aidandj

iTrader: (5)

You should theoretically just be able to hit it at like 7500rpm. You will probably need EBC to keep it from spiking down low

patsmx5

iTrader: (16)

Hmm. Looks like I need to setup my boost to come up to around 350wtq and hold it there like you say, that's 500 wheel at 7500. Gonna need more fuel though, but still it's look promising.

deezums

iTrader: (3)

Why do you think you need bigger injectors? You aren't on e85, right, and you run the equivalent of 1200cc with your boosted fuel pressure?

That's like 700whp worth of fuel. With e85 it's still probably enough for 500-600 crank...

What's duty cycle doing during these pulls?

aidandj

iTrader: (5)

He is on e85

Also, unless you crank base pressure your differential fuel pressure is the same. which is what determines flow rate.

deezums

iTrader: (3)

Even still it's way more than enough.

Ditch the stupid atmo referenced NB **** and get a real 1:1 regulator on there and fix the pressure at 62psi if duty cycle is getting close. If your fuel pump keeps up you will not need larger injectors. All you gotta do is repourpose the evap lines, right?

patsmx5

iTrader: (16)

Yes on E85, I was at 90% duty cycle at 8,400 on the 376whp 3rd gear pull.

aidandj

iTrader: (5)

He has all that. But even at high boost, the flow rate is the same as at base pressure with a 1:1.

deezums

iTrader: (3)

That's NB right? The one that references 60 psi all the time. It's not a 1:1, it runs 60 psi all the time.

I still say switch to return style and up the pressure a tad.

aidandj

iTrader: (5)

He has 6an lines from the tank to rail.

Also, calculators are all ballpark. Engines all consume fuel slightly differently, and you won't know exactly when you will run out of fuel, until you go lean at max boost lol.

patsmx5

iTrader: (16)

I have all the fuel system. Walbro 450 and Walbro 255HP, 10 gauge wires/relays to each, 6AN lines, Aftermarket regulator with 1:1 reference and ID 1000s, and a fuel PSI sensor logging fuel pressure.

EDIT: Pic from log showing duty cycle/fuel PSI

deezums

iTrader: (3)

Well hell, crank the **** out of the pressure then. ID says the 1000's love 5 bar anyway, and you're set to do it.

aidandj

iTrader: (5)

I agree. 1000's have a max differential pressure of 101psi

So run a 100psi base pressure and go to town.

patsmx5

iTrader: (16)

Also why won't Tunerstudio let me raise my rev limit higher than 8,500? I want to bump it up a big, kept hitting the limiter earlier making pulls.

EDIT: Fixed, under "gauge and setting limits" you can adjust it there, then change rev limit higher.

glade

iTrader: (2)

It's so quiet!

18psi

iTrader: (76)

Yeah I'd agree with these young whippersnappers: crank the fuel pressure to ALLOFIT before you change those injectors.
If nothing else we'll all finally have some data on where they max out at full tilt.

The 400 number was assuming 60psi pressure, you have the pumps for way more than that.

pdexta

iTrader: (17)

I assume MAP is pressure at the manifold and Secondary MAP is between the turbos? It's interesting to see how the little turbo kicks in, then as the big turbo comes alive the little one seems to go away.

18psi

iTrader: (76)

so 140kpa from the 2nd turbo at 7200 rpm?

hector

Its amazing how much power it takes to compress air with the crankshaft as opposed to the exhaust

patsmx5

iTrader: (16)

Correct, MAP is total, Secondary MAP is the big turbo. The little turbo doesn't go away though, it keeps doing it's thing, it just sucks in boosted air at the higher revs for extra power.


Yes on that pull. It's at ~165kPa / ~ 10 PSI in that log.

Yes, I knew the SC was robbing lots of power after about 20 PSI.

In other news, found a small exhaust leak I fixed (pre-small turbo, will post pics later) and another probably bigger leak pre-big turbo I haven't fixed yet. The V-band on the rear is leaking where the big turbo is. I think I need a V-band gasket on that one... I nicked up the face of it and it's leaking. My fault, but gotta fix that.

Also about to install a restrictor on the big turbo. Small one has a built in restricer, big one did not and it's pushing oil out the turbine a bit. I tested the drain from it with the pump using clear tubing to "See" what's happening and the drain works great, but it's flowing 5x the amount of oil the front turbo drain flows. So it needs a restrictor me thinks.

Few small problems which is to be expected for a cheap DIY setup. No big problems yet.

Leafy

iTrader: (1)

With most fuel pump I dont think you can reasonable run a base pressure higher than 60psi and expect to crank 30psi of boost into it.