injector size question
 

i bought my motor used with a pcm already tuned for the motor. iv been told it had 42# injectors on it but when i view the tables, it says 43.9#. how big of a difference will this make? are advertized sizes actually a little off? should i find someone that can flow these for me and get an accurate number?

when i got it, the motor had an adjustable fpr on it. i immediately took it off and put a stock one on.

Justin,

Are they SVO injectors? If so SVO's are rated at a lower PSI from ford (36 - 2 bar) and have to be adjusted to our higher PSI (43.5 - 3 bar) in the tables to keep you from being too rich. BTW - U coming out to C&C finally? Call me.

id love to come out to c&c but im always working when it goes on. i work saturdays.

iv had svo 36# on my old motor and these look nothing like those. idk what they are. they look like a factory injector so im guessin they are delphi

Pull the number off the side and post it up or google it as you should be able to find out real quick. I have FAST 42's on mine now and they look exactly like factory Delphi's (Bosch 3 design - but have a diff. model # on the side). The injector constant was probably tweaked a bit by your tuner as some go the lazy route and change the flow rate to lean out or richen the motor without messing with the MAF or Indv Cyld trims.

i wonder if i should leave it alone then till it hits a dyno.

ill get the number anyway

How do your BLM's look?

at idle, left bank is 125, right is 148. iv modded the bbk tb with the pipe between the tb and intake but it didnt make much difference. i think my o2s may be bad. im gonna try replacing them before i mess with fuel too much

Mine is the exact same, and it goes away once I give it any throttle. I've gone down every road and I'm pretty sure I'm going to have to live with the split BLM's at idle as it's pretty common with large cams. I'm at 230/236 with 108LSA. As to your inj constant, with those BLM's I wouldn't mess with it as you are going to have it Dyno tuned anyway and they will likely mess with them again.

i ran the number and it came back to a delphi 42.5# injector

43.9# is really specific tho.

Find out what PSI/Bar Delphi flow tests/rates them at as that could be the reasoning behind the higher injector constant.

the description on racetronix says 3 bar and that they are 42.29#

Ok, then who tuned your computer? They probably just did what I said earlier, and raised the injector constant slightly to bring the BLM's in check.

i was told golen did when they built the motor but i didnt know they did tuning

Probably, have a base tune they load for all their motors. Leave it be until you have the motor dyno tuned as your tuner is likely to change it anyway. BTW - Who are u having tune the beast?

i talked mike at gforce into it. i had to buy my own tuning software since they got rid of lt1edit. gotta get a few things fixed before its ready for the dyno tho. my head gaskets are leaking outside the block. not in the oil tho and the plugs look fine. while the heads are off, im gettin the intake ported. should make good power when its done

I officially hate you!!!! I tried for a long time to get anyone in Houston to dyno tune my LT1 and nobody wants to touch them these days. Finally ended up having Chuck do it (I KNOW) and he didn't do that bad of a job. I'm having Solomon help me now remotely fine tune it as I've got some grouding issues. Let me know how it turns out. You heard about the good power Neil put down right?

yea chuck tuned my old motor. didnt do too bad with it either.

neil was at the shop last week. i dont remember him talking about it but i think it was around 420ish, right?

Yup, that's what he said, pretty damn good for a stock short block!!!

I wonder how much the EFI live conversion helped him net?

idk but im seriously thinking about gettin the 24x setup. dont wanna have ignition problems on nitrous