3 Mod rule
 

Looking for some knowledgeable advice on this subject.
Here is the situation:
I am in the midst of replacing my stock twins with another low mileage set. And I am debating installing some of the parts that I have purchased for my car.

Current car:
93 VR
Downpipe
Free flow Bonez cat
STOCK cat back exhaust
Stock air box with the bottom cut out (PO, I just saw it as I was removing the air box)
NO pills in the turbo lines, my boost pattern is right on for no pills; 7/6/7
Stock ECU

Parts to install:
Petit cool charge intercooler
Apexi intake
Greedy electronic boost controller

Now, I realize that if I install the intake and intercooler that I am hitting the three mod rule, and need to look at installing an aftermarket ecu. But, while that is in the long term plan, I would like to hold off until next year.
So, my question is, with the boost controller, no pills, and the stock cat back, would I be safe with all of those mods, or should I scrap at least one of them until I go Apexi Power FC (or whatever aftermarket)?

Check this thread:
https://www.rx7club.com/3rd-gen-archives-73/stock-ecu-10-psi-myth-308996/

Mahjik, you are the king of threads!!

Ok, read through that thread a few times, still fairly confused. It would have helped if the link in the thread worked, to show the graph.
But, see if this makes sense...first I buy an AFR gauge (any suggestions? I have a Summit in my first gen), second, I hold off on any more mods until I do that, but also should probably not install the intercooler until I can do the Power FC at the same time. And, if I am going to do that, I might as well save up and get the RB dual tip cat back and do this all at once. No sense paying for tuning, just to add something else six months down the road.
Any thoughts?

Basically, you can add what you want as long as you are able to control the boost and keep it to 10 PSI. I ran:

Intake
DP
Hi-flo cat
Catback
Blitz SMIC

on the stock ECU for about 2 years. No issues.

never understand why people mod these cars w/o raising the boost. the best power gains comes from increases in the psi;s. if you are gonna spend 2k in mods, just spend an extra 300 for injectors and you will make 80 more rwhp. Proven. Now that makes sense.

It's about money and time Matty. A properly modded FD can't make 300 rwhp (reliably) for $2000. With mods and higher psi, you need an ecu upgrade, along with a bunch of other stuff.

As far as 10psi goes, I would bet that a well modified and tuned FD could easily make 280 rwhp at 10 psi.

You should port your wastegate while your twins are out. You can install all of your mods safely, but you might get boost creep as most do.

Just an air/fuel gauge is nearly worthless in terms of calculating an accurate AFR. The only way to go is a wideband, companies like Innovate, FJO, etc. make good kits. Once you get a wideband, then a PFC, datalogit, and maybe bigger injectors can really unleash some potential.

AHarada, and adam c, agreed, and that is the path I want to head down over the next few years. But, I have to do this in stages, otherwise I will be paying an attorney for the divorce proceedings. Actually, if I would sell one of the four RX's in my driveway, she would let me do whatever I wanted to the 93. It's actually the only car I own that she likes. But, I digress.

Thanks Mahjik, this was the info I was looking for, and I didn't even get flamed.

I ran PFS intake, PFS IC, DP, Hi flow cat, RB catback, with stock ECU for a while with no problems. Just keep the boost at 10 PSI. I used Hallman boost controllers (Damian's Mod).

Since then I have gone from M2 stage III to PFC for the ecu and run 12 PSI.

Agreed. You can get an extra ~60whp from these cars relatively cheaply at 10psi. In fact, $1000 should be plenty: Cheap Bastard intake ($80), Home Depot boost controller ($20), used downpipe ($100), used RB exhaust ($400), used SR/Blitz/Greddy SMIC or the like ($400). (I'm not all that convinced that a y-pipe or non metallic cat are worth it.)

I pretty much started with the mods. Of course, power is addictive and I am now spending money on my way to 400whp...

I don't see creep being an issue at all with those mods... as long as he stays with the bonez hi-flow cat. He's opening the intake side, not the exhaust. And note he's still running the stock cat-back.

I am not going to port the wastegate at this point, I am trying to get a low mileage set of twins reinstalled right now, see my other posts with that problem.
But, right now, I would like to install the SMIC, the boost controller, and the intake. I am going to keep the stock catback for now.
Future plans include a set of BNR's and an RB catback. At that point I will add the Power FC and get it tuned.

I am going to assume you had an after market radiator as-well?

Not at that time.

Any reason why?

Didn't need to. Simply adding a new radiator doesn't automatically give better cooling. Had I increased the amount of air coming in the front (i.e. aftermarket bumper or the shark mod I eventually did), then I could take advantage of adding a radiator with a larger capacity.

The only problem with the stock radiator is that it has plastic end tanks. Other than that, it's fine.

FWIW, I'm now using a radiator which is slightly larger than a Koyo (and I increased the front opening for more air with the shark mod). However, the car is being made to handle the track. If it was just a street car, I would have gone with either another stock radiator or an stock replacement aluminum radiator.