enzo250

Thanks Crispeed and HWO.. It seems that we are the only ones who can see that there is some serious supply problems somewhere... And they need to address the problem..

enzo250

The Big Blue as i call it.. (paxton) is a good pump but loses alot of flow at higher psi's.. It will support upto 600HP. If your planning to make more HP add another Paxton or look into the new Aeromotive Pro pump or Weldon Pumps..

crispeed

Hey Barry!
I might not be correct but I believe Peter(Riceracing) is running his injectors in sequential so with 4X880cc it's like running with slightly larger than 1600's in the secondaries with a Haltech in staged mode!

crispeed

crispeed

Next question for everyone running with 4X1600's!
How much horsepower are you actually making and at how much boost?

crispeed

Greg

That is BHP not WHP.

enzo250

You don't need that much pressure when you have VOLUME...
YOU NEED VOLUME NOT PRESSURE...

setzep

Still confused why you think you need -10 lines??

Jedon

This whole volume vs. pressure issue is great!
I am aiming for 450RWHP
Should I do 2x850 + 2x1500 at stock pressure (Walbro pump)
or
2x550 + 2x1500 with a FPR at 70psi?
I don't want to use a custom rail or bosch injectors and need to keep costs down.
Thanx!
-Jedon

waynespeed

One of the most popular dyno's in NYC were churning out over 600+RWHP on a street ported REW with the big pump -10 lines and 4x1600cc injectors.

They didn't always have this setup. They started out with 850/1600cc combo. If these guys have a dyno to use at will and are a major dealer for Haltech and other high performance products and ended up using the 4x1600cc setup on many of their custumer's cars maybe they have seen something where the 850/1600cc injectors weren't cutting it.

To conclude, sure smaller injectors may have better spray patterns than the 1600cc injectors. These may not be well suited on a daily driven where extremely light load situations will reduce drivability. However, they do work well for 600+hp and are capable of more especially on high reving high boost motors.

Just my 2 cents.

peejay

I'm watching with interest... really. But I had a thought...

I wonder if anyone in the thread has worked the math? 6400cc per minute (which is what 4x1600's is total) divided by .095238 (conversion factor) equals about 610 pounds per hour. Assuming a .60 BSFC, that comes out to the ability to support 1016hp at wide-open, or 863hp at 85% duty cycle.

My BSFC is probably off but should be fairly close... but why should you need 4x1600's to support hundreds less HP? Unless you're running excessively rich, or your ignition is tuned very very conservatively so you need to dump more air and fuel in for the same HP, or both? (At that point you'd probably be fouling plugs constantly, breaking seals from carbon clogging, and burning up turbines left and right)

Again, I'm just lurking and amassing info, and I'm just wondering why nobody decided to show the math yet. Or am I just way off base here?

waynespeed

Exactly what i'm saying, you are right on target. When using 4x1600cc you won't have to worry about not enough fuel. Furthermore, if you plan to put down 700rwhp this setup will cover all bases with room for more. I'm not looking for merely 500HP. Case closed.

peejay

Sure you have to worry about having enough fuel.... for starters, you need a fuel pump that can supply 610lb of fuel per hour. All the injectors in the world aren't good enough if your pump can't flow enough, right? 610lb/hr is about 385lph, at whatever your max fuel pressure is, plus you'll want safety margin...

Looking at it objectively (instead of looking only at the dyno charts and timeslips in my mind ) it only makes logical sense that, before anything is done, the fuel pump must be upgraded, and the lines (if I want more than 450hp), and the injectors, which of course requires tuning...

Maybe we should stop glamorizing big turbos, we should start ogling fuel pumps that could drain a tank in a minute (which isn't really an exaggeration either...)

enzo250

Well said peejay...

enzo250

Well Waynespeed, I live in NY and i think i know who your talking about here. Let me just say that a dynojet is not an ideal dyno to tune with. Plus owning a dyno doesn't necessary mean you know what your doing(tuning wise). The best tuner in NY tunes on the street.

waynespeed

Hey enzo250, I respect everyone's views and opinions and believe me I don't expect likewise from a public forum. I just wanted to share my findings with my rotary brothers.


You've really got me thinking. Who are you talking about("The best tuner in NY tunes on the street." ?

enzo250

No hard feelings Waynespeed... it just gets me fired up when people suggest that you need such big injectors when the rest of their fuel system is not up to par.

Pm me if you want to know who the tuner is.

Maxthe7man

I thought I would add my .02 to this, first of all, fuel line sizing is as much as a science as turbo sizing, to small, no matter what pump you have, you starve of fuel, as the flow rate increase, the pressure drop becomes greater as well, and the pump has to work harder to supply a given pressure, and volume at then end of the fuel line, to big a fuel line, and during accelaration, the fuel pushes back on the pump, its a bell curve when it comes to getting the correct size, thats why running a surge tank is a neat idea, you supply the surge and maintain a level their, but then use a high pressure pump from the surge to the injectors, I would bet that if one were to run a surge tank, and supply with a mallory or holley low pressure/hi volume pump, and then had another pump pull from the surge and supply the injectos with 6 feet less of small fuel line, a smaller pump would support much more horsepower, OEM's don't oversize fuel lines, they put in as small as possible to save costs, the stock fuel lines are pretty tiny, and from my boinger experience, their is no way the stock fule lines are good for 500+ hp, I wonder how many people change their injectors and fueling chasing a lean condition that is a result of a choked up pump fighting a small fuel line, If you are running 500hp on the stock fuel line, you are not doing your fuel pump any favours, its like trying to blow a tennis ball through a garden hose...Max