gx pistons

[redlinesohc]

hi need some help i have a d16z6 with gx pistons and stock camshaft ported head with all the usual bolt on the problem is at part throtle i keep getting detonation this is with only 10 degrees timing is it possible to solve this without going to larger injectors i have an adjustable regulator but is that the right way to solve it. any advice would be helpful thank you

[sqmark]

The Gx pistons are only 27mm Compresion Height which is 3mm short of what it should be. Get some expensive 140mm rods or get Y8 pistons.

Er OK complete rubish sorry got confused, Ignore this

[redlinesohc]

what?

[sqmark]

Sorry, thought you mean't HX pistons.

What compression and fuel you running?

[redlinesohc]

figure it is at about 12.5 to 1 and fuel pressure is at 45 psi

[Calesta]

Your compression should be right under 12.0:1, assuming that you're running a standard head gasket and you haven't milled the head. The proper way to fix your detonation problem would be to have the fuel curve tuned on the dyno- that way you're always running the proper air/fuel ratio, and you're tuned for maximum power. You could do this with a Hondata S100, a VAFC, or some other piggyback tuning device. Things like adjustable fuel pressure regulators are only going to be able to change your fuel spray the same amount across the whole rev range, so it doesn't do you much good as a tuning device.

You could always turn up the fuel pressure some and spray more fuel, or you could pull your timing back... but both would probably cause you to lose power in the parts of the rev range where you weren't detonating before.

[transzex]

high compression means LESS ignition timing.

Dyno tuning is gonna be the only way, alone with a steady diet of 93 octane.

[kyosoeg6]

high compression means LESS ignition timing.

Dyno tuning is gonna be the only way, alone with a steady diet of 93 octane.

man i wish i had 93 pump gas

[FMYStreetRacer]

i would be very interested to see what you come up with. i might be doing a build with some pm7 pistons.

[redlinesohc]

i understand that it needs to be tuned but do i need a freakin standalone to do it

[transzex]

nope, never need a standalone.

Socketed ECU and a burner, about $100.

[redlinesohc]

ok what sort of program my friend burns chips what is it that i need he has stock b16 programs would that work or is it a custum thing thank you for the response.

[FMYStreetRacer]

when i was looking around to see what chip i should run i was told that the b16 program is the way to go, ot atleast start. it has more fuel and less timing advance.

[transzex]

why not that a stock P28 map and tweak it???

add 10% fuel, cut timing.

www.pgmfi.org

[littleone]

If the fuel and timing does not help eliminate your detonation a "wilder" cam may help. More duration and overlap will bleed off some of the static compression.