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Because I had just came from another thread about a 383 crate motor in an OBDII truck. I skipped the first post and didn't see what year the truck was.
Regardless, a TBI spacer isn't going to do anything. An isolator will but again I don't know if they make one for us. Since most of the TBI trucks run rich enough to power a Honda Civic on our exhaust fumes increasing the pressure is only going to waste gas and reduce power. If the engine is popping out at top end then it might could use a little more fuel pressure to counter the drop of long, heavy throttle runs. But again, just increasing the amount of fuel absolutely, 100% doesn't increase power. Fuel is only the accelerant, without air the engine can't perform. Jam twice the fuel in and get half the power. In order to get power from the increase in fuel you need an increase in air. And a TB spacer does not assist in fuel atomization. Once the charge is pulled into the hot combustion chamber the charge will instantly atomize. Heat and fuel are like Mentos and Diet Coke. Alone they are stable but put them together and they instantly release energy by de-gassing(I think is the right term).
PROM writers are cheap. You can get a BURN1 from Moates for like $60, and the chips are $5/ea. I got an Autoprom for $200 that does everything: read/write/burn/erase/datalog. The TunerProRT software I use is free, and there are definitions available everywhere. I took the stock $0D 7427 tune and modified it for my setup pretty easily. Fuel/spark and 100 other variables that are editable within a stock BIN file.Please explain how he would tune his stock ECM with out expensive PROM writers, and a program to alter the fuel and spark tables.
Yes the stock '88 to '95 blocks are roller compatible, he will also have to add a cam thrust bearing in the timing cover or a cam plate. This is because with a roller can you loose the built in rearward thrust that the cam lobe profile gives you to ensure the cam is always in contact with the distributor gear.
Actually there have been many independent tests that show TBI spacers only help out in the upper RPM's where our engines rarely spend any time. Also they have been shown to be very application specific and do not always help out. And he is right about the higher fuel pressures not doing anything unless you tune the computer for the higher pressures. More over in order to get the most out of fuel pressure increases is to use a Vacuum Referenced Fuel Pressure Regulator. This regulates the fuel pressure based on how much vacuum is being drawn by the engine. The lower the vacuum, the more fuel it lets through. Higher vacuum requires less fuel. This has to do with the amount of fuel that drops out of suspension. At lower vacuum times, more fuel collects on the walls and port floor of the intake runners. Fuel burns best when it is well atomized.