knock and popping

[booth1]

im new to f/i and have the poo scaired out of me yesterday and am hoping you guys can help. i have been noticing popping coming from the exhaust when i roll into the throttle while going down the road and sometimes i even get knock showing on the gauge so i havnt been driving the car hard untill yesterday i was merging onto the highway so i punched it and heard popping and the knock gauge shot into the red so i got out of it.. since i wasnt at full throttle the scanmaster didnt save the o2 or retard..

any help as to what could cause this would be appreciated

 

[booth1]

mods are
3200 stall
.20 over
204/214 cam
te63
60# inj.
snow alky

 

[Gnology]

How much boost? Fuel pressure setting? Sounds lean.

 

[booth1]

it runs 23 lbs of boost and fuel press is 39 at idle and nearly 60 wot. the o2 on my last little romp was 768 and retard was 1.4 after my knock gauge slowly climbed into the first orange light.. so it is intermittant sometimes it woint knock at all and one time it jumped into the red.. any thoughts?

 

[jasjamz]

Fuel pressure should hit 66-68psi at WOT. It's too lean. remove the vacuum line from the regulator and block it off. The pressure should read 43psi or whatever you chip maker suggested. Now when you attach the vacuum line it should fall like 5psi to 38. If you have any leaks in the system it will not allow the regulator to function correctly. Post your scanmaster readings at idle. Also, does the car have a fuel pump hotwire kit?

 

[Gnology]

Just a quick question, is the fp 39 static or under vacuum? Vacuum line off or on the regulator at idle?

 

[booth1]

the fp does like you say it should it jumps up to 42 43 when i pull the vac off. as fas as 68 at wot it may be as its somewhat hard to read the gague press up against the windsheild just above the wiper when im flooring it..
but my scan master readings are as follows

after a little spin around base
o2 785-820 retard 0.0
af 05
l8 35
bat 13.6
int 128
bl 126
mph 00
clt 164
ats 123
r 800
tps .42
iac 13
cc 13
mal 00

 

[BlackBandit]

Do you ever hear the popping when you're not on the throttle hard?

 

[booth1]

no

 

[BlackBandit]

What chip are you running and are you running alky? If you're running alky is it possible you forgot to prime it?

 

[booth1]

yes im running alky and a big fuel pump with hotwire. it is set up as it was when i bought it. the chip is a turbo tweek also in it since i bought it

 

[jasjamz]

Inform us on your spark plugs, plug gap, age, and wires.
Scanmaster numbers look goog. I would back the boost down and see if it happens at like 17/18psi.

 

[booth1]

im not sure about all of that ive only had the car since sept of last year but the motor has only been in the car for about 16k. i have been driving it for about 4k and whatever is going on is new

 

[Gnology]

Back to fuel... You say that when you pull the vacuum line off, the pressure only goes from 39 to 42? And you think that it may be 60 instead of 68 at 23#s of boost?

If so, seems like the vacuum line feeding the fuel pressure regulator may have a leak or maybe a bad reg? 39 to 42 is not much change should be more like 34 to 42, and you've already stated the WOT difference.

I agree to drop boost down to about 15 and really watch WOT Fuel pressure. 2 reasons, if you are lean popping, your safer at 15, and if your running 15 instead of 23#s you dont have to try so hard to stay in the road.

 

[booth1]

alright ill turn down the boost and try to see my fp when i get back (gotta leave town for a couple weeks) thank you for the help i should be back 1 june