General Bigger injectors ok without tuning ?

[Dsmj89]

Couldn't find the answer to my question so i will ask here.
Next year i am looking forward to finish up my fuel system minus the tuning device, due to money issues i will have to save up a little extra and buy it on the side a couple months later.
My question is, if i were to not only install the 255 fuel pump and fpr but also a set of 650cc injectors, will it run like crap/rich even if i dial in my maf-t to read 650cc's ? Or will it be ok ? Thanks.

 

[LiquidX]

The fuel pump will be fine the the AFPR since you are restoring it back to stock pressure. If you can tune the MAF-T to the 650cc then you'll be fine. If you don't have any real tuning system then you'll run rich. Have fun tuning with the MAF-T though. It'll be a rough tune so you'll still run a little rich but not as bad as without it.

 

[Dsmj89]

Yeah i just taped up the white rpm signal wire since i won't be using the maf-t to tune, just wanted to know if it won't be horrible as compared to stock mas vs the gm maf already dialed in for the 650's.
Can't wait to get link and sell the maf-t.
Thanks liquid.

 

[the_mork]

If you choose to tune with an MAFt then I suggest using it in drawthrough. If you run it that way you should probably be okay with relatively minimal annoyances.

 

[LiquidX]

If you want to get link, why don't you just hold off on the injectors and sell the MAFT now and save up for link. But if your MAF is already programed for the 650s you'll be fine as I said.

 

[1gDSM4g63]

It can be done with a MAF-T, but I don't see in reason why you'd go to the 650cc injectors. It's a real nightmare stopping and going to adjust the tune and worst of all you'll need a wideband too. It's just my 2 cent that you'll cause damage and have none or minimal gain.

 

[Dsmj89]

If you choose to tune with an MAFt then I suggest using it in drawthrough. If you run it that way you should probably be okay with relatively minimal annoyances.

Not planning to tune with the maf-t, it's just a temp unit to run my car with it until i get link. I never had intentions of using it to tune with.

If you want to get link, why don't you just hold off on the injectors and sell the MAFT now and save up for link. But if your MAF is already programed for the 650s you'll be fine as I said.

Thanks for the input.

It can be done with a MAF-T, but I don't see in reason why you'd go to the 650cc injectors. It's a real nightmare stopping and going to adjust the tune and worst of all you'll need a wideband.

Yeah i hear you man, no worries i was asking this question as i want to upgrade my fuel system to get it out the way next year and run my 650's without running like crap while i save for link.

 

[jeffo]

The biggest problem with the MAFT and 650cc injectors is that you are going to be removing ~30% of the airflow signal, so the ECU is going to be using the wrong maps. Fortunately, the 2G maps are very conservative, and can use more timing advance, especially if you are running 93 octane. Without having any way to log knock, or a wideband to see the AFR, just be careful and keep the boost down until you buy the DSMLink.