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what I have heard, depending on the bike which one it likes. there are threads already outlining differences on certain bikes and what has worked or not. good luck...
 

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6K You asked...

<<<< E-Series or Thunderheader?

What are the facts? >>>>
____________________

(Until Hippo, or somebody that actually knows what he's talking about responds, you can chew on this)

That's a very vague question. Too Vague.

The WB E-series can be 'adjusted' for exhaust flow, changing the reversion waves or back pressure, and can be dialed in to a particular application. That's desirable with some pickie EFI systems like the Delphi, or it can be adjusted for engine mods with a carbed Bike. I don't know how they sound (obviously the more disc', the larger the flow, and the louder the report).

Thunder Header does put out good dyno numbers from what I've seen.

General concensous is Thunder Header Thundercones slip-ons do not perform well with the Delphi FI. Something to do with the reversion waves, I think...
 

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Hey Hippo!

So to be clear, will the "2:1 Thunder Headers" *work* on a delphi injected bagger?

I know they will bolt up, but will it run decent?
 

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I have always liked the TH but on the Delphi bikes it just seems like pipes with more backpressure work better.
I think it also has something to do with how big the engine actually is, not only in cubic inches but also on cam.
On the Delphi bikes I prefer the E pipe / Supertrapp type of pipes, but on some big engines you seem to find good numbers with the ProPipe.
Could well be that some cams like some pipes.
 

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HIPPO,

Would a Thunderheader be a substantial power upgrade to a 95" hi-comp Twin Cam running SE Heads, SE 257s, roller rockers, SE 6200 RPM race ign., Keihin with Thunderslide & 48 slow/195 main?

I'm currently running Samson Street Sweepers w/Torque Cones. My belief is that some more back pressure is in order. I'm currently working on a baffle design for fitment in the Street Sweepers.

What pipe do you recomend for optimization of this particular build? The bike runs great as is but I think those pretty 2 1/4" pipes are hurting the potential of the engines capabilities.
 

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TH always worked well on carbureted bikes as well as the ProPipe, the disc two into ones also work on the carb bikes, basically just pick the one you like based on looks and noise level.

I would lose the Thunderslide kit, but that's personal preference. The Mikuni also works very well if you know how to dial it in.
 

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That was fast! Thanks...

I've read some of your other posts touting the disadvantage of Thunderslide kits. I don't think anything could work much better from a driveability standpoint. Nary a cough in 2500 miles! I just can't bring myself to take the Dremel to the fins of my SEs to allow fitment of a Mikuni. I tweeked the CV myself and like I said, it's spot on. No experience w/Mikuni tuning even though I did download and print the tuning manual from thier site just in case.

Can you point out any particular negatives regarding the Thunderslide? Throttle response is acceptable for a CV which the major consensus say is a little soft on the hit. Circuit transition is smooth and I've yet to run out of top end. Pulls hard to 110 anyway... I tend to get a little nervous at triple digit speeds.

Do you suggest going back to the original style slide and spring?
 

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If you are happy run it, no big deal.
It is possible that the lighter slide might improve throttle response marginally, but the lighter spring and the larger vacuum port have a strong tendency to cause slide flutter.
These are not huge issues and they tend to get beat to death. Not worth it to mess with a thing you are happy with for a couple of horses.
All these opinions are based on the premise that they take place before the fact, once you paid for the parts there isn't much point to them.
 

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Thanks man,

I may now relate the choppy no load behavior, to slide flutter... I previously thought the cam profile was the culprit. Am I correct in my assumption?

Sorry about dragging this thread off topic.
 
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