Heres my RX7's current mods,I need help with the new ones though!!
 

Ok,so one of my cars is a 87 Turbo II.I have a greddy blow off valve,turbo timer,boost control,custom intake,Kevlar race clutch. Ive already put the money down for a new down pipe w/cat,HKS Cat back,and Im going to UPGRADE to a BIGGER Turbo (THIS IS HAPPENING IN ONE WEEK!!).What kind of HP can I expect from this (I know I left no turbo specifics,but just a ball park figure),what kind of 1/4 mile.What should be the next upgrade.I want this car to be a sleeper ass kicker.it only has 80k miles on it.So,what are my next mods??Thanks for helping me out
adrian

just make sure you got the fuel to go with the mods :) cuz not enough fuel makes bad things happen :) lol

So,Fuel pump and/or injectors?

probably both, im not a turbo expert, but i know with a bigger turbo/exhaust and the other mods you listed, you need more fuel or the engine wont last long, probably have to wait till a little later for the really knowledgable turbo guys to come online :) im just a lowly n/a boy lol

As soon as you add on the exhaust your going to start running lean and boosting past the limit on the ECU resulting in a fuel cut. You'll need to rewire the fuel pump, or if you are going to a bigger turbo, use bigger secondaries. A method of controlling the extra fuel will then be needed. Wether it be piggy back like a S-AFC, or a full blown ECU like a Haltech.

As far as a ballpark figure, depending HEAVILY on the turbo you choose:
FWHP
Stock turbo: 220-240
Hybrid turbo: 240-300
T04 :D : 280-400

I'll jump the gun and say you'll run around 13's, depending on turbo and fuel delivery. But without any fuel mods or FCD, once you go high on the boost, your motors gonna pop like a 16 year old on prom night.

The cat's gonna choke you, but you're talking about a high 13-second 1/4-mile car at the very least.&nbsp In the ballpark of a minimum of 250hp at the flywheel...&nbsp (My numbers are usually VERY conservative.)



-Ted

Who Makes an upgrade ECU,or should I have one Made for me?The only reason Im still going with a cat,is so I pass CA smog.Otherwise I wouldnt.

My weakly grasped understanding on this was that rewiring the fuel pump is only done to ensure that it is receiving the correct voltage (6v at idle, 12v otherwise). The above quote makes it sound like it IMPROVES on the existing fuel pump somehow. Why is it automatically assumed that the pump needs rewiring? I would have thought that if an exhaust raises boost dramatically then a bigger pump and injectors (and I would say fuel rail if I knew what one is - which I don't!) would definately be need.
My reason for being concerned about this is that I was planning on achieving around 9psi of boost (S4 currently stock 5.5psi:( ) and am assuming that the stock fuel pump will be able to handle this ok as the S5 runs about 7psi stock with the same pump (?) and fuel cut is at 8.6psi so 9psi can't be overly dangerous can it? I am only lightly modding the car (exhaust, FCD, and such) as I really want (need) to avoid having to do all the fuel stuff (lack of money). Will I be OK with these assumptions do you think?

I guess what I really mean to ask is: whats with this "rewiring the fuel pump" business?