Hey guys,
I was hoping someone out there can help me identify these injectors. I bought a 92 305 tbi and the previous owner must have upgraded the injectors from stock. I would like to replace them or have them serviced but nobody around here can seem to identify them. I even took them to a shop and I am not sure if they damaged them or not. The side inlet filters they used to replace dont even fit, they just fall out lol. But eitherway I cant seem to find out what these may have origonally came off of nor can I find a rebuild kit (replacement filters). The best I can make of the #'s off of them are 01B20(8?) for the blue one and 01B216B for the grey one. Any help please would be very appreciated!

 

They look to be some sort of aftermarket TBI injector. They sure are not the stock Rochester injectors, that's for sure.

If you engine is a stock 305 best bet is to just get some stock 305 55#/hr Rochester injectors. Even a pair of JY pulls will do fine. Bazillions of them out there.

RBob.

 

I thought of that also so I bought a pair from the local auto parts store and put them in. Sadly I lost TONS of performance..... Thats why I was hoping to put the same "upgraded" injectors in. Or even find a filter set to replace the filters etc....

 

Those are a 45lb/hr injector. You will not find the bottom filter. The side filters are the same as the stock TBI filter if installed properly they should stay put.

 

Would you happen to know The best place to find replacements for the injectors themselves or what cars they came with origonaly? I thought the stock injectors for a 5.0 were 45 lb/hr already? Oh and THANK YOU VERY MUCH!

 

Stock 5.0l L03 injectors are 55#/hr.

If the ones you have are 45 #/hr then either the engine is running very lean or the fuel pressure has been increased.

RBob.

 

Yes, stock is 45lb/hr no matter what anybody else states, lol. I have had over 60 pairs tested and 305 injectors ARE 45lb/hr. Most flow 500-550cc/min at 14.7psi.

I have a brand new matched set that flows at 559cc/min. At 14.7psi these are closer to 55lb/hr injectors, but most calculations states you take the lb/hr and multiply it by 10.5 to get cc/min. So, a 45lb/hr injector at 12psi should flow around 475cc/min. Mine are tested at 14.7psi (1 bar).

Here are a couple of pictures. They are 01B205B 45lb/hr injectors. Pictures are not the best quality as I had to use my cell phone. Sorry about that!

 

Here is another pic for you. The injectors come with a basic installation kit which includes the two fuel meter cover gaskets, upper and lower injector o-rings, metal washers and side filters.

I do have matched sets of 55lb injectors as well if you need something flowing more.

 

I respect others opinions, but after having 60 sets (~120) 305/5.0L injectors flow-tested I find that they are 45lb/hr because every single one flowed between 500-550cc/min which is 45lb/hr because i have them test at 14.7psi. These injectors tested at 12-13psi which is typical would have pressures closer to 475cc/min

5235206 55lb 5.7L injectors flow in the area of 620-700cc/min. Again, this is after having dozens tested at 14.7psi.

I realize the "lb/hr" debate on here gets heated at times, lol...

 

Rbob knows his stuff and I respect his knowledge. I am sure he is correct with the statement he made, but... LOL!!!!

So, my "values" are based on actual flow-testing and not theoretical "should be" rates. GM had no rhyme or reason with what they did with regards to their TBI injectors.

So, the most important thing that i try to get across to anyone interested in flow-matched injectors is figuring out what their projected horsepower is going to be. Then finding them the best set of injectors that flow at the pressure/rate they need to support the horsepower they are projecting.

I have seen too many put a set of 90lb injectors in and have no idea what they flow, thus have no idea what they are capable of. I have had 42 sets of 90lb injectors tested (5235231). Their flow-rates ranged from 880cc/min to 1020cc/min. Many of which were new 5235231. This shows the huge difference in flow-rates of GM TBI injectors. I have 17084327 (~65lb cop car) that have flowed more than 80lb, etc. It's a crazy life dealing with GM TBI setups

 

The other way to look at the injector flow rates, or what they are supposed to flow, is by the BPC parameter in the calibration. In the AXKW calibration ('92 FED, L03, f-body), the BPC is 134. Reversing the BPC equation that GM uses is for 54.4#/hr injectors.

If 45#/hr injectors were used the BPC would be set to 162.

RBob.

 

Another location that provides TBI injector information can be found here:

http://www.turbocity.com/default.php?cPath=16_27_30

Apparently they too flow match TBI injectors.

RBob.

 

Also need to rememebr that there needs to be enough injector to support the engine's HP. From '88 through '92 the L03 in the Camaro and Firebird is rated at 170 HP. This is at either 4000 RPM or 4400 RPM (varied over the years).

A 45#/hr injector is not going to be able to support that. Even less so at the typical 10 to 11 psi that the TBI units actually run at.

RBob.

 

Wow you guys rock thank you very much for the deep/detailed information. With the information provided im still a little confused then. Why did I lose performance when I changed from the "oddball" injectors pictured for a pair of stock flow matched pair if they are both the same 45 lb/hr injectors (per dctrumpet) and or lower 45 lb/hr vs stock 55 lb/hr (per rbob)?

 

well could be that your calibration in the prom was changed to support your oddball injectors' flow rate (this is the mentioned BPC value). dunno how you could check this though. have you already checked your fuel pressure? if the oddball inj's are rated at a higher flow they would need less fuel pressure to flow the same amount as the (possibly?) smaller 305 stock injs (typically around 10-12 psi to support a stock L03 @170hp).

 

Stock is 55# on EVERY 305 I have seen.....46s came on the 4.3, sorry... Green/White color code injectors flow 55 lb/hr. I find it impossible to believe that 45# would support the stock TBI Trucks/Vans that made 185 flywheel HP stock and needless to say there is NO way I would have made 181 RWHP from 46# injectors at 12 psi.