Fuel pressure to low?

[djj624]

Just checked fp. Got 34 line on 38 line off and 55/56 at WOT with 16.5lbs of boost. Seems low correct in thinking 38 line on 42 line off and roughly 60 at WOT?

Galaxy S7 Edge

 

[Grand_87_national]

Just checked fp. Got 34 line on 38 line off and 55/56 at WOT with 16.5lbs of boost. Seems low correct in thinking 38 line on 42 line off and roughly 60 at WOT?

Galaxy S7 Edge

43 psi line off is a good baseline. Are you lean at w.o.t.? Do you have a wideband o2, or a scanmaster ?

 

[djj624]

I'm in the 800's at WOT on the scanmaster but I'm seeing knock .

Galaxy S7 Edge

 

[Grand_87_national]

Have you tried it at 43 psi line off? Someone with more experience on 91-93 octane fuel will likely chime in, but if you're at 800mv, I'd say you're getting plenty of fuel. I wonder if it's false knock... how many degrees of retard?

 

[djj624]

I literary heard the knock once. Iv also tried cruising on the highway in third gear and slowly rolling into boost with no luck. Iv seen knock anywhere from 2 on a very short blast all the way up to 11 once (eek did a compression test right after that one and got lucky). Anyways I'm trying to get this sorted out so I can have some fun with this car. Going to be installing 42lb injectors and a tt chip tomorrow

Galaxy S7 Edge

 

[Grand_87_national]

How much boost do people typically run on 91-93 octane before getting knock? Might be time to think about alky. It sounds like you're getting enough fuel, but it's pulling a lot of timing, probably due to overboost, I would guess.

 

[djj624]

I'll try changing the springs in the wastegate to give me 13.5lbs instead of 16lbs.

Galaxy S7 Edge

 

[1984 t-type]

Think most run about 18lbs before going to alky, have you tried turning up the fuel pressure so your at 42 line off

 

[Grand_87_national]

I'll try changing the springs in the wastegate to give me 13.5lbs instead of 16lbs.

Galaxy S7 Edge

I would, better to be safe. I don't know what fuel you are using, (assume 91) but you're probably pushing the limits of it right now. See what you can do after the chip and injector swap.... get a boost controller so you can move up in slow increments.

 

[djj624]

Going to crank up fp after injector and chip install. Gas here in jersey is 93 octane

Galaxy S7 Edge

 

[Grand_87_national]

Going to crank up fp after injector and chip install. Gas here in jersey is 93 octane

Galaxy S7 Edge

Ok, we have 93 here in the Kansas City area as well, can't understand why it would be detonating.

 

[DavzGN]

What chip are you currently running?

Sent from my XT1650 using Tapatalk

 

[djj624]

Stock chip.

Galaxy S7 Edge

 

[Sweet6]

stock chip probably has higher timing than it should. At least from what I remember. Might be a good idea to get a TurboTweak chip.

 

[djj624]

Well swapped out injectors and installed tt chip, also dropped boost down from 16.5/17 to a clean 15 and I'm getting o2's in the high 700's and no knock. Although I am getting a major tapping noise but I know that it from the egr I reinstalled with the busted gasket, that will get fixed tomorrow.

Galaxy S7 Edge

 

[Sweet6]

15lbs is good for 93. I know some say they can run more but might depend on intercooler and weather.

 

[Grand_87_national]

Well swapped out injectors and installed tt chip, also dropped boost down from 16.5/17 to a clean 15 and I'm getting o2's in the high 700's and no knock. Although I am getting a major tapping noise but I know that it from the egr I reinstalled with the busted gasket, that will get fixed tomorrow.

Galaxy S7 Edge

Good deal! Timing may have been too aggressive with the old setup.

 

[TURBOPOWERED68]

I could never go over 13-15 psi with 93 even with the TT chip.

Tapping noise -- At idle? don't forget to check the belt tensioner. Mine was tapping a LOT.

 

[djj624]

Didn't start the tapping till after I installed the injectors. When I took the egr valve off the gasket stayed whole but was brittle as hell, I'm thinking this is my tapping noise but will find out tomorrow when I replace the gasket.

Galaxy S7 Edge

 

[hotairgnx548]

Didn't start the tapping till after I installed the injectors. When I took the egr valve off the gasket stayed whole but was brittle as hell, I'm thinking this is my tapping noise but will find out tomorrow when I replace the gasket.

Galaxy S7 Edge

why don't you put more infomation than 87 turbo regal so someone can tell you what to do? john