99BackNBlackZ28

iTrader: (5)

With HPTuners, am I going to have any major issues tuning for SVO 42# injectors? The car is getting a cam & dry kit put on it, but for the moment can I tune the injectors for mods in my sig? I know they flow @ almost 50# @ 58psi.

2001 Pewter WS6

iTrader: (43)

I am interested in what parameters need changed as well since my injectors are on the way. Since they flow about 75% more fuel, can we just multiple the stock injectors rate by 1.75%?

pkincy

iTrader: (1)

Yes, you can.....on the IFR table (at least that is the answer I have gotten from everyone on my move from 28.8 stock injectors to Racetronix Lucas 42s.) And tune with a wide band to tweak that initial scaling.

My question is on the Injector Offsets. I am now using stock 98 injector offset table. It looks close enough to the table on Carprogrammer to work on engine startup. But I am concerned that this seems to be an area of much controversy.

I have posted a new thread on this question in the tuning section.

Perry

PS enjoy the new injectors.

Snake Eater

In HPT you can use there conversion calculator and input the injector specs. I.E.- 42#@45psi. Then you input the fuel pressure you will be running them at and it tells you exactly how many #'s they will be running at. Then in the fuel section theres the table with the current injector size. Just look at the largest number shown which for me was 27.10 and subtract the size of the new injectors. Then take that number and add it to the entire table.

For example. Stock injectors were 27.10 at max. New injectors were 43.82@58psi. Using a calculator subtract the 2. That comes out to 16.72. So you add that number to the entire stock table. Then it will run like a champ, and you'll be able to support a nice big dry shot.

99BackNBlackZ28

iTrader: (5)

Thanks for the very informative post man!

sprayinss

iTrader: (2)

yeah it can be done,just be carefull

mike s.

iTrader: (2)

What fuel pressure are the svo 42 pounders rated at? Also, are there any differences in injector size on stock ls1 f-bodys, i.e., are all of them 28 lbs/hr?

Here is some useful info if you havent seen it already.
http://www.hptuners.com/forum/YaBB.p...num=1111806579

prostock_bigblock

iTrader: (11)

r u sure pal!!! I think that they dont flow 50 @58 psi , because those r stock injector no. of 4 bar of fuel pressure which is =58

prostock_bigblock

iTrader: (11)

correct me if i am wrong ...plzz

WS6FirebirdTA00

iTrader: (33)

most stock injectors are rated at 3 bar

i have a program you can use, its excel, it will calculate the IFR table out for you. get a fuel pressure gauge for the fuel rail and you can put in the exact pressures you see and get it really accurate. just have to see if they are like the racetronix ones and are disk style or whatever they told me. they are more responsive and flow fuel faster so you have to adjust on the pulse width of them

pkincy

iTrader: (1)

[QUOTE=mike s.]What fuel pressure are the svo 42 pounders rated at? Also, are there any differences in injector size on stock ls1 f-bodys, i.e., are all of them 28 lbs/hr?

The Ford SVO injectors are rated at 39 lbs. About 90% of 3 bar. So you will need to scale them accordingly.

I recall my Lucas are 48.8 at my fuel pressure (42 at 3 bar) so yours are gonna flow a bit more. My SVO 30#ers flow at 32 #s in my LT1s (3 bar pressure).

I was able to get my pretty close by the straight ratio of injector sizes. But I also added 10% to the injector constant. Getting that right is critical as the big injectors only open for a split second at idle and if you have the injector constant (delay) wrong you will not run well at all.

Perry

WS6FirebirdTA00

iTrader: (33)

can you explain this injector constant, i was having trouble tuning for my 38# racetronix ones and noone seems to know a good answer, i just found out it might have to do with the pulse width. can you elaborate any or help me? feel free to pm me if you have time and we can talk on there so we dont take up this thread, or we can post up here to help others (prob a good idea since i found no info on this for my search)

SStroked 410

how big of a shot?

I have 42lb injectors with ls1speed high flow rails that I'm gonna use for my 410 once its together and want to run a big dry shot. I might go with ls1edit though, still not sure