Best Course of action?
 

Hey guys,

In the coming weeks I'm buying my brother's old FD and i was wondering what bits of advice you had for upgrades/maintenace/mods. I was hoping for some advice on an upgrade for the stock twins (I'm in love with the 4500rpm transition and i dont want to make huge power, just reliable fun) It's got 43000 miles on it (68500 in canada).

here's whats been done so far

Everything else is factory and untouched, even the stock exhaust. It's a JDM car so there's no Pre-cat from what i understand.

Tell me what you'd recommend for better twins etc..., I'm likely going to go with an apexi PFC and a better exhaust but other than that I wasnt planning on touching it.


Thanks in advance, heres some pics

If you want to stick with a sequential setup, you have 3 basic upgrade options:

1) keep the current twins and tune for power. Mine is making about 320 hp with a street port, APEX'i PFC + Commander, Apex'i intake, Ẽfini Y-Pipe, Mazdaspeed Radiator, Pettit Racing intercooler & downpipe, HKS exhaust, Magnecor spark plug wires (the previous owner installed all the mods – he was a time attack champion and race instructor)

2) 99 spec turbos: 99 Spec Efini Twin Turbos

3) BNR stage 3 turbos: BNR Stage 3 Turbo upgrade

Either turbo upgrade can take you up to about 400 hp or more, but they need to be tuned properly and supported with the right mods (e.g., fuel pump, intercooler, ignition, etc.). Obviously, you don't want to blow anything up.

You don't have to buy the stuff from BNR, but they have informative descriptions.

I had a 92 FD with BNR turbos that made 350WHP and very much enjoyed the power delivery. Im not sure if it was because of my tune or because of my hardware setup but god dam when the first turbo kicked it pulled hard and dear god when the second one came online you had to be prepared for it to not crash. The dyno chart had split in two "humps" the first hump being the first turbo coming online and at around 4500-5000 rpm the power would quite literally drop, immediately after the power started dropping the second turbo would come online very suddenly. I truly believe this was because of my super long piping I did for the intercooler and the cold air intake, so you might not have this problem. Anyway I cant speak about reliability or how far you can push the turbos but if you love the 4500 rpm hesitation and think 350whp is what you are looking for the BNR turbos are the way to go. Oh and since you like the 4500rpm hesitation the BNR turbos seemed to exaggerate that. Now please note this, the car was unfortunately crashed by a novice driver who I trusted with the car, the hesitation is what caused him to spinout mid corner so be careful with the hesitation it can take you by surprise if you are not used to it.

Thanks for the info, I learned my lesson about the second turbo around corners, i have a feather-foot technique around sharp bends that keep the RPM climbing slightly but the second turbo stays off, after the bend i can go full throttle again and it comes on instantly

IMO:
• Remove Turbo Timer it just another failure point. Besides it is worthless, just cruise the last five minutes of your destination
• Get a boost gauge – make sure you test it out first to make sure it is accurate
• Get a boost controller – Note if you opt for an electronic version there isn’t a need for a boost gauge as the controller will display your boost level.
• Install RB duals – quiet non droning, very pleasant exhaust actually with a stockish look to it
• Upgrade the stock IC to a Vmount style. My recommendation: Go for the greddy as it retains the AC.
• Don’t get a battery that is too small for our cars
• Get an resonated MP and at the same time get an ECU
• Obtain ECU & elevate the boost to 12 psi (of course tune for it).

^^ With those mods your car should be very reliable and be decently fast. Note that once you up the boost past 12 psi you will be subject to more complexities. Additionally, you will decrease the longevity of the stock twins and it will require that you upgrade the fuel pump and injectors. To be honest once you have start messing with the injectors/fuel delivery things get trickier. So for a rock solid fun car that doesn’t flood and starts every time, stay with the stock fuel system.

For the future:
• Once your stock turbos become tired; don’t buy used or have them rebuilt. Just buy new or upgrade to BNRs
• Delete the AST (No reason to have an AST if the system is burped correctly. Deleting it removes one more possible failure point)
• Replace Apexi intakes with a real CAI such an M2 style box

^^This. Except I would add that there are decent SMICs out there if you can't afford V mount right now. And for best reliability add a boost activated WI system. Inexpensive, reliable and better cooling with carbon and knock control. It can be also be almost invisible under the hood.

Echoing the montego guy with a yellow car ;) and Sgt

• Remove Turbo Timer it is useless. +1 The engine bay will get hot sitting there idling w/o airflow associated with driving the car.
• Get a boost gauge – make sure you test it out first to make sure it is accurate

• Get a boost controller – I'd personally hold off on this until you determine how well the existing stock system is regulating boost. If it isn't doing a good job, then go ahead and get a decent electronic boost controller. Doesn't need to be anything super fancy.

• Install RB duals – This is personal preference. If you are OK with the existing sound and noise levels, leave the stock system alone.

• Upgrade the stock IC - A good SMIC is totally fine option and will help the car run better and safer by decreasing Intake Air Temps.

• Don’t get a battery that is too small for our cars

Additionally, I would never get a mid pipe w/o a cat. The exhaust smells too damn much and you introduce the risk of potentially engine failure if you don't have good tuning and excellent boost control. Good tuning is really hard to come by.

The one reliability mod that I don't see on your list is replacing the stock cooling hoses. Do it if it hasn't been done already. When replacing the stock cooling system hoses, get all new OEM spring type hose clamps. Get rid of any worm gear hose clamps. They suck. I've posted on that topic before if you want to search.

Read the FAQ thread!!!!!