I have had the dreaded miss for some time now. I know I have a few things that need done to eliminate them from the possiblities. Anyone know what the plug gap to run on a supercharged set-up is. Also what is a good starting point for the fuel pressure - it is around 40psi currently. I have an MSD 6BTM i will be installing sometime this week (I hope) and have already installed an msd coil. It seems that there has not been any one major problem that has solved the issue for everybody. Like everyone else the problem is more noticable the hotter it gets and the bigger gear number i am in. It seems almost like a rev limiter that you can still accelerate with, but slowly.

Another problem i have is it runs good (except the high rpm thing) when it is cold, but as soon as it warms up (about 10-15 miles - depending on air temp) it starts loading up extremely bad like it is a stuck float in a carbed engine. It starts stinking of gas and blowing black smoke terrible (you wouldn't want to be a smoker and stand behind the car) and the fuel mileage is terrible (around 200 miles or less to the tank). Any Ideas before i take it into the Specialilty Shop?

Here is what i have

95Z Cnvt w/ 80000 miles

96 LT4 (from Grans Sport Vette) unknown internals
assumed to be stock, w/ 36000 miles
No Egr (standard for this LT4 engine)
No Smog-Pump (also standard for the LT4)

Mufflex Y pipe into 4 inch single into Spin-Tech dual 3 inch out
No Frigging ground clearance

Hooker LT w/ o2's installed and o2 harness extensions
No cats
High FLow Thermostat (180-degree)
52mm BBK tb
Adjustable Fuel Regulator
255 LPH plug and play pump with full 12 volt power
50lb injectors
ATI 9lb single intercooler Supercharger
Stock MAF with ATI MAF massager (no clue what this does)
Stock LT4 plug wires
ATI recommended plugs (AC, i dont remember which ones)
Fastchip programming (Ed Wright)
96 LT4 Knock Module (if this the module that is on the PCM)

96 LT4 Knock Sensor (someone told me this is the worng one
and will set off a code - which it has - i intend to replace it
this week as well. One of the engines had two sensors and
the other had only one - I think the LT4 had two sensors
and we only plugged in the one like it was on the camaro)

Mccleoud Street-Twin clutch (this thing is way too grabby, any
recommendations - it seems to be off or on and right off of
the floor)

Completely stock suspension and brakes (someday i'll put some
good brakes and susupension parts on)

MSD - 6BTM (where in the heck have you guys been mounting
these things?) any pics would help.

Grooved crank hub (keyed)
Stock wheels and BFG Comp TA's in stock 245 size.
Fuel pressure and Boost/Vacuum Guages (autometer)

Stock OptiSpark - but the 96 engine had an extra plug in for the
sensor on the crank - we just left this unused.

I'm sure i forgot a trinket or two but this thing is really bugging me. Thanks in Advance-

 

30-35 thousands is what I have always run on all the blower applications I have built, anything over that tends to blow out the spark unless you have one hell of a ignition system and I'm not talking about a MSD with a after market coil. If you were running a 4.6L Ford go with 25-30, literally. Best of luck!