Well I took the plunge a couple of weeks back and swapped on 454 tbi setup and threw the 750 carter in the trash. You might remember my "swapped to tbi on suday night....bad idea" post. I've come a long way since then but I'm still havin some trouble. Here's a quick rundown of my combo and then I'll list my problems.
350
305 heads unshrouded the valves (1.9,1.5)
comp 4x4 extreme 216,226 4.62,.480 with 111 lobe sep
rpm intake
1 5/8 shorty headers dual exhaust with x pipe
454 tbi with stock injectors not sure if they are 80's or 90's
747 ecm
external fuel pump (ford truck application 130 lph)Not mounted below tank.
I got the timing table worked out with the carb on just to simplify things a bit, I'm using a hybrid bin based on a 4.3 and a 7.4 bin just using the injector constants and adders from the 7.4 and filter constants from the 4.3

I got the part throttle nailed down pretty good. blm's in the 125 to 130 range It idles ok once it's warmed up and has had some time for the blm's to take over at idle. First problem is the iac just locks out at 145 park position after it warms up. It will take to surging fits from time to time. Once moving though it drives like a FI car should drive, wicked throttle response almost hard to take of without spinning the tires . When I lift off the throttle it starts surging every 2 to 3 seconds like the dfco keeps hitting and then letting off. It'll drop 400 rpms and then jump right back up to where it was before. I tried disableing the dfco it didn't effect it at all.
The next problem is wot. It just plain goes flat after 3600 and completely cuts out at 5000. It sounds like it goes lean, it smells like it goes lean but the !@%$%# O2 says its rich, pegged at like .900 and up. I've tried leaneing the ve curve as well as richening the curve. It did pick up a little between 3000 and 4000 with the richer setting but still cut out at 5. I'm lookin towards the fuel pressure droping off at high rpm's. As I said earlyer the fuel pump is not mounted below fuel level but I personally know of several people and several magazine cars that are setup like this with no problems. I did reuse the fuel filter that was on my carb which is almost 2 years old, so that may be my problem. Let me know if anyone would like to look at my bin.I'm not too worried bout anyone making any money off of it so I may just post it here.

Plan of attack
replace fuel filter
replace plugs and O2 ( she was runnin a wee bit rich when I got her runnin, like fuel was backing up on top of the throtttle blades a 1/4 inch deep so i'm sure they need replaced before i go any further)
Start screwin with stuff at idle
Then move to the wot stuff. (I feel like i'm in Iraq with a pellet rifle without my power)

Sorry this is intirely too long and if no one reads it thats fine It just helps me to get this all out where I can read over it and get a little feed back to make sure I still have my sanity.

 

Congrats on getting you Monte efi'd. I've got an 88 SS... got TPI on her.

I'm sure you've heard it before, but I'd start tinkering with some 350 bins with the injector constant set for what your running. Also I'd consider getting the proper gas tank for the car. It's not that much work to convert, having done it myself. I switched the return and vapour lines around (not sure if that was a smart move or not, but it works so far). My tank/pump is the Buick GN configuration, but I hear the Monte TBI tank works just as well.

Ernst

 

Yeah I considered swapping for the 4.3 tbi tank but just decided to do the external for money reasons, as well as being able to swap back to carb in a few hours if things went real bad, i.e. injectors were trashed or somthin. If the filter doesn't solve my problems i'm gonna modify my fuel pressure guage so I can mount it to the windshield for some full throttle action and see whats goin on. Thanks for the kind words helps me keep chugging along with this thing. I have already left one honda boy with his mouth wide open when i yanked out my laptop to do some datalogin. It makes it all worth it.