Sykopny

I have a fresh 331 installed that is now somewhat broken in with 700 miles on it. I have the timing set dead on at 13 degrees and the plugs gapped to .045. I have tried the fuel pressure at 38,39,40,42,44 PSI, but I am getting pinging under heavy load when I mash it to the floor. Should or shouldn't I keep the vacuum line to the regulator connected or disconnected? It is a California car and I use 91 octane with octan booster and it still pings. there is no misfire, I've checked top dead center and everything is dead on. Any help?!?!?!?!?!?!?!?!? If you need more info, let me know.

luckythirteen13

do you have oil pressure?
did you tighten/install the rockers properly?

Big5.0.13.7sec.

DONT WASTE YOUR MONEY ON OCTANE BOOSTERS!!!! THATS SOME GAY *** ****!!!!!!!

Sykopny

Getting 45 psi from an Autometer, so yeah, I've got pressure and yes the rocker arms are adjusted correctly. I have a Fluidampner, so I know timing is where it's at. I've checked top dead center 3 times and it's dead on. What would happen if I left the regulator vacuum line disconnected? Where should I set my base fuel pressure at idle with the hose disconnected? I have a waterflow restrictor (blue) and the electric fans take care of the temp. It's runs at 175 on a hot day in california in traffic also, so it's not a heat issue. I have a set of Cometic headgaskets & Twisted Wedge heads with ARP studs torqued to 84 ft lbs, so it's not a headgasket and I just installed new TFS set of valve springs and seals to withstand a .600 lift. I was thinking more along the lines of the camshaft not giving me enough manifold vacuum to the regulator. Any more thoughts. As you can see, I've exhausted every source. I also have an MSD billet distributor and MSD 6A spark box, Screamin Demon coil, 9mm wires, Accel u-grooves that I tapered the edges on and gapped to .045. Does the MSD distributor have springs to adjust retard? Someone help!?!?!?!? Again, if anyone needs more tech info, I've got it.

Sykopny

Why is octane booster gay ***$&%!?

Dbeck002

this may sound stupid but did you calculate what compression you are running? you may need to use 93 octane if its more than 10:1 (correct me if im wrong someone). other than that i would guess since you replaced all those major things this problem is perhaps a very simple one that is just under your nose, look in places you wouldnt think the problem would be... happens to me a lot..

Sykopny

I stayed with the stock 9:1 compression so I could runs a Blowzilla with 13-18 PSI when I find the detonation problem. It still pinged when I put the gay ***#*$! 104+ booster in it also. What would happen if I disconnected the vacuum line to the regulator? Wouldn't it stay rich and not lean out? Are my stock fuel rails not flowing enough pressure? I've heard about cylinder #5 having a lean problem. Any truth to that? Thanks for the help guys!!!

Dbeck002

ok since you are running high octane the pinging might just be the engine running lean. What size injectors are you using? and is your MAF sensor programmed for this size? If so, make sure you hear your fuel pump when you turn the key on engine off.

one more thing it 'could' be your timing but i really doubt that as you are already running high octane with that booster. just incase i would recheck the timing again.

roundman

drop the timing back until the pinging stops before you damage the engine. with the heads and cam combo, you may be getting higher cylinder pressures which are contributing to the pinging even if the compression ratio is 9.0:1. and with that ignition, you should be able to open up the plug gaps to .052" or so and still get good firing and a bigger spark. stock fuel pressure is about 39 and you should keep the vacuum hose connected to the fuel pressure regulator so that it can function as designed, which is to maintain a fuel pressure to match engine demand via reading the vacuum signal.

Sykopny

I've dropped the timing all the way down to 11 degrees, but at that setting, the pinging is gone, but the car lags and has a long crank when starting. I have 30lb injectors installed, so I know it's getting enough fuel. Also, I almost had a POS Neon turbo take me out the other day. Does anyone out there recommend going with a bigger cam, like a TFS stage 2 w/.542 in./.563 in. opposed to .512/.512.? I feel the low end torque, but it feels like it is being held back. Mabe I need to upgrade to a 3 inch cat back system. Should I go with a bigger plug gap? Keep the ides coming and I'll keep giving info till I find it. Thanks again guys!!!!

By the way, the MAF is calibrated for 30lb injectors.