Calabrio

I have a bone stock, '87 Turbo II.
The exhaust system needs work, so I plan on replacing it with the Racing Beat RevII exhaust system.

I don't intend to race this car, nor do I have high horsepower goals for it.
Other than the Fuel Cut Defender, do I need to to do anything else to the car to make it a reliable street car?
Or other mods necessary or highly suggested?

I did intend to keep the car as "stock" as reasonably possible, or at least make the mods period correct.

Turbonut

iTrader: (1)

See what the others recommend, but I'd go bigger fuel pump and 720 secondary injectors.

j9fd3s

iTrader: (3)

what happens is that when you put a big exhaust on the car, the boost goes up and it will hit fuel cut. you then have two choices, lower the boost, or remove the fuel cut.
to lower the boost you can add restriction in the exhaust, a converter works well here and gets rid of the smell.

or you can buy an FCD or change the ecu or something.

DR_Knight

iTrader: (23)

The real question is what are the air fuel ratios going to be. Other than the advice given, you’ll need to check for yourself with a wideband Afr gauge or data logger. Without knowing your Afr’s, you’re in the dark and playing a guessing (more like assuming) game.

Aem uego units are inexpensive, but the sky is the limit.

diabolical1

iTrader: (3)

but doesn't that still leave the question of what could/would he be able to do about it?

j9fd3s

iTrader: (3)

when the boost goes over 8.25psi the ecu shuts fuel off...

DR_Knight

iTrader: (23)

with the fcd op proposed?

DR_Knight

iTrader: (23)

I’m not trying to debate. Simply saying if you’re modifying a turbo car, you really need a wideband Afr gauge to know how your car reacts to mods.

long story short, I always used my aem uego. My buddy didn’t have a wideband and was modifying his sr20 s14 so I loaned him mine over 2 months. I continued to drive my car as normal. I reinstalled my wideband and afr’s were showing stupid lean. I go into the safc to add fuel and no change. Change the fuel filter and it went back to perfect. Oh the fuel filter had a restriction. You really need a wideband to know what is happening. That’s all I’m saying.

yes you need a fcd. Yes, you should run a rtek ecu with larger injectors, the rtek has other positives. Fuel pumps original, why not upgrade it. Why not rewire the fuel pump to a new relay.

I mention rtek as it keeps the car basically stock so you don’t have to go crazy, however they’ve been discontinued for years so only hope is on your side when trying to find one used set up for the proper injector sizing. Possible piggybacks to get the tune close to perfect would be a safc. Or a standalone ems is an option but not so user friendly.

Stussy

I have this exhaust, you chose a good one. When installing this exhaust, it kind of leads you down a rabbit hole. If I were you, I would look for a RTEK ecu. This has a built in fcd, and will work better. I have the RTEK 1.7. with this, the secondary injectors need to be upgraded to 720cc to prevent it from running lean. A very good mod to do would be to port your turbo waste gate. The stock turbo can not get rid of the air as easy, and the boost will creep up untill the engine blows. I'd also invest in a afr guage, so you can read where you are at. One thing that I bought, but haven't installed, is a Apexi NEO. This will allow me to control the fuel even more. A bigger fuel pump never hurts, and is fairly cheap.

I'm in the same boat as you keeping the car semi stock. I don't want big hp either.

I've heard a lot of bad things with FCDs that's why I went away from it. Dr.Knight also mentions good points of mods to do, most fairly cheap.

j9fd3s

iTrader: (3)

the stock FD fuel pump is a nice upgrade, you get more headroom, but its not so big that it overwhelms the fuel pressure regulator at idle.
actually depending on how much boost and what AFR you're trying to run the stock turbo pump is fine.

the little in tank filter sock, if it hasn't been changed is an ND number, 952-0043

you get bonus points for checking the voltage at the pump. it should be within about 0.5v of battery voltage. if there is more voltage drop than that it needs attention (ignition switch, grounds etc)

Calabrio

That's the rub, I'm not really all that interested in more power. I bought the RevII just because it was complete and I figured it'd have the best residual value on the car.
I'd be happy with 200hp, so long as it doesn't blow up the engine some how.

Racingbeat doesn't have the FCD any longer, HKS seems like the only available option.

As mentioned, I really don't care about making power, I just want to avoid self-destruction. Racing Beat only mentions a FCD but I get the impression it's still a inclined to destroy itself.

WondrousBread

Others here have more experience with turbos so they will correct me if I'm wrong, but I see no reason OP even needs the FCD if he doesn't want to increase boost.

All you would need to do is port the wastegate out for better flow (there's a guide on Aaron's website). Then it should still open at the stock spring pressure and prevent the car from overboosting. Alternatively get the manifold welded for an EWG and use that.

The FCD prevents the car from cutting fuel when it hits 8 psi. If you never hit 8 psi because you've ported the wastegate, I don't see why you would need the FCD. Keep in mind you could still install one, but the FCD will not prevent you from running out of fuel, which is why I mention just keeping the boost way down.

Again, someone else may correct me here and you should listen to them if they do.

Natey

iTrader: (19)

I can't really say about the REV 2, but I put Racing Beat True Duals on my old FC (it was a 91 NA). It looked shiny and sounded great...but holy **** the RB stuff was heavier than stock.

Nosferatu

The original Rev2 exhaust built by RS*R was heavy wall mild steel...that thing was heavy compared to the stainless version.

j9fd3s

iTrader: (3)

those are also 80mm instead of 70mm

Dak

I don't have personal turbo experience but IIRC from what I've read on here over the years is even ported the wastegate on the S4 turbo will struggle to keep boost creep under 8psi with a 3" exhaust like the Rev II. Safest bet is a wideband, fcd and some way to add fuel for the increased boost.

Turbonut

iTrader: (1)

If you're not concerned with performance, a little counter productive, but just put a reducer in the exhaust.
Believe the factory size at converter flange is 2.25", so just install 3" od with a 2.25" id hole into the system.
They even make tubing 3" od, .375" wall, 2.25" id, just slide it in.

DR_Knight

iTrader: (23)

Or ask the question why go with the rev ii exhaust if a restriction is going to be added anyways.

Rhetorical question, but are you sure you want to have a stinky rx7? High flow cat can help prevent overboost.

2.5” down pipe would be more restrictive than the 3” rev ii.

racing beat N/A catback would be more restrictive than rev ii.

don’t quote me on sizes as it’s been a while since I’ve looked at racing beat’s exhaust components.

RXSpeed16

iTrader: (41)

It's kinda hit or miss. My S4 turbo with full Rev II was able to prevent creep below 10 psi. The problem comes when you're trying to push 11-12 psi. More power = more exhaust to deal with.
The issue is stock timing maps above the fuel cut are sketch since they were never meant to be used. Rtek 1.x pulled some timing up there but kept stock fuel maps.

Been there. Stock exhaust has rusted out and there are no oem-style replacements. Might as well get something with good resale value.
+1 for a cat or exhaust restriction without an FCD.
Pulling the turbo and disassembling is a pretty big job. Especially if it's the first time it's been apart.

Turbonut

iTrader: (1)

Just wanted to add, my experience with the RB turbo exhaust system, a converter would need to be custom made to fit into that system.
Also, with a 3" exhaust, a 3" in/out converter, don't believe that would cause enough restriction to keep the boost down, but if one
were to reduce the in/out size of the converter, it would work and keep the terrible exhaust odor to a minimum.

The other question, is that replacing the RB silencer with a converter, what that do to the sound quality?

j9fd3s

iTrader: (3)

if anything its a little quieter. putting a cat in the RB system is, or must be a California thing, i know a bunch of people that have done it

Turbonut

iTrader: (1)

Years ago, had the original RB Turbo system mufflers and modified the Y pipe to use with the factory stock cat, minus the precat,
had the system on the car for 2 days, couldn't stand the drone inside the car. Maybe just me.

WondrousBread

Mine is similar, NA with stock manifold, no pre-cats, high flow main cat, then adapted to a RB REV TII catback.

Definitely some drone at crusing speeds. Sounds great when getting on the throttle but it's a bit much when I'm just around town.

Keep in mind my car is NA, a turbo will dampen some of it. If I were doing it again I would work a cat into the downpipe section, and then keep the stock REV TII silencer.

ColinShark

Once you are running more boost, there is a giant snowballing list of mods you need to do it "right". Injectors, fuel pump, fuel pressure regulator, ECU....

The SIMPLEST real fix is doing a hella big port on your turbo wastegate so the boost stays at stock pressure and your stock fuel and timing maps are still in the ballpark. Unfortunately, as noted above, this job is pretty annoying to complete on account of all the things you need to unbolt and the fabrication.