Need help with detonation trouble

Okay, so this weekend I finally got to Mike's Speed Shop here in Southern California and had all the stuff that I had, put into the SC.

Previously I had been getting detonation at part throttle and sometimes full throttle after installing a ZR Intake and rebuilding the engine at .040 over with the 95 pistons. I decided I should upgrade the fuel system and put in plugs and wires.

I bought:
36 lb/hr injectors
Champion double Platimum plugs (gapped at 45)
Magnecore 8.5mm
76mm C&L with 36/38 (red) sampling tube
ported some spare exhaust manifolds
one new O2 sensor

This was added to the stuff I already had:
ZR Intake
Magnaflow resonator
Flowmaster 40 (deltas)
255 lph Walbro
steel idler pulleys (not that it matters )

The cam sensor is fairly new, IAC was replaced not that long ago. Everything else is in normal operating status.

The injectors we took off looked like ***. One of the plugs looked kinda funky (some white ash stuff on it) and wasnt even in all the way (some compression leak). So we got everything in there and it ran smooth as a baby's butt, and got all the ic tubes tighter than a twelve year old. Took her for a spin (octane plug back in) and it started pingging again, no bucking, just the clicking noise. Took the octane plug back out and it still pingged (but less), again no bucking, just a little noise. I needed to leave so nothing else was done to it.

So this morning I figured I'd take a look at it again and found out that the hose that goes into the intake tube from the driver's side valve cover wasnt connected because the grommet was cracked so I taped it up and drove it to school. I got on it a bit and it pingged less, but it was still audible with the plug out (a very small ammount of pingging).

The car itself feels WAY WAY stronger and faster than ever before. But I'd like to run at full timing without the octane plug out.

I was thinking of changing out the knock sensor and if that didnt work, check the TPS. No codes or CE lights, but just out of precaution.

Suggestions and all kinds of help would be welcome!

If your suggestion wins, I will send you a mystery package through USPS with usefull stuff in it j/k

Al

plug

gap .45 ok that don't sound right ..did mine @ 54 n/a 3.8 calls for .44 but it to small @45... don't know anything about champion plugs or heat range .. but I would open them up a few thousand first ..

Just my opinion and you know how that is. They are like ...well eveyone has one of them too. Anyway I would find all vacuum leaks if any and correct and, from my experience at least, lose the Champions. They just don't run worth crap in a Ford. Not the Fords I have driven over 30 years anyway. Autolite or Motorcraft have always been dependable for me regardless of the stage of the motor. I'm sure there will be people who like Champions but I have had 3 cars that I had rebuilt or tuned up go to crap in minutes with Champions. Changed them and fixed the problem. I hope that's all it is for you. Again just my .02.

A great week all.

Anyone have a number for Dr. Fred, or know which spark plugs he uses on his high compression engines??? I think the problem is the fact that the 95 pistons on an earlier engine bored to .040 over is too much. I will definitely be losing the champions then.

Also, 45 is what the people that use the Magencores 8.5 gap there plugs to.

Al

Either try the stock plug AWSF34PP @.045 gap or maybe some Denso IRIDIUM plugs.

I have only used the Denso plugs in my 95 ACURA Legend that I used to have and they were great but expensive. When I changed them at 100,000 miles they still looked brand new. I have heard fellow SCers running Densos because of detonation and they took care of it.

On my 90 and 95 SC I have always used The stock Motorcraft AWSF34PP's with great luck. No detonation on either car. My 90 is slightly modified and my 95 is stock until next month. It sounds like you have taken good care of the fuel needs. I have heard nothing but complaints about the Champion Plugs in SC's so I would ditch them.

I would also check the fuel pressure to make sure that it is up to spec. even though you just put on the new parts.

Just my .02

Bob

Cool, so champion is junk. I will try to locate the densos, or if that fails, the stock 94-95 plugs since it is a colder plug than a 89-93. Also, will be trying to change the knock sensor. any one else have any other suggestions besides these?

Al

I found the part number for the Denso Plugs for the SC. Denso Iridium IT20. I have so much info on these beasts that I have a hard time finding it sometimes.

I have to tell you that on my 90 when I put the 10% + pulley on I blew off quite a few of my vacuum fittings because of the increase in boost. The rubber was worn and stretched out on several boots and etc... The one on the back of the plenum that runs to the fuel pressure regulator kept blowing off and causing detonation. The air/fuel ratio was leaning out because the regulator didn't know to increase the fuel pressure because the vacuum hose was off. I replaced the elbow with a new one from AutoZone and it hasn't blown off since. The car literally felt like it lost 25 HP when it came disconnected. Find those pesky vacuum leaks and that should help also.

Bob

The vacuum lines/fittings were all inspected (trust me, Mike and I are anal about stuff like that) and are in good condition. One thing I havent done is check fuel pressure and see if its going up with boost. Also, the fuel here is 91 octane ONLY. That, the plugs, and a few other stuff is probably what the problem is.

Al