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Pretty standard stuff. About the same numbers Greg Coen or HQ get from a Marelli EFI 95.

The operative detail here is 2001 Road Glide. Sure would have liked to see the dyno chart and the fuel curve, the fuel curve in particular, for a very good reason.
 

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Discussion Starter #3
Are you expecting the numbers to be fudged on the fuel curve? I had read in another article on Carl's that they use a Dynojet 250 dyno and it's more resistant to tampering.
 

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No, I didn't say that. They are a pretty big name company and it wouldn't be too smart to make incorrect statements. I'm thinking more along the lines of what is not said, as is often the case with almost all companies.

In my experience it is extremely difficult if not impossible to deliver enough fuel with stock injectors and just a reflash and a PC, to maintain the curve anywhere near 13 or 13.5 : 1 at high rpm on a 95 incher with flowed heads, but to some extent it varies from bike to bike. I can see it with altered system pressures, but there is no mention of such parts (or modified injectors) in the kit.

When it comes to fudging or not fudging dyno numbers, there is more then one way to skin a cat. LOL
 

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Discussion Starter #5
Ahh...I'm on the same page now...I think. I am not familiar with EFI and assumed that when they increased the size of the TB that it was like increasing the size of a carb for a increased flowed head.

IronWorks has an article (Nov 2001) about aTC88 ElectraGlide, carburated 2 1/16 S&S Super G, but is does not have any charts with it. It also mentions in a side bar that replacing the S&S with their Typhoon will up HP to 105.7.
 

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No, the bored throttle body flows more AIR then a stock one. Doesn't do a thing for fuel.
On an EFI bike fuel delivery depends on injector flow cross section, fuel pressure and dwell time in ms. Everything else is totally irrelevant.
 

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Discussion Starter #7
Okay, can you easily increase the injector size? Or is that even an option? I'm guessing if you can, you're back to the dyno and massaging the map to the EFI.

I thought one of the articles, I'll have to look again, claimed that the stock heads flow around 120CFM and that the TC88 is much better suited to an increase in flow of which they are making the head flow 160CFM. Also, if you increase the displacement, don't you require increased air flow to the chamber. Up the cubic inches and you have to up the air/fuel flow?

Just trying to get this straight. :)

Dave
 

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The quick answer is no. There used to be high flow injectors available, but todays injectors are what they used to offer as high flow injectors. It is much cheaper to play with pressure.
There are a number of things that can be done, but it is not really within the scope or capabilities of what motorcycle wrenches or dealer shops would do.
There are a handful of companies in the country that specialize in this sort of thing. If you want to understand this better maybe reading thru THIS site would help, but it is a waste of time unless you have the capability to build your own fuel maps.


As far as flow you can write a book and end up where you started. Sure increased displacement requires a higher VOLUME of air at the same rpm. A CFM # only has meaning when it is referenced to a realistic and constant pressure drop, and a larger flow capability is not necessarily better in all cases. Flow velocity and quality are at least equally if not more important. It really depends on what you are trying to build and your normal recreational rider is not going to spend the money it takes.
 

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Discussion Starter #9
Good info Hippo! :) I like that kind of stuff, but it always make me want more. Got any other good references? Web sites? Books?

Dave
 

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To some degree it depends on what languages you are fluent in other then english. Presumably you speak japanese, but I don't so I have no idea what may be available there. The best funded engine research these days is done in F1, in Germany and Italy (other then maybe Japan and now Renault in France)
They don't tell you everything, but being one generation behind these guys will beat most others. You just have to find what is applicable to the world of Harley and what isn't.

It also depends at what level you want the info. You can get anything from Ricardo to the V-twin tuners handbooks, but written info, unless it is basic research, is obsolete by the time it is eventually published.
The most up to date written source in english are SAE papers.

THIS is one of the sharper guys in the US.

These days almost ALL technical information is equally available to all, it just comes down to differerences in philosophy, money and what you do with it.

You can find most anything you want to research with a good search engine like THIS
 

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On a very basic level THIS site has a lot of Harley related information. Some of it is a couple of years behind the eight ball, but much of it still applies if not taken too literally. Might keep you busy until you get back home and actually ride the thing. LOL
 

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Discussion Starter #13
I'll be busy with all this for a while. :)

I like Dogpile dot com for a search engine, it uses a 12 or so other search engines. Like Sherlock on the Mac.

Thanks for the info.

Dave
 

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VSS exhaust

Hippo:

I read the link on the VVS. It looked very promising. Do you know anything about this product other than what was on the site? I can't seem to find the product specs or advailability.
It looked like the possibility of a very quiet bike when riding normal and then letting it breath when you want it to.
Thanks
 

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THIS is how you order them.


There is only so much I can tell you about them, as I have only done two engines with them. I think the really major gains could come building outside the envelope you normally would for the street and use them to bring the engine back to where drivability doesn't suffer much. As of now I would be hesitant to use them on other then street engines.
It might be a while until I have the opportunity to find out more, as with the current economy the fellows that usually finance fishing expeditions have turned pretty conservative.
 

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VSS

Hippo,

The info I wanted was about the other toy listed. The thing I was interested in was about an insert in the exhaust. It appeared to be a pressure sensitive release valve working with the supertrapp muffler. The other info is interesting but beyond my ability to play with.
Thanks.
Duece
 

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Hippo: I read the link on the VVS <snip>

Oh, well. No, have not played with the VSS

It looks like the development was done in Germany and the principle is the same as the one used in the EXUP valves used on some sport bikes to broaden the powerband, except controlled by backpressure.

It looks like the WhiTek boys may have gotten in on it to suplement their fully programmable EFI, but both these things are working in the same direction.

The contact information for WhiTek is HERE
 

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vss

Hippo
I e-mailed fastbikech and they said their stuff was totally experimental. They made 200 units and is seems they hade problems with heat.They were all melting down. Starting to make them out os stainless now but only have one on them. It is for testing only in Germany.
Sound like a good idea!!!
Thanks for finding things like this. You never know when you might find something new that works great.
 

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There are a lot of these seemingly off the wall things going on in Germany, Italy and Sweden, they seem to have a knack for thinking way outside of the conventional, and the funds to follow up, maybe because of the large number of small shops that deal with cutting edge motorsports technology. Most of the information is not available in english, but you never know when one of these moonshots is going to pay off.
 
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