I want to keep a stock gsr engine and ecu so i can have my obd port functional


So for example if i do the following
Port the head and intake manifold stock gsr dual runner
Have a dc header and full exhaust with cat, short ram

switch to itr crank and pistons stock bore.


How much change can a stock ecu handle safely?

 

why would you swap out a gsr crank for an itr crank?

Stock ecu does not change anything in open loop, so you're definitely running a risk.

 

obd2 ecu's can handle minor alterations like you have listed pretty well, as long as you make sure there are never any trouble codes, especially regarding the knock sensor.
the things you have listed will not affect airflow enough in variance to require a special tune, at least theoretically. I would strongly advise getting a wideband installed though so you can monitor afr at all times. if you ever see it go too lean under load, you might want to consider a piggyback management system in order to keep it obd2.
that said, vtec controllers are garbage. the only piggyback systems I recommend are the emanage and emanage ultimate, preferably the ultimate.

 

yeah they do; fuel is altered according to fuel trims, and ignition trims are also set according to knock sensor feedback, as well as additional ignition retard at every instant any knock occurs.

for it to do so properly though relies on the difference in airflow from the mods being of similar characteristics between low load and high load.

 

They're generally rich from the factory, but you'll probably be beyond the comfort zone with those mods. In that case you'll be adjusting fuel pressure for extra fuel and the distributor position for timing. That's never a recommended tuning strategy. Keeping in mind that the ECU will only adjust during closed loop and closed loop does not cover WOT.

 

Crank is toast from rod knock and i have itr internals already from my other motor.

Its a 2000 gsr with everything original and clean im planning to rebuild the original engine
It will be my daily driver and i wanted to have a obd2 port for emissions testing and for adding somethimg like scangauge i will be taking it on long trips.

Not looking for crazy power just want to get few things upgraded while im rebuilding it


Should i just replicate itr engine then and find a p73 ecu?
That would probably be easier it already has p73 style manifold and header.

 

Wasnt there someone that could burn a chip for obd2 ecu?
I saw it on pgmfi obd2 section they did a p73 ecu and had some sucess with it

 

Some guys were replacing the processor with another reprogrammed processor. The processors were already discontinued at that time so it's doubtful you'll find one nowadays.

Someone else made a daughter board of some sort, but I don't know if that actually ever worked.

 

so if i duplicate c5 engine will i be able to use p73 ecu or gsr head will affect flow alot?

if i put itr internals :crank pistons valves springs itr cams and single runner first gen skunk2 intake manifold with 62mm throttle body

 

why is obd2 from those years the only non programmable ecu?

found the answer finally lol

just realized that i will have to deal with immobilizer now. its an obd2b

i couldnt find if an acura dealership could reprogram the ecu for my keys or cut me new keys to work with a new ecu...

 

The processor needs to be replaced, is why.

There's an immo disable board available for those ECUs. Xenocron and some others carry it.

 

nice. its a mission impossibru to find a 00-01 p73 ecu seems like

 

so should i be ok with the above setup and a stock p73-a04 ecu( obd2b) or should i not waste time on that?

itr internals in gsr motor with single runner itr style intake manifold

 

what about just replacing a gsr crank with ITR with everything else stock.

will that be ok with stock gsr ecu?


i have itr crank and its been impossible to find a undamaged gsr crank( been looking for over a week) they either beat up or overpriced.

 

You have to pay to play. How much is too much? I have at least 5 laying around...

 

im not trying to play im just trying to get this car on the road. theres none in my area.

the itr crnak i have i paid 180 shipped from member on HT.
not looking to pay more than that.
its for a different engine so i rather find a gsr crank for this one

 

Pay to play is just a saying meaning you want a good car? Ya gotta pay for it.

An itr crank is the same stroke as a gsr so no issue there.

I dont think the engine will be radically changed enough to not run ok on that ecu, but im not 100% on it. Its not like youre over boring it and running a radical cam profile.

 

You'll lose IAB functionality with the P73... Only thing i'd be concerned about is the added airflow potential form porting the head and IM. Probably would be a good idea to hook up a WBO2 for a few days to verify proper fuel mixture at WOT. Closed loop will take care of the rest.

 

i just dont know enough about the engine dynamics so i wasnt sure if having a heavier counterballanced itr crank will affect anything in open loop at higher rpm.

But it should be ok i guess.

I already got obd2b gsr ecu and stock dual runner intake im putting it back to stock everything
Its an original 2000 db8 gsr with all vins matching. Hard to find

 

If somethinG i could adjust fuel pressure to get it right in open loop and have the closed loop adjust for changes.wasnt stock fuel adjustment limit like 14%or 24%

 

OBD2 closed loop fuel trims should be able to adjust +/- 50% (25% short term, 25% long term). You will start setting lean/rich codes around 15% depending on load range. You'll need an OBD2 scanner capable of reading generic OBD2 live-data to view your fuel trims.

The adjustable FPR is probably your best bet for combating your fuel requirements at WOT(from the ported head & IM). I wouldn't worry much about lighter counterweights on the Type-R crank. Shouldnt cause any change in fueling requirements.