I know the injector is smaller in dia. but are the connectors the same, and what about the areas that attach to the fuel rail and intake? Are these any different?


[Modified by 88_vette, 11:03 AM 10/18/2003]

 

The LS1 cars had Bosch 2 injectors. The termination is the same as the old Bosch style that has been around forever. And they will just drop in place of whatever used the old Multec and the old style Bosch injector.

The 6.0L and 8.1L trucks uses a new style shorty injector known as a Multec 2, that injector uses a smaller DIN style connection and it is not demensionally or electically compatable with the earlier injectors. The 5.3l truck engine may also use this same Multec2 injector, I can't say for sure.

 

I've been researching this lately. And, yes, from what I've found I am going to do this as well when a deal comes around. Can someone here clear up the fuel pressure issue. They are rated at 26 lbs. I believe. But at what pressure?

 

The LS1 engines are running about 58 PSI, or what is more commonly known as a 400Kpa fuel rail pressure.

The actual GM spec is: 384-425 kPa (55-62 psi)

 

Well, in that case, it may not be worth getting them. They may have better internals, maybe worth upgrading for that? But at that pressure, the 22lb. injectors would probably flow more than 26lb.

 

I had a guy wanting to sell the ones from his LS1 camaro and I wasn't sure about the fitting. They are rated at like 28LBS but I didn't know about the 58PSI deal. He was selling them for $50. I would like to have the smalled dia. look. But I think I need more injector, and if I run these at a lower PSI so not to max out the fuel pump I wil not get the 28# rating, and thus be back where I'm at now @24# :confused: what to do what to do.

 

I have the 2002 Z06 injectors. They are 28.8 lbs @ 58.4 psi. You have to mod them to allow for the fuel rail retaining clips to fit. Our stockers have a grove all the way around the injector but the LS1/6 only have the grove cut on 2 sides. What you do is use a needle file to make the groove go all the way around. I did go with an aftermarket pump to run them at the 58.4 psi.

I beleive the LS1 injectors are 26 lbs. Only the 2002 Z06 came with the 28 lbs.


[Modified by ericcer, 12:42 PM 10/18/2003]

 

WOW this sounds like something I may have to hold off on. It seems to be a little more involved tha I thought, and am willing to get into right now. Maybe this summer once school is out, and I have more time to spend on it.

 

There are lots of options for larger injectors or just replacements if that is what you are looking for. The main reason that GM went to a 400Kpa fuel rail was for emisisions. Its all part of the new LEV (low emissions vehicles) and ULEV (Ultra low emissions vehicles)standards that they are working with. At 400Kpa they get better atomization and better spray cone angles.

If you are looking for larger injectors I would suggest using the Delphi/Lucas disc injectors which are available in 37 and 42lb/hr flow rates @ 43.5 PSI. Or if you are looking for replacements to your stock injectors then there are always the Ford Motorsports that are available in 19 24 and 30 lb injector sizes Delphi also has the same sizes available but I am not sure of availability at this time as it is a new product for them.

From the sounds of what you are looking for, Racetronix has 28lb Bosch 2 injectors that are flow tested and in matched sets for $25 each. His rating is for the 43.5 pressure rating. However his ads say that they are the LS1 injectors which is a little confusing because I know that from 97 and up all LS1 rail pressures was set to the 400Kpa setting. This is a good deal for a set of "take off" injectors. Take off meaning that they were removed from new crate engines. You can check them out at:
http://www.racetronix.com

These guys are reputable people I have done a lot of business with them in the past couple of years.


[Modified by tjwong, 11:15 AM 10/18/2003]

 

thanks for the input guys. I will be checking things out, but staying with my 24# SVOs for now. I'm going to a mini-ram so I really anm not worried about changing them later on.

 

After reading the posts on this, I took 2 each LT1 and LS1 injectors and put them on my flow bench.
The 2 LS1 injectors are on the left and the 2 LT-1's are on the right. They were flowed at the same time and pressure. As you can see, the LS1's outflowed the Lt1's by about 3 or 4 percent.
Also included is a pix of the two types side buy side. This shows LS1 top groove not completely around the injector.

Click on the links below:

http://www.witchhunter.com/LS1vsLT1a.JPG
http://www.witchhunter.com/LS1vsLT1b.JPG
http://www.witchhunter.com/LS1vsLT1c.JPG

Hope this helps,

Gordon

 

Gordon, theoretically a 28lb LS1 injector rated at 400Kpa would flow just over 24lbs at 300Kpa. Making it pretty much equal to a 24lb FMS injector at its rated pressure. But at 43.5 PSI or 300Kpa the FMS 24lb injector flows a tad over 25. If I am correct that the FMS rating is 39 PSI. I know its less than GMs rating but I can't remember how much exactly.

 

A few tidbits...

Racetronix stocks the 19lb and 24lb disc injectors.
Racetronix has reclaimed 28 and 24lb LS1 injectors available (28lb cleaned & flow-matched only, 24lb flowed and cleaned only)
The LS1 motors have three injector part numbers available.
The LS1 injector is a faster acting injector than the RP / LT1 injector.
The LS1 injector has a much better factory tolerance than the LT1 injector.
The LT1 injector has the typical 'Multec' electromagnetic quirk inherent to many RP injectors where the LS1 & disc injectors do not making them more ECM / PCM friendly.
The disc and LS1 injectors are far more resistant to moisture.
The LS1 and disc injectors will fit a LT1 / LT4 and the connectors are the same.


[Modified by Racetronix, 4:42 AM 10/19/2003]

 

:hurray: thanks for the info guys. The flow thing that's cool. I guess I will have to go with the LS1 injectors then. Now I just need to find time to do all this.

 

Do any of these part numbers have the top holder groove all the way around?
Or, is it even necessary? If they are an exact fit, the retainer rings may not be required.

 

Most people do not use the clips as the fuel rail is enough to hold the injectors in place. If you insist on using the clips you can always take a small saw blade and make some matching slots in the side of the injector.