Thread: Going from 42.5* injectors to 80*......change my tables?

Adjusting offsets is not particularly required.. if you get it wrong you really throw things off... So I would be careful.

I still run stock offsets with my 110# injectors... its easier just to account for it otherwise.

Originally Posted by BillBoost37

Hmmmm running in high speed mode, I should be plugging my stock injectors straight across the board from what I read. Thanks matt...you rock dude. Are you sure your Canadian?

Apparently you need a rewire else fuel pressure will bleed off.

97 GTP's had flat tables, then 98-03 was sloped oddly because of supply issues it seems.

This might just affect your holy regalness haha.

Originally Posted by copgtp

Matt, I plan on doing a full tune on the car with the new setup, ill keep everyone up to date as I'm sure ill have questions with this fancy hpt thing. Lol

Sent from my DROID RAZR using Tapatalk 2

And we'll be here to disagree about it haha.

Originally Posted by matt5112

Apparently you need a rewire else fuel pressure will bleed off.

97 GTP's had flat tables, then 98-03 was sloped oddly because of supply issues it seems.

This might just affect your holy regalness haha.

Stock offsets only make sense if your fuel pressure doesn't change 1:1 with the MAP. Even then, theyre only valid for stock injectors.

Incorrect. Offsets are not related to anything but voltage and are an ADDITION to your calculated pulsewidth, which is completely dependent on what OSID you are running... as you said some have flat the others are not.. But its more related to what bin file you are running, as NA cars typically have flat IFR vs MAP tables, while others did not... Most all supercharged cars are going to have linear IFR vs MAP, My 97 has a sloped linear IFR/Map Table.

Offsets change based on fuel pressure across the injector.

In our case the net pressure should be equal across the injector at all times.

Originally Posted by matt5112

Offsets change based on fuel pressure across the injector.

In our case the net pressure should be equal across the injector at all times.

Uh? Not even close?

Injector offset is the amount of time for injectors to pass the transtional stage. Otherwords injector closed-to full open amount of time this takes. This is usually set up by a mfg. for a specific application at a general voltage & a specific fuel pressure. Then a pcm has a better understanding of true seqential fuel injection & getting fuel there in right time & quantity especialy at high rpm.

ifr vs map is that whatever you are referring to, and that is typically just known as the IFR table.. Not the offset table.

Offset is Voltage vs millisecond.

Right so you say I'm wrong, but then say the manufacturers test at specific pressure as well.

Make up your mind.

I know what the tables do.

The question is: do you?