posted March 24, 2002 12:36 PM
Now a new question from all this,figure in a 30 to 50hp dry shot of nitrous on top of 195-200hp,where is the extra fuel going to come from if the injectors,with the muzzy pump are only good enough for just over 200hp?How has King ZX12 been running his dual stage dry kit with 250+hp and stock injectors and fuel pump without melting something?
posted March 24, 2002 05:16 PM
Interesting question on the stock fuel pump. Since our bikes don't have bowls to store fuel, I'd think fuel supply problems would surface quickly, especially those with nitrous. The Muzzy pump should support much more power than 200hp. I'd bet it's the same one they use for their turbo kit. If, mathematically, the Muzzy pump is only good for 200hp, what'a person to do? Bigger injectors? I'm guessing 80% is the max safe duty cycle for our injectors? What happens when they are maxed out? Will it shorten the lifespan of the injector? My engine makes a tad over 200hp with the stock fuel pump. The numbers in my map at 100% throttle are almost all less than +10. Don't these numbers represent the cycle time of the injector?
posted March 25, 2002 07:01 AM
Edited By: psycho1122 on 25 Mar 2002 07:09
Muzzy Pump I did not say the "Muzzy Pump" was ONLY good for 200 h.p.
The Muzzy Pump is a 350 lb/hr pump vs. the stocker at 200 lb/hr.
The Muzzy pump will flow more fuel, and as a result the psi in the system will have a slight rise. Let's say it will rise @ 2 psi as a result of the extra flow rate.....
The same injectors running 30.476 lb/hr, Equates to @195 h.p. (I stand corrected), w/ the extra pressure the lb/hr rises to 31.17 w/ = 199.51 h.p.
Now, what if the pressure rises higher than 2 psi to let's say 50 psi?! now the rating on the same injectors goes to 32.67 lb/hr w/ = 209.11 h.p.
Now I'm shure these are "Optimum" figures, you can do the math yourself at the RC website. If you do get higher h.p. #'s then you may be past the 80% duty cycle. Doug did say that you are on the "EDGE" w/ the stock pump and here you can see why.
On a final note.....Fuel supply/Engine combustion temp's are different between the 1/4 mile and 2-5 miles at Bonniville!
____________
You say PSYCHO like it's a BAD thing!!
posted March 25, 2002 07:32 AM
Edited By: Y2KZX12R on 25 Mar 2002 07:36
Great info guys, somthing to remember thou...
If you guys arnt changing the pressure regulator then the pressure shouldnt rise at all.
The regulator will just send the extra volume back to the tank.
Combustion temps shouldnt change without a fuel change. The combustion temps change with A/F ratio changes and also type of gasoline.
posted March 25, 2002 07:58 AM
Regulator Y2K....The regulators job is to "Drop" pressure at idle to keep engine from flooding. It drops to @41 psi at idle.
____________
You say PSYCHO like it's a BAD thing!!
posted March 25, 2002 09:27 AM
I isn't there ONLY drop pressure at "high vacumm".
BEAR (and others) has raised his overall fuel pressure for HIS 200+hp by squeezing the regulator in a vise!!!
posted March 25, 2002 11:26 PM
Edited By: kcadby on 25 Mar 2002 23:27
I don't know how/why he hasn't hurt anything without changing the injectors or pump...but he hasn't...
I rode BOTH of his bikes and they DEFINITELY had more than a 40-shot!!!
He used a resistor in-line with the water temp sensor and the temp sensor in the air box does the rest...
posted March 26, 2002 03:28 PM
You guys (not all) don't understand how the regulator on the 12 works. It is normally closed. Full head pressure from the pump is always acting on the injectors. It opens at high vacuum (idle) to "dump" a little fuel pressure, 3-5 lbs or so, to lean out the idle. The '02 does not have this "feature". The fuel rail is left unmachined and the fuel pressure is limited by an integral pressure regulator (bypass) at the pump in the tank.
Doug
____________
It's not that I think you're dumb, it's just that so much of what you know isn't true....
posted March 26, 2002 10:37 PM
Hmmm...I guess BEAR is wrong with what he said/did then???
He said he raised his fuel pressure by "tweeking" the regulator...
My fault...again...for NOT reading the book first
Thank's Doug...
posted March 27, 2002 02:56 AM
Edited By: Y2KZX12R on 29 Mar 2002 13:23
Ken, It is possable to tamper with the regulator. Its just a spring pushing on a seat. The best way is to remove the "hat" and make a new one that has a screw on the end where the vacuum connection is and move the vacuum connection to the side of the hat. The new hat is clamped on. I wouldnt know how to modify a 2002, I havent seen one.
I didnt even know they had changed the setup for 2002.
posted March 27, 2002 07:33 AM
Y2,
HElloo!! You CAN "Tamper" with the regulator, you just can't raise the fuel pressure anywhere but at idle. The regulator is ALWAYS CLOSED.
Doug
____________
It's not that I think you're dumb, it's just that so much of what you know isn't true....
posted March 27, 2002 08:26 AM
Edited By: Y2KZX12R on 28 Mar 2002 04:32
So Doug, you are saying that if the vacuum line is disconnected then there is zero flow in the return line back to the fuel tank? And that only at an idle with the vacuum line connected, is there any return line flow back to the tank?
If this is the case then it would be the first time on any fuel injection system that I've ever seen that didnt use a regulator to control the fuel rail pressure at all times.
Also if this is the case then as fuel pump performance decreased with the age of the pump, then so would the rail pressure because rail pressure would be determined by pump output not the regulator.
posted March 27, 2002 11:05 AM
Exactly Y2K This is why the Muzzy "High Flow" pump will be so important for a built engine.....Even if the flow decreases over time, it still will supply more than enough fuel for 200+ H.P. applications.
____________
You say PSYCHO like it's a BAD thing!!
posted March 27, 2002 08:32 PM
OK everybody,
Are you sitting down? I don't know how to say this but....
I....I.....I....WWwwwas WRONG!@ THere I said it. Fuck.
Anyway, Y2k is perfectly right. I know this because I just came in from the garage where I hooked up an air source and regulator to a set of throttle bodies. And as you can expect, and as Y2 correctly states, the regulator does bleed pressure off over about 55psi. (It ALSO bleeds pressure when given an idle vacuum signal like I said earlier).I could swear (and kind of did I guess) that when I did this last summer I did not get these results. Prior to that, I was told by a pretty reliable source at KMC that the regulator only served to drop pressure at idle. That's why I tested it then. Anyway tonight my results were different.Shit. Mea Culpa
Doug
____________
It's not that I think you're dumb, it's just that so much of what you know isn't true....
posted March 28, 2002 04:46 AM
Thanks for clearing that up Doug.
No biggie, it just didnt sound right.
So, 55 psi is your rail pressure with the vacuum line off?
It seems they vary from the factory. From the factory mine was 51 psi and droped under load to 50 psi.
Last spring after an "adjustment" I set it to 53/52.
It really shouldnt drop at all under load but it seems to for whatever reason.
posted March 28, 2002 07:26 PM
Fuel Pressure Regulator
quote:OK everybody,
Are you sitting down? I don't know how to say this but....
I....I.....I....WWwwwas WRONG!@ THere I said it. Fuck.
Anyway, Y2k is perfectly right. I know this because I just came in from the garage where I hooked up an air source and regulator to a set of throttle bodies. And as you can expect, and as Y2 correctly states, the regulator does bleed pressure off over about 55psi. (It ALSO bleeds pressure when given an idle vacuum signal like I said earlier).I could swear (and kind of did I guess) that when I did this last summer I did not get these results. Prior to that, I was told by a pretty reliable source at KMC that the regulator only served to drop pressure at idle. That's why I tested it then. Anyway tonight my results were different.Shit. Mea Culpa
Doug
OK... This is great... now why are we not getting adjustable fuel pressure regulators from Muzzys/Other Shops to slightly raise the fuel pressure to our injectors, to make sure the fuel pressure is optimum? Mike from HPU... are you there? I have an adjustable regulator on my turbo for this exact reason.
posted March 29, 2002 07:48 AM
You haven't gotten an adjustable regulator from us becasue you got a fuel pump with much greater FLOW at the same pressure. That pressure, 50 psi give or take, is plenty. you just have to maintain it and the bigger pump will do that.
Doug
____________
It's not that I think you're dumb, it's just that so much of what you know isn't true....
posted March 29, 2002 01:23 PM
An adjustable regulator could be a valuable tuning tool.
On the chassis dyno I've seen the fuel rail pressure to be very usefull in dialing in engines. Believe it or not one particular engine (1994 Z28 procharger/intercooler) liked a 4 psi drop in rail pressure. It went from 392 hp to 416 hp with that particular change. Some times you never know what will work on the dyno.
There is a hat that will fit the zx12r regulator. I had an after market one for an 87 grand national that fit nicely. The spring was broken in it but all I needed was the hat.
I dont know who made this particular one I took it off the car many,many years ago. Its either a spun aluminum hat or its made from billet.
I didnt see any difference with 5 psi changes other than a general A/F ratio change across the board.
It really needs to be mapped on a DJ250 with each pressure change. Somthing I was unable to do last year.
posted March 30, 2002 04:39 PM
Edited By: psycho1122 on 30 Mar 2002 16:43
DECK HIGHT Checked deck hight this morning w/ new cylinder and pistons.....Found that w/o base gasket, I will be able to get within .5mm of Zero Deck. Interesting to see that Kawi built a little bit of "cushin" in the compression ratio dept.
Will be using 1104 between upper case and cylinders.
Final assembly will happen next Wed....
____________
You say PSYCHO like it's a BAD thing!!
All times are America/Va [ This thread is 4 pages long: 1234Next» ]
HOME
NEW TOPIC
posted March 24, 2002 12:36 PM
posted March 24, 2002 05:16 PM
posted March 25, 2002 07:01 AM
Edited By: 
posted March 25, 2002 07:58 AM
posted March 27, 2002 11:05 AM
