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Best Performance With 1250 Big Bore kit?

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  #31  
Old 12-31-2017, 08:12 PM
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Originally Posted by Madnss
“Is the 1250 worth the extra money?
A 1250 is about 4% more displacement than a 1200. Assuming displacement is limiting the power of the motor, 4% more displacement would yield 4% more power. In reality, it generally comes out a little more than that, on the order of 6-7%, because there's an increase in compression that comes with it when comparing to a stock 1200. Also, the larger bore unshrouds the valves a bit more and enhances breathing.

So is 6-7% more power worth the cost of the kit? On an otherwise stock 1200, probably not. You can find more power than that with simple pipe and air cleaner changes. But once you've picked all the low hanging fruit, you'll quickly find that additional horsepower starts getting very expensive. At that point, a 1250 kit will be the cheapest horsepower you can buy.

On an 883 that's being converted, though, the picture is quite a bit different. The incremental cost of the 1250 kit over a 1200 conversion kit is only a couple hundred dollars or less. That makes the decision quite a bit easier. Toss in the fact that Sledge Hammer cylinders and pistons are much higher quality pieces than the stock type conversion pieces and it becomes a no-brainer.”

FYI: It’s quoted because I didn’t write it, but I feel it’s great information about a 1250/1275 set up over a standard 1200
You you definitely have some valid points there and I'm not going to knock them, 6 7% 12 to 1250 yes I agree and there's other ways of getting that. Now your talking like a true supporter of where performance goes and we all understand that there's different ways of getting performance. There's also other shops out there that can get you the same outcome. Some of us do foolishly spend to get that to 3% cuz you know it does make a difference but we're in all honesty bragging. Been there done that but I still enjoy what I had and it doesn't matter what I spend to get there I still love it.
 
  #32  
Old 12-31-2017, 11:26 PM
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Originally Posted by 98hotrodfatboy
You you definitely have some valid points there and I'm not going to knock them, 6 7% 12 to 1250 yes I agree and there's other ways of getting that. Now your talking like a true supporter of where performance goes and we all understand that there's different ways of getting performance. There's also other shops out there that can get you the same outcome. Some of us do foolishly spend to get that to 3% cuz you know it does make a difference but we're in all honesty bragging. Been there done that but I still enjoy what I had and it doesn't matter what I spend to get there I still love it.
Heck ya man! Happy new year!

Just to be clear, not my points, I didn’t write the paragraph, but I firmly agree.
 
  #33  
Old 12-31-2017, 11:32 PM
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There's also other shops out there that can get you the same outcome
I firmly believe there are shops out there to get a nice hard running sporty. Actually, a lot of shops out there. But, as far as top shelf hot rod hard running Xl street 1250s, I feel the list gets very small.

I base my knowledge a pinch on dyno sheets and a lot more on street legal “Hot street” xl’s at the drag strip. Anyhow, again, cheers mate!
 
  #34  
Old 01-01-2018, 01:32 AM
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Cheers, happy New year.
 
  #35  
Old 01-05-2018, 11:51 PM
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Hammer 1275, add some cams and headwork. Boom! A nice running Xl that has some snort !
 
  #36  
Old 01-13-2018, 05:30 AM
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amazing how much gum flapping when on in this thread from twin cam folks acting like a sporty evo is a twin cam.

@op: what did you end up doing?
 
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