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Ifrit
07-26-2015, 03:55 PM
Ok so i got a list of stuff im looking for info on,

First, at WOT up until ~3500 RPM i'm making 10psi on the stock gauge (same on 2 different clusters), then as i move past 3500 nearing redline im gaining boost to about 13-14psi.
but at this time im only about ~45lbs of fuel. At vacuum im at 36-38lbs. At WOT im running at about 11.9AFR. Trying to figure out where my extra 8lbs of fuel is going.

Second, Im currently getting chatter from my engine and at first thought it to be my blower, but i checked it and sure its a little noisier then a stock one but not much. So my next question is do my roller rockers need to be adjusted again? im running scorpions 1.73 on a 273HR112 comp cam and if so where can i find the instructions for adjusting lash.

Any info would be awesome thanks.

racecougar
07-26-2015, 09:52 PM
The FPR raises and lowers the fuel pressure at the rail to maintain the same differential over manifold pressure. You should actually see a wider range than you've reported, with fuel pressure set to ~39-40 psi at 0 inHg/PSI manifold pressure.

820
07-26-2015, 10:35 PM
I would say your 8lbs is going out the tail pipe.

Ifrit
07-27-2015, 10:51 AM
The FPR raises and lowers the fuel pressure at the rail to maintain the same differential over manifold pressure. You should actually see a wider range than you've reported, with fuel pressure set to ~39-40 psi at 0 inHg/PSI manifold pressure.

I know that at 0 inHg i should be at 40lbs and then after for every 1 psi of boost i should make 1 in fuel but im not. At 13psi i should have 53lbs of fuel but i am not making it.

Ifrit
07-28-2015, 12:11 AM
Also wanted to know what could cause my cluster to read a higher rmp then what my car is running at? On BE im at about 850 and on the cluster im at 1000 - 1100

HwyStar
07-28-2015, 08:17 AM
I've noticed that too on my car. It seems to be close at idle, but above that there is a divide between the aftermarket tach and factory tach.

FrankenBird
07-28-2015, 09:17 AM
my old tach was off also.. it would say I was at 3500 rpms with overdrive on at 55mph..i knew it was wrong because I could hear the rev of the engine. I replaced the tach and it all good...I have an extra one if ud need one.

David Neibert
07-28-2015, 11:56 AM
Also wanted to know what could cause my cluster to read a higher rmp then what my car is running at? On BE im at about 850 and on the cluster im at 1000 - 1100

Stock tachometer isn't very accurate, especially in the upper rpms.

David

David Neibert
07-28-2015, 12:01 PM
I know that at 0 inHg i should be at 40lbs and then after for every 1 psi of boost i should make 1 in fuel but im not. At 13psi i should have 53lbs of fuel but i am not making it.

There are several possibilities.

Vacuum/boost refrence hose to regulator is cracked or leaking.

Fuel filter is dirty and restricting flow

Fuel pump is weak and needs replacement or increase in size.

Voltage to fuel pump is falling off at higher rpms which could be caused by a weak alternator, slipping accessory belt or excessive voltage/amp draw for electrical items you have added.

David

Ifrit
07-30-2015, 04:51 PM
There are several possibilities.

Vacuum/boost refrence hose to regulator is cracked or leaking.

Fuel filter is dirty and restricting flow

Fuel pump is weak and needs replacement or increase in size.

Voltage to fuel pump is falling off at higher rpms which could be caused by a weak alternator, slipping accessory belt or excessive voltage/amp draw for electrical items you have added.

David

I can check the vacuum hose, fuel filter is a possibility and i can change that no problem, fuel pump is new ish and im charging at 14.7-15V. I do have a battery light on for high amps. If i remember properly this new alternator is putting out 220amps.

Ifrit
08-06-2015, 06:42 PM
What about the scorpion roller rockers? do they need to be adjusted after a give period of time? and if so do i just redo them like when they were brand new?

820
08-06-2015, 08:16 PM
Do you hear any valve train noise?

Ifrit
08-06-2015, 10:10 PM
Do you hear any valve train noise?

There is some kind of chatter, first guess was blower but it was not that. next guess was my rockers.

KMT
08-06-2015, 10:13 PM
There is a chance the clatter comes from using an oil filter with a lax or missing drain back valve...

racecougar
08-06-2015, 10:33 PM
What about the scorpion roller rockers? do they need to be adjusted after a give period of time? and if so do i just redo them like when they were brand new?

Are your rockers not pedestal mount? If so, lifter preload is determined by pushrod length.



There is a chance the clatter comes from using an oil filter with a lax or missing drain back valve...

Only if the rattle occurs solely at startup.

KMT
08-07-2015, 12:37 AM
Only if the rattle occurs solely at startup.

That's where the 'chance' comes in, but thanks for confirming.

Ifrit
08-07-2015, 03:36 AM
I would figure that the rockers are a pedistal mount, and the chatter is all the time. I know its a hard thing to figure out with out hearing the car in person.

KMT
08-07-2015, 10:26 AM
I would figure that the rockers are a pedistal mount, and the chatter is all the time. I know its a hard thing to figure out with out hearing the car in person.

Yes, that's not an weak oil filter issue, then. Maybe you can capture a short video and post it? It would be interesting to try to determine if it is just one or two, or all.

Ifrit
08-07-2015, 10:39 PM
Yes, that's not an weak oil filter issue, then. Maybe you can capture a short video and post it? It would be interesting to try to determine if it is just one or two, or all.

Yes when i get a chance ill upload a video, Just got to get around to dragging my laptop out to my car in order to start it..... Yea that is another thing, my QH keeps putting my ecu into protect mode, (fans come on full blast with Key on Engine off and car will not run) until i re-upload my tune to the chip. But yea I will try and get a Video.