V-boost is glorified solution for bad carburetors. Funny!!!

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Opinions are different, there is nothing unusual about it. :)
It's not an opinion, man. It's a FACT.

Your entire equation is complete junk. It's not even remotely correct. I'll walk you though it since you're obviously too slow on the uptake to figure it out.

First off, you never use a ² unless it's going to represent a number too large to fill in or a variable. You don't even have a variable anywhere in that equation.

So you wrote this:

(36 sq x 145)/116)=40

There's no reason to even write 36². At all. It's absolutely moronic to do so.

36² = 1,296.

So your equation should read:

(1,296 x 145) / 116 = 40

But it doesn't. Following rules of math the equation inside parenthesis is done first. So that makes your equation turn out to be:

187,920 / 116 = 40

But it doesn't. It equals 1,620. Your ENTIRE EQUATION IS CRAP. Full stop.

You.

Are.

Wrong.
 
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Can we all agree that 40 mm carbs from ZX11(147HP) will do fine on Vmax 35mm carbs (145 HP)? 😁
 
We can all agree you're completely full of it and make things up as you go along. That's what we can agree on.

After 36 years, nobody has really come up with a better system for a Gen 1 Vmax. That tells me that the engineers got it right the first time.

Not surprisingly, they knew how to do math.
 
It's not an opinion, man. It's a FACT.

Your entire equation is complete junk. It's not even remotely correct. I'll walk you though it since you're obviously too slow
Considering you missed a few math lessons in school, I am going to "slow" down, so you will understand.
Power depends on amount of air, engine can suck in.
Amount of air depends on carb hole surface mm ² .
Are you with me so far?
Surface depends on D square
Sorry, got bored, good bye! Ask Fire medic, he knows everything! 😁
 
Considering you missed a few math lessons in school, I am going to "slow" down, so you will understand.
Says the guy that wrote a bogus, completely wrong equation.

Power depends on amount of air, engine can suck in.
No, it doesn't. It depends on a great many variables. Cam lift, duration, CID, stroke, and RPM all dictate that. Change any single one of those variables and you change the amount of mixture you can move.

Surface depends on D square

No, it doesn't. That's another moronic variable you're pulling out of your butt.

CFM is how air/fuel mixture is measured. Cubic Feet per Minute. There is no "surface" variable at all. You're measuring a 3D space, not the surface of your coffee table.

You know, it's typically best that once you've already been proven wrong to just stop talking about it. Every single post you make you look more and more ridiculously stupid.
 
Hmmm, I think we need to consider that people can have differences of opinion, even if they're wrong. Please excuse my dear Aunt Sally.

A set of 40mm carbs for one cyl head configuration isn't going to be the same thing for another. Velocity of the air/gas mix is going to be greater for a smaller diameter than it is for a greater one. There are so-many variables that engineers take into-account, each application optimizes for the intended use to-which it's put. You want big high-rpm horsepower, the low and mid-range is gonna suffer. You want strong mid-range for roll-on throttle response, the top-end will be sacrificed. The VBoost allows a top-end fuel supply, with low-and mid-range torque from the higher-velocity smaller carburetor venturis. It results in lower-end torque and high-end horsepower.

Jerry Branch when working on the Harley-Davidson KR and KRTT factory racers, which were 1960's era flathead engines, discovered that the old hop-up trick of "throw in some bigger valves there, Earl, that will do-it!" in-fact, didn't do it, where the Harley-Davidson flathead powerplant was concerned. Jerry Branch ran smaller valves, to speed-up the gas/air mix flow, and instead of the 'polished' intake tracts, which look so-pretty and 'sell' a hop-up job to the admiring customer, he left ports slightly-rough, which promoted 'tumbling' of the gas flow, resulting in a more-thorough fuel-air mixture, delivered to the combustion chamber. Power went-up, the flathead Harley-Davidson KRTT beat the British Triumph Daytona 500cc roadracers in 1968 and 1969, after being beaten by them in 1966 and 1967. Triumph fans were crowing about the OHV Triumph twins being 'the end of the line' for the Harley-Davidson, until Jerry Branch working for the Harley-Davidson factory racing effort, and Cal Rayborn riding for them, demonstrated that sound engineering can benefit a design considered obsolete by many.
 
Aw c'mon lads give him a break? He has a shovel and wants to use it.

40mm carbs do work as I have 40mm Mikuni DTMR's on mine...but I also have 1300cc and gas flowed heads.

No-one is saying larger carbs won't produce the power, but what they are saying is that it is roundabouts and swings - you don't get owt for nowt and what you gain at one end you will loose elsewhere.

Rather that beat your head against a hard surface why not just say 'intercourse the lot of you', go away and fit the carbs of your choice then come back with torque and power plots that are better than a well set up OE Max.

I for one will be quite happy to admit I was wrong and kneel at the feet of a superior being.
 
I think we need to consider that people can have differences of opinion, even if they're wrong
Not in mathematics. You are either right or you are wrong. When you post some completely FOS math to try to BS your way to being believed it's exactly that: BS.

If all you said was "put a bigger carb on it" then fine. Go ahead. Nobody cares. It's been done to death and has never to this point worked out.

But don't make up some BS formula that any graduate of GT can look at and INSTANTLY tell it's BS and try to pass it off as fact, or even opinion for that matter. Because it isn't.
 
It reminds me how I tried to explain to Harley people that torque doesn't matter, torque cannot move bikes, power does. It was useless, because I was explaining something I learned in school at age of about 12, and they probably never went to school.
 
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Folks should take a deep breath and chill.

The best explanation is MM. It's about getting a flat torque curve.

Below is a chart from a tuned Ford crossflow engine (not sure of capacity but 1600-1770 cc).

The torque curve is 'n' shaped.

I think of the vmax as being two set of carbs each with theit own 'n' shaped torque curve but at different rpm. The vboost merges them together to be rather flat.

As MM says, there are other ways to do this.

Screenshot_20210718-221456.jpg

Notice the flat torque.
Screenshot_20210718-221253.jpg
 
It reminds me how I tried to explain to Harley people that torque doesn't matter, torque cannot move bikes, power does. It was useless, because I was explaining something I learned in school at age of about 12, and they probably never went to school.
HP = Torque X RPM.

You MUST have torque before you can have ANY HP. Unless you're going WFO and rarely have to drop RPM, brake or slow down, torque is far more important than overall HP, and without a lot of it, you'll never have a lot of HP. Torque is what accelerates the engine RPM and consequently your butt.
 
HP = Torque X RPM.

You MUST have torque before you can have ANY HP. Unless you're going WFO and rarely have to drop RPM, brake or slow down, torque is far more important than overall HP, and without a lot of it, you'll never have a lot of HP. Torque is what accelerates the engine RPM and consequently your butt.
Your torque number is useless unless you know RPM. Well, if you know 2 numbers, that is power. If you take 10 foot long board and stick it in rear wheel of your bike, you will create torque more than Hayabusa. Can you move bike with this torque? No, you cannot! Because you cannot create RPM with 2x4! Any 10 years old girl can create huge torque! This is probably 10th time, I am trying to explain it. Useless! My VTX1800 has more torque than Vmax. Which bike will go faster?

Here is another example for you. 2 Bandits are at traffic light. One is 600, another 1200. Which one starts faster? It is a simple question only for simple people. Real answer is: It depends at which RPM each biker releases clutch!!! Because 600 cc bike will move with more power if biker releases clutch at 6000RPM comparing to 1200 cc biker who relases clutch at 1500RPM. Power!!! Torque is nothing! If you still didn't get it, I am done!!! 😁
 
Here is another example for you. 2 Bandits are at traffic light. One is 600, another 1200. Which one starts faster? It is a simple question only for simple people. Real answer is: It depends at which RPM each biker releases clutch!!! Because 600 cc bike will move with more power if biker releases clutch at 6000RPM comparing to 1200 cc biker who relases clutch at 1500RPM. Power!!! Torque is nothing! If you still didn't get it, I am done!!! 😁
If you have slicks on both bikes and neither one spins traction. The bike with the 6000 rpm release but no torque will bog down and stall out. The bike with 1500 rpm but a mountain of torque will launch out of the hole like a beast. BUT, without HP to compliment the torque (usually gained from RPM) he would be overcome as soon as the smaller CC bike finally got moving.

And,
You don't need more then around 200cfm of flow for this engine. That is a basic function of RPM and various flow factors the engine is capable of and the estimated peak power. More CFM will help achieve the peak power but sacrifice the low end power. So good for racing where most of the time you're at higher RPM but on the street it will not work well for basic acceleration around town. You may have to downshift 2 or 3 gears to get it in the RPM range that it's all breathing well enough vs simply being able to accelerate without downshifting.

Many years ago there were a few "trick" carbs done by overboring a stock set about 2mm (I have a set around here). It took maybe 4 or 5 sets of carbs to get some that the castings were able to do that without causing an issue with throttle plates not laying in the correct position relative to the various circuits in the body. Small gains were found but at great cost (carb racks are not cheap much less maching something that turns one into junk).
 
Your torque number is useless unless you know RPM. Well, if you know 2 numbers, that is power. If you take 10 foot long board and stick it in rear wheel of your bike, you will create torque more than Hayabusa. Can you move bike with this torque? No, you cannot! Because you cannot create RPM with 2x4! Any 10 years old girl can create huge torque! This is probably 10th time, I am trying to explain it. Useless! My VTX1800 has more torque than Vmax. Which bike will go faster?

Here is another example for you. 2 Bandits are at traffic light. One is 600, another 1200. Which one starts faster? It is a simple question only for simple people. Real answer is: It depends at which RPM each biker releases clutch!!! Because 600 cc bike will move with more power if biker releases clutch at 6000RPM comparing to 1200 cc biker who relases clutch at 1500RPM. Power!!! Torque is nothing! If you still didn't get it, I am done!!! 😁
Can you spin that 10 ft board at 7500 RPM ? Not likely so zero RPM, zero HP.
Can the 10 yr old girl spin her huge torque at 1500 RPM ? Not likely so zero RPM, zero HP.

If the torque is nothing, HP = ZERO. Torque is the fundamental component of horsepower. Lots of RPM and little torque is like a weed whip. Lots of torque and little RPM is like a 25 HP tractor. Lots of RPM and lots of torque = lots of HP. Go study some dyno graphs, you'll see that high HP engines make a lot of torque.

Next subject, LOL ?
 
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Torque is nothing!
Wow. Just wow.

Torque, contrary to your misguided beliefs, is literally everything. You can't figure horsepower without it. In fact, here's the formula for calculating horsepower:

HP = Fd/t

Where HP is horsepower, F is Force In Pounds, d is Distance and t is time in minutes.
 
OK, this discussion is endless. Let us hear Fire medic, he knows everything! Maybe I am wrong.(just trying to end discussion) 😁
I had Chinese scooter 150cc, it had huge torque and power! Probably it had V-boost and carburetors from ZX11... 😁
 
Thanks! I am getting smarter every day! 😁

A sarcastic individual might suggest that if you are starting from a low base that wouldn't be difficult.
I, of course, wouldn't even entertain such a thought. ;)

It reminds me how I tried to explain to Harley people that torque doesn't matter, torque cannot move bikes, power does. It was useless, because I was explaining something I learned in school at age of about 12, and they probably never went to school.

I imagine that was received with interest and universal acceptance?

You still don't seem to have grasped the basics of what an engine does i.e. it turns a reciprocation movement into a rotating force or to put it another way it is doing work.

The amount of work the engine is doing is expressed in Newton meters (Nm). As mentioned previously as power is a function of torque x r.p.m. therefore you can't produce the former without the latter.
IMO to say the either power or torque is more important than the other depends on what it is you are trying to achieve. It is this which will determine on how you configure the torque and power delivery.

In your first post you wrote 'We just need to find a car with at least 145 HP (same air and fuel amount), no big deal!'.
This would need to be naturally aspirated, carburated and have a similar displacement to the Max.
Assuming you are staying in the realms of production vehicles (?), perhaps you could give us some insight as to which ones you have identified as suitable doners.
 

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