450-500 at the flywheel or wheels? Either way you would be right at the top of the 42# injectors. I would go 60# in case you decide for more power later. Pro-M can sell you the injectors with a matched MAF.
I thought 88's where MAP/speed density, have you converted to MAF?
Do you need a ECU for it? If you can afford it yes. There are the ways of getting around it like we all did in the old days like getting an enriched MAF that gives you 10% more fuel than a NA curve would. Running a FMU (though I have never had good success). You could also take some timing out of the distributor or run a boost retard on your ignition box. Would probably just be easier to buy a base model tweecer for $300 and throw a log-able wideband O2 in it for confirmation. Either way, without a way to tune the car, you will probably have to limit the amount of boost you run for safety.
I'm running an on3 kit on a stock low mile motor. I had the car professionally tuned with a Microsquirt ECU which eliminates the MAF. I am running low boost 6-7bs so i'm not near the numbers your looking for but i have 47lb ford racing injectors the car runs perfect.
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