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tinman22

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not to beat a dead horse but how much is a set of flatslides again?49549FCC-BB1B-44E1-9ADF-7E4115104C8C.png
 
More than the bike is actually worth for no real performance gain at all than the bike had stock.

Read that 5 times.
 
agreed. interesting though. would make boost or nitrous more efficient/reliable/tuneable if one we're intent on going that way. I haven't herd any talk about the limits of the stock crank and cases.

probably stronger than the stock heads would flow natural. i guess there are plenty of them at or around 200 h.p.

But hey there is still a set of billet heads on ebay for $7000.

i wonder how much torque you could coax out of one before things started to go wrong.

as far as more than its worth. true enough. sometimes it's just fun to do things.

The entire racing world revolves around spending more money on something than its worth.

read Brad Mummert 5 times
 
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I’m not sure if we’re still talking about fuel injection or flat slides. If it’s fuel injection as Sean has pointed out on numerous occasions anyone can make a fuel injection system, it’s getting it to work that is the problem.
 
I was talking fuel injection. I was looking on ebay last night and came across that listing.
At first glance it looks fairly well sorted. sure flatslides are cheaper but if the bottom end could handle big power it would be worth it if you were intent on building a big power bike.

just curious what exactly are the issues with getting injection to work.65C2ACE2-A723-4072-8880-FD50ADE753BD.png
 
just curious what exactly are the issues with getting injection to work.

It's many fold. The Vmax was never intended to be fuel injected. It doesn't have the proper computer control systems to do it.

Now, you can add all that on, but then you are going to have to do the work of an entire team of engineers programming your own custom system that knows how much vacuum at every RPM requires how much gas from each injector.

And that's just for starters. You haven't even gotten into the timing curve yet.

And in the end you're really not going to get that much if anything out of it. So it's a matter once again of "what's the point"?

If you have a lot of money, are very good at math and have nothing better to do, go for it. If you're looking for a bolt on system, you're looking up the ass of a dead dog.
 
It's many fold. The Vmax was never intended to be fuel injected. It doesn't have the proper computer control systems to do it.

Now, you can add all that on, but then you are going to have to do the work of an entire team of engineers programming your own custom system that knows how much vacuum at every RPM requires how much gas from each injector.

And that's just for starters. You haven't even gotten into the timing curve yet.

And in the end you're really not going to get that much if anything out of it. So it's a matter once again of "what's the point"?

If you have a lot of money, are very good at math and have nothing better to do, go for it. If you're looking for a bolt on system, you're looking up the ass of a dead dog.

Well I have to answer this tosh.
How many engines have you added FI to @Parminio ? I've done a few. All were bare engines in road or race car chassis. You don't need complex maths, the ecu does this for you, all you do is fill in the right numbers in a map. It's quite a buzz when it starts to come together, but you do need a dyno.
And you know what, You might not gain more than 10% at the top end, but low and mid range I would expect to be streets ahead, plus mpg.
 
Well I have to answer this tosh.
How many engines have you added FI to @Parminio ?
4
I've done a few. All were bare engines in road or race car chassis. You don't need complex maths, the ecu does this for you, all you do is fill in the right numbers in a map.
Your problem: The ECU's in those kits, such as the Holley 550 efi, come with ECU's that have programs already set up for base line operations of V8's, V6's and 4 cylinder car engines. You simply fine tune it by plugging in the values you need.

There is no such kit with control module for a Vmax. You would literally have to completely program one for the Vmax from the ground up.

You're comparing apples and oranges.
 
Absolutely not. Every ecu I've used has settings for single, double, staged or individual injectors, so you can set them up for a 4 cylinder. You can either specify at order, or configure (within certain limits) the trigger you want. The best ones are 36 tooth, but you can use 4 or less, with poor response. For a vmax something on the back of the gen rotor would seem ideal.
The ecu doesn't know or care what engine it is, especially for fuel. For ignition the v4 does produce problems, hence my suggestions for using Ford edis and the vmax triggers - however, the latest spec ecus can do unneven firing, and ultimately there are only 2 events.
So you don't have to completely program anything - either spec it on order or get one that can do the odd firing v4. Not hard, and probably quite fun?
 
The main issue is odd fire and odd timing requirements. Haltech and Megasquirt both have the capability once you get the flywheel modified or add a pickup of some sort on the camshafts. The firing timing order is not simple when you are skipping a cylinder every rotation which is not the same cylinder on the next pass.
 
micro squirt works with odd fire,wasted spark,dual pickup 4cyl c.o.p. ignition. at least that what they say.

so at what point does the bottom end give out?
 
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Tossing this out in curiosity.......Maybe the answer is simple with several sensors and programmable "everything" but the V boost needs to be considered too, correct ? Would the fuel mixture or injection "shots" need to be programmed via dyno hours for many many different load (gear ratio) vs RPM cases ? Is the A/F ratio always the same as the engine RPM rises through the V boost phase at different loads? The original CV carbs do a beautiful job for this but I suppose all engines have this issue and sensors can tweak the A/F based on exhaust sniffers. Will on board sensors and computers manage these cases ?

In any case I think the ancient rule of
racing definitely applies here: You need cubic inches and/or rectangular dollars to go faster. Tens of thousands if the labor isn't free ??
 
All of that comes into play. That's why it's pointless. It's simply not worth the time, money and everything else that goes with it when you can just buy a Gen 2 and go from there.

This topic has been done to absolute death. The fact that, to date, nobody has ever done it should put it to bed as being completely not worth it.

But wanna-be pros are going to be wanna-be pros.

If anybody was going to do it, trust me, Sean Morley would have done it by now. Even to him it's just not worth the effort and this is a guy that's been one of if not THE guru's of the Vmax.
 
Never-say, "never!"

John Britten was pretty-much a one-man show, in that he chose a path that shocked the motorcycle competition world, beating the dominant factories, because he had the talent, and the vision to engineer unusual solutions to problems others approached in more-conventional fashion. A lucky few were able to afford the streetbike versions, but cancer got him, too-soon. I'll never-forget watching the two Brittens competing at Daytona International Speedway against the previously-dominant Ducatis, and watching the Brittens gap the Ducatis, at-will, wheelie-ing the length of the straight, after the infield hairpin turn. I have pics of those bikes, I took in the pits, a testimony to one-man's vision and efforts.

Speaking of Gen 1 VMaxes, look-up Herbert Katzinger, who built probably the most-capable road-course VMaxes, ever-built. Anyone who's been into Gen. 1 VMaxes for any length of time, knows they don't have a reputation as road-racing paragons of performance, to-say the least. Katzinger made so-many mods to the VMax, it probably was more-like the Dresda, the Rickman, the Seeley, or the Egli bikes, using as a basis an engine from the donor bike, and everything-else, custom. I think it was Cycle World who described how he would show-up at a track, take his VMax out, and put the Ducati superbikes to-shame, then return to the pits, and set-up to take orders for work and bikes.

Economically, the market for such a kit probably isn't strong. Obviously, it can-be done, but who wants to devote the time, knowing that the economic reward just-isn't there? Anyone capable of the work would probably be better-served by fluffing a Porsche 911 or a 2020 Corvette, as the potential customer base is larger, and better-monied.
 
Never-say, "never!"

John Britten was pretty-much a one-man show, in that he chose a path that shocked the motorcycle competition world, beating the dominant factories, because he had the talent, and the vision to engineer unusual solutions to problems others approached in more-conventional fashion. A lucky few were able to afford the streetbike versions, but cancer got him, too-soon. I'll never-forget watching the two Brittens competing at Daytona International Speedway against the previously-dominant Ducatis, and watching the Brittens gap the Ducatis, at-will, wheelie-ing the length of the straight, after the infield hairpin turn. I have pics of those bikes, I took in the pits, a testimony to one-man's vision and efforts.

Speaking of Gen 1 VMaxes, look-up Herbert Katzinger, who built probably the most-capable road-course VMaxes, ever-built. Anyone who's been into Gen. 1 VMaxes for any length of time, knows they don't have a reputation as road-racing paragons of performance, to-say the least. Katzinger made so-many mods to the VMax, it probably was more-like the Dresda, the Rickman, the Seeley, or the Egli bikes, using as a basis an engine from the donor bike, and everything-else, custom. I think it was Cycle World who described how he would show-up at a track, take his VMax out, and put the Ducati superbikes to-shame, then return to the pits, and set-up to take orders for work and bikes.

Economically, the market for such a kit probably isn't strong. Obviously, it can-be done, but who wants to devote the time, knowing that the economic reward just-isn't there? Anyone capable of the work would probably be better-served by fluffing a Porsche 911 or a 2020 Corvette, as the potential customer base is larger, and better-monied.
Nice to read a sensible post on this👍👍
 

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