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I have a lagging/backfiring conidtion that I was wondering if someone could help me with. Here is what is happening: I have notice that like when i am accelerating hard on the highway in third gear(also does it in other gears) at WOT it hesitates, lags and has been backfiring some.(only does it under WOT) I was unsure what the cause could be. Here is what I have done to the engine.<p> Vortech R trim supercharger(10 lb pulley), trickflow twisted wedge heads, lunati cam, 1.6 rockers, edel RPM u/l Intake, 70 mm TB, 73mm MAF, 30 lb injectors, Vortech FMU, MSD BTM(1/2 degree), 14 degree timing, AUTOLITE 3923 plugs(.35), BBK longtube Ceramic headers, etc.....I WAS WONDERING IF ANY ONE HAS ANY SUGGESTION ABOUT WHAT COULD BE CAUSING THIS ACTION. Could it be to much gas and it isnt all getting burnt?,to much timing retard?not enough gas?wrong fmu calibration?(PLEASE HELP ME SOLVE THIS PROBLEM so i can quite worrying about it....One more thing, will it hurt to run with the BTM at 0?(i have my rev limiter set at 6k and have never seen more then 8 lb of boost).
 

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What is your fuel pressure at WOT?? Could be too much or not enough. What's the FMU cal? Plugs should be good at .035.
As for your BTM, No way would I go to 0 with 14 initial on pump gas. Thats about 30 total. I would try to stay around 21-24 total on pump gas.
 

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I think 14 degrees initial is fine. I would drop the FMU for the 30 lb injectors and try it. 8-10lbs of boost is about the max boost for 30lbers. For the time being, make sure you have 93 octain or higher in the tank, and don't go to your shift point. Creep up on it and if you pass the point where it bucks, you know its fuel related. If you want to try it with no FMU, I suggest 18-20 degrees total, then you can creep back up on it. This is how I would set your BTM :

How to calibrate your BTM

Things needed: timing light, regulated compressed air source or squeeze bulb with gauge, MAXIMUM boost produced by engine.

1) Remove timing spout connector and start the car
2) Set base timing to 20 degrees (this keeps the engine from dieing while timing is being pulled out and it’s easy to subtract from)
3) Using the compressed air source; apply your MAX boost pressure into the BTM
4) Use the timing light together with the BTM knob to remove your desired amount of timing.
5) Reset base timing to previous setting

EXAMPLE:

With a base timing of 14 degrees (EEC is 16 degrees) your total advance under WOT is 30 degrees. Say you want to run 22 degrees total timing at maximum boost. The difference is 8 degrees that you need to remove. You have 12lbs of boost at max rpm. Now, you apply 12psi into the BTM while the base timing is at 20 degrees. While using the timing light, turn the BTM knob until the timing marks are at 12 degrees. You are done with the BTM knob now. Return the base timing to 14 degrees. Now you have calibrated the BTM to remove 8 degrees exactly at 12lbs of boost regardless of where the base timing is.
 
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