680cc injector limit?

[ebb3ka94]

So i have a spun bearing on my 4g63. Was wondering what i would need to do if i was going to swap in a used short block with 9:1 pistons. Right now i have a stock longblock with 680cc injectors and 3g lifters. Cars dyno'd 330whp @ 22psi w/ a 6bolt 4g63 and 16g. Was wondering how much of a hassle it would be to swap the new shortblock in if it had higher compression pistons. Around here we have 93 octane as the highest, unless i want to go to the one gas station in town with 110

Thanks in advance

 

[pauleyman]

Are you talking about a stock NT shortblock? If that's the case it isn't just compression that's different. Physically they are the same but it isn't an apples to apples comparison.

 

[ebb3ka94]

Are you talking about a stock NT shortblock? If that's the case it isn't just compression that's different. Physically they are the same but it isn't an apples to apples comparison.

No its a built turbo short block with 9:1 compression pistons in it. I was wonder if my 680cc injector will keep up, when boosting to 18-22psi. I have a wideband and tuning software aswell.

 

[nocardick]

I'm at about 21psi with mine and they are at their limit

 

[untouchablecc]

Hmm interesting. I have been hitting between 25-30 psi on my hx35 8 blade without knock. I need too look at my AFR and inj duty cycle

 

[ebb3ka94]

You 2 are running 680cc injectors though? I just need to know if I'm going to run into problems with 680cc injectors with higher compression pistons.

bump

 

[phillytalon]

its always easier to go larger injectors and not have its duty cycle at its limits, if your build changes your already set up