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Changing injectors
Posted: Fri Apr 22, 2016 1:22 pm
by dzammit85
Hi,
I just bought a adaptronic ecu for my nb8b, I'm looking at putting a turbo in but right now am just gathering the parts for it when I can afford them, so what I was wanting to know is would changing the injectors to larger ones be a good idea before I get the Ecu tuned for my car as it is now (without turbo)
Currently it is pretty standard, just iridium spark plugs and mangacore leads have been put in, and also a heavy duty clutch, lightweight flywheel and 3.9 torsen diff
Any thoughts on this would be great, even other things that I could change before tuning it
Thanks
Re: Changing injectors
Posted: Fri Apr 22, 2016 1:24 pm
by dzammit85
Also if you think the injectors are worth it, what ones would you recommend, as I have heard good things about people using the rx8 injectors in a mx5
Re: Changing injectors
Posted: Fri Apr 22, 2016 1:41 pm
by NitroDann
rx8 yellows. Do them now instead of tuning it twice.
Re: Changing injectors
Posted: Fri Apr 22, 2016 4:11 pm
by dzammit85
Ok great thank you
Re: Changing injectors
Posted: Fri Apr 22, 2016 9:47 pm
by 1green5
NitroDann wrote:rx8 yellows. Do them now instead of tuning it twice.
What?
Install injectors now = computer tune
install turbo & parts later = computer tune
That's twice
Install injectors at the same time as turbo & parts = tune once
OP, check out miataturbo.net
Re: Changing injectors
Posted: Fri Apr 22, 2016 10:29 pm
by NitroDann
When adding a turbocharger to a car already equipped with an ecu and injector upgrade you dont do a full tune.
The ecu upgrade will need:
Ecu install including running the hoses.
Wideband install
Basemapping including sensor and fuel system setup
Check base timing
Set limits and safety features
Tune hot start
Tune closed loop idle Idle
Tune Enrichment tables
Tune Coolant enrichment tables
Tune Air Intake Temp compensation tables
Tune 2/3rds of the timing table
Tune 2/3rds of the fuel table
Road test
If you install the ecu AND the injectors at the same time you need to do all of the above plus:
Install the injectors
This should be worth 10-15hp over not installing the ecu, however the injectors do not add power.
If he then turbocharges the car it will need the following ecu related work:
Tune last 1/3rd of fuel map
Tune last 1/3rd of timing map
Tune boost tables.
As you can clearly see this is NOT 2 whole tunes. Its one full turbocharger tune in 2 separate sessions. If you did the n/a tune, then swapped the injectors you would have to redo the following after the injector change:
Tune hot start
Tune closed loop idle Idle
Tune Enrichment tables
Tune Coolant enrichment tables
Tune Air Intake Temp compensation tables
Tune 2/3rds of the timing table
Tune 2/3rds of the fuel table
Road test
The above list is what most shops would call a 'full tune' which takes a week to get right, because cold behaviour is difficult to get right and needs a few goes when the car is dead cold.
Dann
Re: Changing injectors
Posted: Sun Apr 24, 2016 8:49 am
by project.r.racing
Dont argue with dann when it comes to injectors and turbos.

Re: Changing injectors
Posted: Thu Apr 28, 2016 9:32 pm
by IanR
NitroDann wrote:When adding a turbocharger to a car already equipped with an ecu and injector upgrade you dont do a full tune.
The ecu upgrade will need:
Ecu install including running the hoses.
Wideband install
Basemapping including sensor and fuel system setup
Check base timing
Set limits and safety features
Tune hot start
Tune closed loop idle Idle
Tune Enrichment tables
Tune Coolant enrichment tables
Tune Air Intake Temp compensation tables
Tune 2/3rds of the timing table
Tune 2/3rds of the fuel table
Road test
If you install the ecu AND the injectors at the same time you need to do all of the above plus:
Install the injectors
This should be worth 10-15hp over not installing the ecu, however the injectors do not add power.
If he then turbocharges the car it will need the following ecu related work:
Tune last 1/3rd of fuel map
Tune last 1/3rd of timing map
Tune boost tables.
As you can clearly see this is NOT 2 whole tunes. Its one full turbocharger tune in 2 separate sessions. If you did the n/a tune, then swapped the injectors you would have to redo the following after the injector change:
Tune hot start
Tune closed loop idle Idle
Tune Enrichment tables
Tune Coolant enrichment tables
Tune Air Intake Temp compensation tables
Tune 2/3rds of the timing table
Tune 2/3rds of the fuel table
Road test
The above list is what most shops would call a 'full tune' which takes a week to get right, because cold behaviour is difficult to get right and needs a few goes when the car is dead cold.
Dann
...and then takes as small breath, types another 2500words...
Re: Changing injectors
Posted: Thu Apr 28, 2016 9:37 pm
by bruce
And you get charged twice.
Re: Changing injectors
Posted: Thu Apr 28, 2016 9:43 pm
by Aiming Faster
Good juice there Dan, is that similar for ITB tunes (mine's a Megasquirt) too? Thanks.
Re: Changing injectors
Posted: Thu Apr 28, 2016 11:24 pm
by NitroDann
ITB's like an injector change require almost all of the tables to be retuned.
If you did ecu/tune.
Then you did injectors,
Then you did ITB,
You would do 3/4 of a tune 3 separate times.
Turbochargers dont affect idle or cold start of cruise in any meaningful way so adding a turbo is an easy tune most times.