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Default RE: Evo engine mod question

A Bob Wood 6 or EV-27 set at or near 9.5 or so, a good valve job, tuned correctly, will show you about 80 hp and 90 ft/lbs, favoring the Wood grind. Fuel economy will be way, up and the smoothness of the power delivery will amaze you.
Scott
 
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Old Dec 12, 2007 | 09:01 AM
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Default RE: Evo engine mod question

For 2500/3500 $$$ put a magna--super--charger on it. Or a pro charger but they are more money then a magna.You will feel. I just put one on 3 months ago FOR A CUSTOMERon a 99 fatboy with just an ev 27 cam. on a stock motor all I have to say is holy lee S%%%%. If you have any question email me.

Super chargers work great on stock motors with low comp. evo 8-5-1 you can get boost 6/11 psi with out having to change pistons. BEST BANG FOR THE BUCK PLUS THEY LOOK GREAT.
 
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Old Dec 12, 2007 | 11:56 AM
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Default RE: Evo engine mod question

I used to do a lot of these with domed pistons (straightening up the bore helps a heap), replace the plastic breather valve with the new timing S&S breather and EV3 cam. Tighten up the quench at the same time and you will be a happy camper.I have a set of heads that will really turn it on.
 
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Old Dec 13, 2007 | 06:05 PM
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Default RE: Evo engine mod question

What kind of numbers would those setups put me at dyno wise?
 
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Old Dec 13, 2007 | 08:12 PM
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Default RE: Evo engine mod question

On a stock evo depends on boost 90/107 horse. power with good pipes.
 
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Old Dec 14, 2007 | 10:30 AM
  #7  
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Default RE: Evo engine mod question

When we weld and cnc port the heads we get a quick reving, cool running 90/90 and don't recommend much more because thay have a tendency to break the stock cases.
 
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Old Dec 14, 2007 | 11:43 AM
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Default RE: Evo engine mod question

Is that a bolt in style cam? Just wondering cause thats what I'm looking for I really don't wanna have to change all kinds of stuff in the valvetrain. An you run a dome piston with that type of a setup? How what does that put the ratio at? Is a stock starter enough or will it eat that up?
 
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Old Dec 15, 2007 | 09:11 AM
  #9  
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Default RE: Evo engine mod question

This is a bolt in cam and the 10 to 1 domed pistons will not kill your starter.
 
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Old Dec 15, 2007 | 09:24 AM
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Default RE: Evo engine mod question

Why the dome pistons? I always thought that flat tops where more efficent.
 
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