the bummer is everyone wants to spend money on go fast parts first and not KNOW where they started from. My buddy let me use his Wideband from the moment I fired my 7MGTE up. Tons of people told me what I would need to do and I didnt NEED to do many of the things most people say is REQUIRED.
If you do one thing BUY A WIDEBAND O2 sensor. You will never regret it.
I had the benifit of a friend to advise me to spend money on what I needed first. Granted my goals were different (higher HP than 300) but mine did + 300 from the day I started it.
After seeing first hand and using a Wideband from almost day 1 I still have yet to NEED a fuel controller.
Let me first qualify that all of this stuff was done on my highly modified 1971 Datsun 240Z with a 7MGTE in it. Here are the mods that netted me 335 to the rear wheels with NO tuning what so ever.
1. A 3 inch custom mandrel bent exhaust.
2. A full Garrett/Turbonetics T4 60-1 turbo with an ebay 35mm wastegate (tial copy) set to 10 psi
3. Huge intercooler 24"x12"x4 inch core (ebay)
4. 3 inch plumbing to and from intercooler
4. Lexus AFM
5. A walbro fuel pump with a relay run with a huge 4 gage wire to the fuel pump to make sure there was no drop in fuel pump voltage.
Remember I have done NO, I repeat NO mods to fuel tuning or with a fuel controller, ALL WITH STOCK 440 INJECTORS.
Before you jump my stuff let me explain. Since the Z/7M swap I have purchased an 89 turbo MK3 that is bone stock except for some washers that the previous owner installed on the turbo wastegate. I am planning on documenting my HP and Mods to show the cheapest safest way to make more horsepower notch by notch dollar by dollar until about 550RWHP. Since I have already come close in the Z with the 7MGTE I believe I have a good idea of the first best mods and the best bang for the buck. Here they are in the order I will change them on the MK3.
1st, In my opinion the easiest very cheapest thing is obviously the wastegate. You can shim it or you can do something much more easily adjustable like this (still looking for photo).
2nd, in my opinion, should be the exhaust.
3rd, should be the Intercooler plumbing with an obvious Ail filter upgrade. The intercooler seems to be pretty efficient up to around 350+ RWHP in my opinion.
4th, a Lexus Air flow meter. Remember I have a Lexus AFM and no 550's (yet) with excellent results and perfect A/F ratios, this will suspend fuel cut a solid measure above the stock AFM.
And most likely a fuel pump when the need arises.
All the while monitoring Wideband O2 sensor, Intercooler outlet temps and fuel pressure in that order. In my opinion the stock CT-26 should be good for 300RWHP no problem, how long it lasts will depend on how well it was treated previously and how hard you beat it later.
I hope to prove my supositions with testing and Dyno Data. I will post my findings here as soon as I do each test.
