after looking at some dyno charts of same engine with bigger bore it seems like the power curve follows exactly just higher all the way through because of bigger displacement


so for example if I took a bone stock itr
replaced stock block with a 2 liter block of same compression and replaced the injectors with whatever percentage of fuel will be needed for increased displacement.

can it be ran on stock itr ecu?

this is just a theory im interested if its been tried or done and worked or failed?

 

Or you could just up the fuel pressure.

 

the fuel pressure changes when you increase fuel pressure it wouldn't be a linear increase in fuel

 

What are you trying to say here?

When you increase fuel pressure it will increase both while the FPR is out of vacuum and in vacuum. This is a viable option rather than changing fuel injectors. You could try a set of 310cc injectors or maybe 360cc and see if it lands you where you need to be. The issue with that is a static amount of fuel would be applied to the whole map and may affect idle and cruising too much. Playing with fuel pressure is your best bet and has been done for decades on EFI cars as a source to support mods.

 

I mean the fuel pump has slightly different output curve at different fuel pressure
would increasing displacement like that require change in ignition timing also?
I was gonna say to use slightly bigger injectors and then adjust it with the fuel pressure.

I was asking tho if this has been done before and was it a success or fail if anyone knows.
It would be cool to have a 2 liter in my 2000 gsr and still be able to use obd2 port for emissions and scangauge etc

 

Yes it has been done before.... Yes, it will increase injector output. But it is not a very fine adjustment, such as ECU tuning is.

 

I'm not what the appeal is in 20th century band-aids when we have modern tuning solutions available for exceptionally reasonable prices.
The reason you don't see piggyback controllers, missing links and FMUs anymore is because they're inferior and dangerous.
You could easily pass emissions on a stock obd2 p75 ecu if you're worried about CARB standards.
If you have an S300, demon, or hulog you can check codes, find the reason for the code, and possibly fix the error, all without having to dick around with a scan tool.

 

only on cold start and closed loop basically. once warm the ecu can compensate and keeps the afr in the mid 14s.

ive been using an adjustable fpr to help out on my b20s running p75 ecus on and off for the last few years now. the only issue ive run into is not making it too rich at cold start/idle while having it rich enough at wot.


with the knock sensor in working order and a wideband to make sure its cherry, im sure you could get away with running that motor on a stock ecu. this is how i plan on passing inspection on my upcoming 1.9L itr this year. not to drive forever on it, just for inspection purposes

 

It is how things were done for many years. Nowadays there is no reason to do it except for the ones posted above.

 

to bring it back from hibernation I still cant find any solid info on few questions

when increasing displacement I saw maybe one or two dyno charts that show pretty much linear increase in torque throughout the rpm
im assuming that means linear increase in fuel demand which means I can calculate what size injectors would work perfect for it. true/false?

when I increase the fuel pressure it changes the output of the injectors throughout the rpm and have a different curve because of the fuel pump
so its better to find bigger injectors and keep the fuel pressure at stock? psi?

I know its a crazy and strange project but I pretty much want to build a 2 liter type r motor and run it off a stock ecu in my gsr. because it has all matching vin tags.on engine and everywhere. the car is bone stock now with boltons I jus got done putting black interior its gonna be my daily driver that I want to enjoy driving.

 

Lets just end this now. You'll need to adjust for timing.

Just compare a B16 to a GSR map in Crome free if you really need to visually see how things change. What you're suggesting is honestly worse than the VAFC hacks of yesteryear.

But yeah, like Vegas said, get a modern tuning solution.

VIN matching Honda? That's fine and dandy, but then any non-OE offered equipment should be a no-no, at least in my book. You've already de-virginized her. You may as well treat her right.

I'm sure the last thing you want in your VIN matcher is to blow the engine. There goes that...

You can modify the internals of the ECU while maintaining the stock appearance, and thus the original VIN/Model number.

</end>

 

Its obd2.
I had a major headache trying to do tailpipe test failed 6 times. I dont want to do that again

 

B16 and gsr is completely different engine.
Differend dome compression different qurnch area and runner angle plus dual runner manifold

Im talking about using type r ecu with type-r motor that is bored to 85mm which is otherwise a stock type-r
Im gonna have to probably change to b16 head or just get a complete itr block and rebuild it but it wont be matching vins anymore

 

Just swap the Ecu and any required sensors/injectors for the stock Ecu to be happy. And yes it will run. My stock P72 Ecu runs my GSR engine bored/stroked to 85/89mm, 13.5:1 compression and big cams. I even ran it once on E85 because I was hoping to avoid draining the tank. All I had to do was crank the FP to 100psi lol. The stock Ecu (and tuning in general) is very forgiving at low load/rpm. Of course it wont make peak power nor would it be safe to redline but it runs it OK.

 

ok I figured this
I can run my Neptune ecu and datalog it in open loop to see how much fuel it needs at each rpm and then add fuel to make good at wot since the closed loop will adjust up to a certain percentage anyway.

 

damn i didnt know you went direct injection lol

 

Fuel pumps were howling. Couldn't get the catalyst monitor to set tho. Must be an EGT thing. Needs gasoline.

 

I basically have what you are wanting to build and trust me, a stock, non-tuned ECU won't run it very well at all!

My car is a 84mm darton sleeved C5 block
RS Machine 84mm "ITR" pistons
98 Spec ITR "PR3" head with full crower valvetrain
Stock injectors
Fuel pressure at 55psi (high side of spec per manual)

It wont run correctly on base maps or stock ECU's! As mild a build as it seems it needs tuning! Don't do it half ***!

 

are you running it closed loop?
have you tried increasing fuel pressure in open loop at higher rpm?
using wideband?


my theory was that if I can get it to reasonable afr during open loop at high throttle the ecu can adjust up to 15-20% but I was gonna try different injectors at stock psi

but no need now I actually picked up a type-r motor instead.
and got a pm from one of the ht gods here explaining it in more detail

technically I could go crazy and burn another chip for the stock itr ecu but its expensive and not much info and not clear if the obd2 port will work once chipped or not

in theory it would be similar to people running b20 on LS ecu

 

Yes its in closed loop and I have cranked the fuel pressure way up several times and barely notice a change on the wideband. This thing has had me puzzled for awhile, it seems like a simple build and should be easy to tune but it hasn't been! I thought by turning the factory O2 sensor back on and running closed loop that it would be able to compensate for the leaner AFR but it doesn't at least not in my case.

 

you also gotta remember the fuel pump flows different at higher psi.

 

That doesn't add up. Idle and low load calibrations are VERY forgiving. High load is a different story.

 

My thoughts exactly Muck... its had me puzzled for awhile now! I'm honestly replacing the o2 sensor for my wideband this weekend cause I'm really thinking its whats giving me false numbers and that my tune really isn't that far off