LS1 Stock Injector Sizes By Year

1998 28.6 lb/hr
1999-2000 26.4 lb/hr
2001-2002 28.8 lb/hr


I currently have stock injectors in my '99SS. Should I upgrade considering the mods I have ,and to what the 28.8# or SVO 30#? What would you recommend and why?

Thanks,

 

I don't really see why you would need new injectors unless you're bringing more air into the car. I didnt replace mine until I got my Pro Charger and before that I was pushing 360 at the wheels and was fine with the stock injectors.

 

blown346, Thanks for the reply. Do you have a '99?

Thx.

 

I have a 2000 SS.

 

TTT

I'm curious about this too and would like more opinions...

I've gotta 2000 (so same injectors as HOSS99 )

Stick with 26.4 or upgrade to 30# injectors ?

 

Just monitor the injector pulse widths vs rpm, and then calculate the injector duty cycle. If you're over 80%, you could use an upgrade.

I have a 2000 T/A with mostly breathing mods: lid, LS6 intake, FTRA, headers, catback etc., and I needed to upgrade the stock 26.4 lbers. Plus it's a lot easier to tune by pulling fuel rather than adding it.

 

Just monitor the injector pulse widths vs rpm, and then calculate the injector duty cycle. If you're over 80%, you could use an upgrade.

I have a 2000 T/A with mostly breathing mods: lid, LS6 intake, FTRA, headers, catback etc., and I needed to upgrade the stock 26.4 lbers. Plus it's a lot easier to tune by pulling fuel rather than adding it.

 

Ford SVO 30#ers, $219.00, Summit Racing.

 

Cool, thanks.

I'm doing Heads/cam/headers/intake etc... next week, so I'll pick up some 30 lbers. Are the Ford ones ok to use? Or should I go with another brand?

 

The Ford SVO 30s are made by Borsch which is the same company that makes GM injectors. These injectors have been proven over and over in our cars.

All you need to do is adjust the Injector Flow Rate table until your LTFTs are slightly negative. Leave the Injector Offset table stock.

 

Sorry, "Bosch."

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Predator:
<strong> Just monitor the injector pulse widths vs rpm, and then calculate the injector duty cycle. If you're over 80%, you could use an upgrade.
</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Great advice here. I think a lot of 99-02's with H/C/I mods are probably at the 100-120% DCC range. Fuel injectors are not supposed to be run maxed out like that. 120% is dangerous in my opinion.

I ran some GM injectors that were OEM for a GTP, and they were rated at 39.5 lbs according to Harlan, at our fuel pressure. Lots of headroom for a heads/cam/intake car, I made 475rwhp/505rwtq with mine with the old 422ci.

 

Cool. Thanks for the info. I think you may have answered the question in my post. "redundant injector question" <img border="0" alt="[USA]" title="" src="graemlins/patriot.gif" />

 

Thanks for the info.

 

My injectors were fine when I was a cam only car. Not until I went with GTP S2 H/C did I have a problem (actually started going lean at 6500 rpm)

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Predator:
<strong> Just monitor the injector pulse widths vs rpm, and then calculate the injector duty cycle. If you're over 80%, you could use an upgrade.

</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Would someone be so kind as to detail how this is calcluated ? I can monitor pulse width and RPM with ATAP, but how do you calculate the duty cycle ?

Thanks !
Rob (Bad30th)

 

NM, found it. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

Here are some useful snippets, copied from previous posts :
--------

Use this formula:
lbs/hr=(BHP X BSFC)/(No of inj X DC)
BHP=Peak Horse Power
BSFC=Brake Specific Fuel Cosumption
DC=Duty Cycle
So, (650 X .50)/(8 X .85)=47.79lbs/hr. I've been told to use .50 for the BSFC of engines with power adders such as blowers/turbos/dry nitrous systems. No power adders use .45 BSFC. If you used a .55 BSFC you'd come up with 52.57lbs/hr. The .85 is for 85% injector duty cycle. Hope this helps.
...

hey rich, i don't think they are geting what you are saying. lets figure 15%driveline loss(guess), so your looking at no more than 600fwhp. now use that number in his formula. everything i have read says .50bsfc for a NA set up, sooo

(600 x .50)/(8 x .85)=44.11lb/hr

now lets look at those 42svo's, to figure the flow at 55psi you need to take the (square root of 55/43.5) x 42 = 47.22actual flow at 55psi.


Thanks !
Rob (Bad30th)

<small>[ April 16, 2003, 03:24 PM: Message edited by: Bad30th ]</small>

 

RPM vs PW table to help you calculate usage:

http://engine.firebirdv6.com/pulsewidth.html

 

"Forbidden."

<img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />