rotary.yannis

I've already talked to a few people and gotten different opinions.
I'm in the middle between the classic Power FC and a Haltech Elite 2500 with it's Plug n' Play adapter..
Does anyone here know anything about it and can tell me which one is better for easy handling and simple "tuning" (...flames...)?


For example the topic of a midpipe.. What are the most neccessary things to do before putting on a straightpipe?

j9fd3s

iTrader: (3)

Could you expand on what easy handling is?

Jesturr

The right answer is the one from the mouth of your tuner.

If you're removing restriction from the exhaust, you need to make sure the rest of your boost control is up to the task of handling the free-er flowing gas. Usually this means porting the wastegate. (in addition to ECU tuning)

ZumSpeedRX-7

iTrader: (12)

Without the token response of "search the forums" as this topic has been covered from the analog Power FC ages in our Big List days to the more recent digital ages...

Expanding on your FD build and what you need is required for an appropriate response here (like Mike said above)


I had a Power FC for many years on my twin turbo set up and switched it out for an Elite 2500 for my single turbo set up, but wouldn't definitively point you to one or the other without more context

rotary.yannis

For example as far as i know the PFC has the Commander for easy displaying infos of the engine.
But what does the Haltech have for displaying important infos about the engine?

rotary.yannis

A buddy of mine is driving straight piped with his PowerFC and StockTwins (without porting the wastegate...) and it ran fine for the last 20.000km...
Is there something else he might have done to it to have no problems without the restriction from the cat?

rotary.yannis

So are u trying to say u would recommend the PFC for the TT and the Haltech for ST?

j9fd3s

iTrader: (3)

the PFC is great for the stock turbos, because it just runs them right out of the box.
you can adjust the amount of boost, and how quick it responds really easily too, so its not too bad to make it ok for a mid pipe

if you do go with a PFC, look at the FC Tweak software, its really really good

ZumSpeedRX-7

iTrader: (12)

No, not necessarily. The Power FC is an awesome standalone, and although doesn't have the same capabilities as a modern ECU, it is relatively simple and works very well


Like also said above, more important than the ECU is finding a local tuner

boostin13b

These are essentially two different worlds of budgets. In order to control the sequential operation you need one of the higher end Haltechs like the 2500 or newer Nexus IIRC which will support all the modern safety features. If you are just looking to do basic mods then PowerFC has been the "Go-To" for decades for its reliability but lacks a lot of the modern safety features. It is proven for the twin setup and has tons of support still and now more than ever with the new tuning software creation and updated screens etc. Definitely do some searches on these because as others have said, this is a regular discussion but in the end it will depend on your budget (PowerFC is a fraction of the cost when you factor in all the extra sensors and such needed with a haltech type setup.) I will be in the same boat with my build eventually and will totally depend on my budget when I reach that point.

rotary.yannis

So would I be able to drive with a midpipe with the PFC only? (without porting the wastegate for example)

rotary.yannis

Since I'm not planning to go for a Semi PP with a Big Single Turbo ur saying i can easily go for the "cheaper" version which would be the PFC?
Im not intending to go for a ST but what I have in mind for the future is a bigger intercooler and maybe sometime in the next few years a half-BP...

But to be clear.. Am I able to drive with a midpipe with the PFC or is it neccessary to port the wastegate?

Jesturr

You're likely getting the same responses because the RX7 especially with twins isn't a car that can be changed so easily and driven around.

In stock form, the intake, exhaust, turbo system are balanced together for safe stock power. In an NA car, throwing an exhaust on a car wouldn't upset that balance as much. For these cars, just tossing in some change to airflow upstream or downstream will affect how the engine balances fuel and air, and can have very quick very catastrophic damage to the engine. It's not as simple as downpipe + PFC + midpipe = running.

The change to a catless downpipe and a catless midpipe with nothing else would force more air through your turbo.

You've got two paths here - you can accept that your turbo would be running more boost for the added airflow. You would need to add _some_ kind of aftermarket ECU and then tune your new ECU to deliver the fuel and the timing to safely run your new higher boost. Edit: This could also mean changes to your fuel injector or fuel pump if you car can't deliver safe fuel quantity for higher boost.* Whether you get a PFC or a Haltech depends entirely on what your tuner is comfortable tuning - even if a PFC is easier to use it's worthless if your tuner isn't comfortable with it. You really need to find a tuner and then ask them what they're comfortable tuning with, and that's what you should choose.

Regardless I've heard stock twins don't like much more boost than they're giving out stock - I've heard 12psi is the limit of "happy" that they run at.

Your second solution is to prevent the extra airflow by porting the wastegate in your turbos. This is a big job, but it lets your turbos bypass more air away from your turbine and control your boost a lot better. Like before, you'd need an aftermarket ECU so that your maps behave with the new way your engine is getting air delivered.

If you're trying to go for louder, you're looking to get necessary changes to your exhaust that you will have to tune for. The safest is to have the person tuning your car also installing these mods. I would not change parts that affect airflow and then drive my car without first getting a new tune.

If you're trying to shoot flames then you'd ask your tuner to raise the RPM threshold of fuel cut or turn fuel cut off entirely.
Ironically I've heard it's healthy for rotors because the fuel on decel cleans carbon. It's looked down upon here in CA because backfires have caused outrageous forest fires.

You're getting a lot of snarky or dismissive responses because each of these are items you can research yourself to run the car safely. The level of research you're doing on your own before asking questions is leading to the image that you're likely going to damage your car trying to get to the build you want. I don't want to be rude, everyone starts out new and learning. To be honest, though, you need to do some reading and research or you're going to end up with a car that's nothing but problems and a big heartache until you sell it.

Haltech and HP Academy have great videos for getting your feet wet into the technical details.

rotary.yannis

Okay wow. That’s a lot of info! Thank u so much for explaining it this good. I’ve already read a few topics about this midpipe thing with aftermarket ecu‘s but i never really found something like this.

You mentioned a point with shooting flames, which was my first intention why i wanted to know these things about midpipes.

The thing is, im pretty sure my cat is already non functioning anymore because before i rebuilt my engine, it ran on only one rotor (no.2 had no compression which means a lot of unburnt fuel got into the exhaust) and there were up to 2m wide flames.

Would it be possible to shoot flames again (with a good running engine this time) but still with the defect cat in for the restriction in the exhaust?