302 bogging down with EFI

[harleyabarton]

so i have a brand new 302 from blue print ran it natually asperated and it made 330 horsepower to the crank! pretty good for a old bronco but i wanted to supercharge it (vortech). so i did and while installing it i installed a msd dizzy and ignition box and coil. i installed a fitech 30004 (the supercharger version)
after getting everything to finally work (kinda it still randomly dies) it now runs and idles great and will rev at WOT great! i have a locked out distributor set to 34 degrees at 3500 rpm. the thing eats gas like crazy and smells like unburned gas... i mean like i had a half a tank of gas yesterday and all i did was idle it and set the timing for about 10 minutes and it used the whole half tank!!! but it sounds great and runs like a normal engine!

only problem is it has NO power. if i had to guess its hitting like 100hp at maybe 1600 rpm then just diving... i can get it to get into all gears but if you try to start it in first and you dont jam the gas pedal itll bog down as if it has NO gas. im so confused! is this a timing problem? are spark plugs bad? or is it just the ignition box? or the fuel injection? i dont understand why it's great and revs perfect without it in gear and then as soon as it has load it just doesnt wanna move out of its own way!

 

[pcf_mark]

I am not a Fit-tech user but EFI is EFI in a general way.

What is your fuel pressure?
Do you have a wide band O2? What is it reading at idle and cruising down the road?
What is your timing map look like? Any chance you have boost retard?
What does your timing light tell you the timing is at idle versus the FitTech? If you rev it to 2500 what does the timing light tell you versus the map? It is possible to get the offset wrong and have some crazy timing.

 

[harleyabarton]

I am not a Fit-tech user but EFI is EFI in a general way.

What is your fuel pressure?
Do you have a wide band O2? What is it reading at idle and cruising down the road?
What is your timing map look like? Any chance you have boost retard?
What does your timing light tell you the timing is at idle versus the FitTech? If you rev it to 2500 what does the timing light tell you versus the map? It is possible to get the offset wrong and have some crazy timing.

is it really possible any of this could be the problem?? to be honest i half expected this to all be a flook ahahah youre telling me i may just have to tune it? ahahah

i could look into that stuff. i do have whatever O2 sensor they gave me wich i belive is wide band and it tight into a socket i welded into the exhuast right after the collector. its welded facing up. is that a problem? normally the afr reads like 12.6 but back when i couldnt get it to rune it red like 18
its possible there is a leak in the weld it was done under the car so it was kinda hard to reach.

um the timing at idle is about 18 and i set the spark map to about 18 as well and then at 3000 its about 33 and i set the map to be at about 33 as well and then at 6000 i set it to 36 even tho ive never pushed the engine to 6000 yet with the supercharger..

by boost retard im not sure what you mean? I am new to using a supercharger but if youre talking about a vacuum advance. i do not have a vacuum advance and my distributor is LOCKed out.

 

[pcf_mark]

Your timing sounds a little high (I would have said 12-14 at idle but you must have some cam in it to make 330 hp) and that can make the exhaust stink like it is rich but it is really just poor combustion. I would do a cylinder balance test to eliminate a dead cylinder(s) causing low power and stinky cylinders. Pull one plug at a time and see the rpm drop. Say it is 150 rpm. Put that wire back on, going to the next cylinder. Do all 8 and if the rpm drop is not very close for each cylinder start figuring out why. Maybe you have a bad box, distributor or burned plug wires. Is your timing map "normal" - all the data points around 3,000 are around 33 or are there rows a few spots away 20 or something goofy?

Assuming that is all good this info would help tuning:
Tune it so it runs good without boost first. You need to log or post your O2 readings to determine if your fuel is overly rich. If your fuel pressure is off it will show up as rich fuel mixture on the O2.

Can you share the O2 readings and timing from controller at
idle in park
idle in gear
going down a level road 1,500 (or lowest rpm in high gear) with steady throttle
2,000
2,500
3,000
This should plot a low load fuel and spark curve and my bet is you are way rich like 12:1 and it is putting the plugs out killing power or your on a part of the fuel or spark map that is incorrect for your combo.

You may need to jump to a fit tech user group for detailed tuning but with the above data points it set up it should run decent. No promises on power but it should get you started.