Larger intercooler = running lean?

[n4bes]

FCD is a way of bypassing boost limit.

A lot of Jap cars are set to run at a set max boost, say 7 psi.  The FCD is effectively a resistor which you splice inline between the boost sensor and the ecu.  The ecu then thinks the car is only boostin 4 psi when you are actually boosting 7, and so you can run say 12 psi instead of 7 limit.  The big prob here though is that you will run 12 psi but only be injecting fuel for 7psi.  FCD like this is a big nono on Rex.

Cheers Simon,

That\'s the point I was making Jim, they all know alot about these cars.......lol.

[Crazy Eddie]

Well I think this is the other guy\'s point. You are already running a decat which will potentially cause you to be running lean in certain circumstances. Therefor to add your SMIC will further increase the chance of running lean and then the engine may go pop!
I have SMIC decat and induction and PFC and my PFC shows up to 90% injector duty. Therefore without fueling mods I can\'t get anymore out of her.
The mapping keeps everything within a safety margin and although we are not talking about injector duty at the moment it is also another thing to consider. ie get the PFC then fit everything else and get mapped all in one go :cool

[interloper393]

Eddie so is that your cars using 90% of it`s output? so you`ve only got 10% more use from it? lol kinda wondered how it worked ..

[Crazy Eddie]

Yes basically it means that the 10% remaining is like a safety margine.
ie, If on WOT for example the car needed 100% injector duty but due to a slightly blocked injector (they are 14 years old ) it couldn\'t provide enough the car would run lean and potentially go pop :Thumbs-up

[n4bes]

Yes basically it means that the 10% remaining is like a safety margine.
ie, If on WOT for example the car needed 100% injector duty but due to a slightly blocked injector (they are 14 years old ) it couldn\'t provide enough the car would run lean and potentially go pop :Thumbs-up

Coooool,

Mine is at 45% @ 0.6 bar on my single, loads left for more boost......lol.

[interloper393]

Rub it in lol... how much weight have you save from the modded bumper lol

[n4bes]

Raw nerve you hit then mate.........no need.................lol.

[Jim_rx7]

Well thanks for all the info people!

Hopefully will have a PFC soon!

[interloper393]

soz dude, ack well nice reason to go shopping like i say cn fix it if ya wanna pop it down

[Jim_rx7]

Well I think this is the other guy\'s point. You are already running a decat which will potentially cause you to be running lean in certain circumstances. Therefor to add your SMIC will further increase the chance of running lean and then the engine may go pop!
I have SMIC decat and induction and PFC and my PFC shows up to 90% injector duty. Therefore without fueling mods I can\'t get anymore out of her.
The mapping keeps everything within a safety margin and although we are not talking about injector duty at the moment it is also another thing to consider. ie get the PFC then fit everything else and get mapped all in one go :cool

What you getting out of her at the moment mate? (bhp)

[Crazy Eddie]

Here is dyno was originally aiming for the elusive 300bhp but well happy with drivability.

[Jim_rx7]

I know this is off topic now (but hey, it was my thread anyway! lol)

How would you get more out of it?

Would fitting a walbro pump enable you to squeeze more out of it, or would you need larger injectors also? Or a FPR?

[Crazy Eddie]

Well I would go for better pump and additional injectors if I was to get more. The list of course can grow and grow.
I\'m happy with drivability and Pip has given me a safe map so will leave for now.

[m4drx]

i am running without cat and will be putting my big smic on soon.

basically in my opinion i can see there are too sensors to detect air mass and flow etc. the important one being the map sensor which takes a reading off the back of the plenum.

if it is a cold day this will fuel in a certain way and in the warm it will compensate.

if i put the big smic on all i am doing is slightly lowering boost and making the boosted air cooler as if a cooler day. if this is within the ecus limits and map then it should be fine, perhaps if i was boosting in minus temperatures with a huge ic then it could but i cant see how. the ecu detecs the air temp in the plenum so after the ic.

as for decat if you have boost spiking just get a boost controller - i have the greddy e-01 and i set my max vaue and now it will not boost any higher thus meaning no overboosting and no running lean.

this is my opinion so you can obviously make your mind up and i would reccomend the apexi but i think it comes over reccomended sometimes.

[Jim_rx7]

m4drx, are you running stock ECU?

I think the same way as you mate. It makes sense in my head anyway. lol

Just not sure about these rotary engines.

I\'ve never heard of a car needing a map/re-map after fitting a different IC. Obviously to get the best out of it, the car would require a remap, but not essential.

As for boost spiking, I\'ve still to fix a boost leak so it\'s not boosting 100% anyway, lol. So no chance of running lean... well not at the moment.