NFL that looks crazy man. When r we going to see that thing run?
Bring that bad boy to pismo on thanksgiving.

WHY can't you say how much power it makes? no dyno yet or what ?

WHY can't you say how much power it makes? no dyno yet or what ?

Thanks! This set up flows! Had to slow it down a bit on the exhaust sidewith a little more of a restrictive exhaust! CUSTOM HEAD PIPE WAS MADE .Without the flow bench it would not have been possible !

Anyone wanna guess the power it puts out on a 600cc TRX ? Cant say but we will have it out for the race in DUMONT in December ! I hope that they dont make us put it in another class! Its still just a lil ol 450r By the way we need a light chasie to put this thing in anyone wanna be the first to try it?

Some people live and die by dyno numbers....

man that bottom exhaust port is crooked as hell. it looks like the lip isnt the same measurement all the way around,

Anyone wanna guess the power it puts out on a 600cc TRX ? Cant say but we will have it out for the race in DUMONT in December ! I hope that they dont make us put it in another class! Its still just a lil ol 450r By the way we need a light chasie to put this thing in anyone wanna be the first to try it?

Dec 8 you can run us all you want. They own their 450, the raptors are mine, but I would be happy to beat you on them. They launch harder with a heavier rider on anyway. Hopefully you have made up that 5 bike lengths that our 550 laid down against your 600.

By the way the 3 of them weigh between 120 - 130 lbs.

If you are informing the community of your build fine. If you are trying to market and sell them in this thread I will remove it. This is not the place!

[quote=Quadracers]
that have light chasies ,and a jockey the same weight as your sons and my 600 cc trx I can assure you would beat all the 650 and smaller all gas class! My 12mill trx kickinsand in my competitors faces priceless for all my competitors theres visa,mastercard better get it out your going to need it!

that way then you dont get the Bs and your thread wont get deleted.


Yep

By the way everyone one BIG carb flows better than two small ones. Don't be fooled! The 660 raptors have been doing this for years.

Um no we don't. I like the idea he stepped out to try something different. BTW show me ANY shop/person that builds single carb raptors that has won any type of drag or hill event. The new 700's have a combined intake but thats another story. I know of one guy building a 3 runner setup for a 5valve raptor head. The single setups are for the lazy people who cant tune.
The fast DS's are using twins also.
I am not sold on the exhaust porting yet but I like the intakes on that head.

cant we all just get alone?????? both of you guys have great running bikes. Quadracers you own me 400 dollars. i had to buy nos so your boys wouldnt beat me anymore(ha ha)my stock bore beats most of the big bores at pismo except your boys 2 yfzs

We will be at AVI.


That was our YFZ and Woodpeckers honda that you desribed. Our YFZ's did not race NFL during the Pismo event.

My comment on duals verse single was directed towards the build and class we are talking about 450's, even though I referred to the raptors doing it. Craycraft has done testing and has won races using a single, but my personal 660 based raptor has duels and I agree that with a big bore/stroker raptor it is a must.

Duel carbs are a much better race setup. With a drag pipe they will make it possible to cam a bike to run peak hp from the starting line all the way to the traps.

A single carb will make more peak torque but it will build up fast and drop off just as fast.

Yamaha shot themselves in the foot on the racing application with the 700R when they didn't give it dual intake ports. I know why they did it but it will be a limiting factor unless someone does the same thing to it.

Good Job NFL! You are def on the right track!

i jus wont to know how much a head and cam setup like this would cost... im kinda intrested in something like this..
by the way... what size carbs and valves go with this head?

DSNUT what different carb size combinations(single -vs- duel) have you tried to see these results? You could save me some heartache with a little info...LOL.

i jus wont to know how much a head and cam setup like this would cost... im kinda intrested in something like this..
by the way... what size carbs and valves go with this head?

What everyone has forgot is that NFL is Leadfoot. The owner/ builder of the infamous TRX turbo was a total slug and he also said his nitro Predator that would smoke everyone too. I think he changed his screen name over the turbo embarassment.

I was doing some thinking about the twin carb setup compared to the big single and why it works best. This is what i came up with. I am not an expert in physics so this explanation might have a few holes in it but here it is.....

It isn't just about volume (CFM). The single 50 might have more CFM than dual 38's. I haven't done the math on that.

What it is about is ramp rate and volumetric efficiency. Which setup do you think will be better suited to fill the cylinder more completely at low rpm?

Now which setup will be better suited to fill the cylinder more completely at high rpm?

The intake air is constantly starting and stopping as the vacuum signature of the piston dropping on the intake stroke gets blocked by the closed intake valves during combustion and the exhaust stroke.

Which carb setup will more easily pick up velocity and volume when the intake valves open again?

Here is the big one: Which carb setup has higher velocity? Intuitively the first response is to assume the smaller carbs will have more velocity but that is not true from a physics standpoint. In reality, velocity is volume over time. The smaller carbs are running about half the volume over a given time frame each as compared to the bigger carb so the smaller carbs each actually have much less velocity.

That means that the twin smaller carbs can move about the same CFM into the chamber but they can do it at a lower velocity with a much quicker pick-up from the vacuum signature. Knowing this begs the question which setup will have less turbulance and reversion in the intake ports? The setup with the least velocity will. Think about throwing a rubber ball at a concrete wall. The faster you throw it, the quicker and farther it bounces back. This is what happens to the air when the intake valves close.

This added efficiency and almost equal CFM allows you to maintain a higher VE at higher rpms.

The twin carbs will mean slower air measured at the carbs but they will provide faster and more focused air entering the cylinder.


Sorry for the book! Just some things to think about.

dood,.. no offense,....I'm not trying to be a deekhead, but you should delete your entire post... your physics is wacked!

the only thing of value was when you mentioned volumetric efficiency... concentrating on VE is what builds power,....from the dyno curves John has posted he should concentrate more on VE than the two carb setup imo...being 100% efficient is making more than he posted.. use his dyno post as an example and crunching a couple volumetric efficiency equations at various rpms, you'd be real shocked.

the greatest restriction in the entire head is the valve,... its not the port, and a single 43mm fcr carb will flow near 375cfm at 28"wc,.. more than enough flow...

velocity is dependent upon cross-sectional area.... the two smaller carb setup has 13% more cross sectional area than the one large carb setup. velocity is inversely proportional to cross-sectional area,... meaning the bigger the carb the lower the velocity through its venturi...

getting higher volumetric efficiencies, thus higher hp,is not dependent upon a two carb setup.... controlling reversion, ram filling, maximizing front to back flow ratios is of greater concern...

John,... again, I apologize to you if you think I'm against your efforts, cause I'm not,... I actually commend your R&D,... I understand that in order to be successful you must have failure,... my entire point is that I think you may need to 'reverse' engineer your numbers to find greater gains...

Good luck.

dood,.. no offense,....I'm not trying to be a deekhead, but you should delete your entire post... your physics is wacked!

I disagree.

velocity is dependent upon cross-sectional area.... the two smaller carb setup has 13% more cross sectional area than the one large carb setup. velocity is inversely proportional to cross-sectional area,... meaning the bigger the carb the lower the velocity through its venturi...

So this build is making 100% VE at 9500 rpm? Why?

What does the bike run in 300' just out of curiosity? How much does it weigh?

Here is a few pics of my high flow head used on a couple of big cc TRXS I build!I wonder how it would work on a stock bore build? This is at the beginning stages ! A few people asked me to share!

soo how do you get a motor to "suck" harder than it should or "open its big mouth" a lil bigger... hmmmm

and i am curious how do you figure ve with a dyno run and hp/ tq numbers. i have seen caculators at different sites for that but just curious to see..

Um no we don't. I like the idea he stepped out to try something different. BTW show me ANY shop/person that builds single carb raptors that has won any type of drag or hill event. The new 700's have a combined intake but thats another story. I know of one guy building a 3 runner setup for a 5valve raptor head. The single setups are for the lazy people who cant tune.
The fast DS's are using twins also.
I am not sold on the exhaust porting yet but I like the intakes on that head.