Well, first the mods.
3mm Atkins "mild" streeport S4 13BT
Walbro
Rtek 1.5
Stock 550'sd all around cleaned 2 years ago
Aeromotive 1000 FPR set to around 38psi
Stock rebuilt S5 Turbo
No fuel management like SAFC or anything.

So.
Will the Stock ECU handle it and will the injectors hold up?

Has anyone done this before?
I ran 10psi via MBC before on stock port. I'm assuming I'll probably have to turn that down.

I'm more concerned about the fuel situation. Anyone have a known ok PSI to run?

 

You should upgrade to at least 720's on the secondaries, but your would need to upgrade the rtek to the 1.7.

 

It'd be smart to upgrade that 1.5 chip to a 1.7 and then go ahead and throw some 720's/750's in the secondaries.

The stock ECU will be just fine, even with a big streetport.

 

For a streetport...

I'd say get some 720cc secondaries, get your 550cc primaries cleaned and balanced (2 years is a long time ), and upgrade to RTek 2.0. Tuneability for the win..

 

You guys think if I left it at stock 5/6psi boost I would be ok?

I won't be able to get 720's and an rtek for a little while.
I'll probably go with 1.7 since it's a cheap upgrade since I already have 1.5.

Then I'll save for Haltech.

 

I think you will be fine with the 1.5 it will pull the timing. You didnt realy say how much boost you will be pushing. Lets say 10psi but your not going to get anymore without an TID If you ran a upgraded pump and 42 to 45psi base on the FPR I think you will be able to make it. I would personaly stay more around 8psi without 720s.