scott87star Posted December 1, 2014 Report Share Posted December 1, 2014 (edited) So someone asked me a few weeks back which injector was the primary and which is the secondary, black or green (blue, whatever) and my reply was "I don't know, I don't pay attention because I always flow them". I'm working on a twin secondary injector TBI build at the moment and had two sets of black and green injectors, one set from the 87 flatty project car and one from a member on here whom shall remain un-named. The latter set were billed as being almost new 87-89 set with very few miles and they look it as the bodies are spotless and the plastic very clean and bright. Sadly they were both plugged almost solid, after working several solutions through them I finally got them working well again. I build an injector test rig because a lot of aftermarket injectors don't come with data, the kind of data important to a good running car using an aftermarket ECU like megasquirt, dead time, actual flow at various pulse widths and voltages and actual flow at very low pulse widths. Of course I got a big surprise part way through, I had a black top on the test rig and it was flowing every bit as much as the green top I'd just done. I finished testing all four before I entered all the data into a spreadsheet to get the actual flow rates: black #1 550 cc/min, black #2 932 cc/min, green #1 929 cc/min and green #2 1117 cc/min. Thanks to member Indiana who posted the answer to the puzzle, it was an H serial number injector from 84-85 that is interchangeable with the 86 injectors. http://www.starquest...showtopic=90896 Even stranger, the other injector was a J serial number 86 injector with a green top, I haven't dealt with many 86's but I thought they flowed less and were all black top. My 85.5 has two black tops in it. The injectors from the flatty were correct L and M code injectors. Moral of long winded story, get your injectors flowed! If you're running an MPI it's even more important as there is quite a bit of variation injector to injector. Edited December 1, 2014 by scott87star Link to comment Share on other sites More sharing options...
IntercooledFlatty Posted December 1, 2014 Report Share Posted December 1, 2014 what power supply do you use ? i've read a 9v battery works Link to comment Share on other sites More sharing options...
scott87star Posted December 1, 2014 Author Report Share Posted December 1, 2014 You can use a 9 volt battery to open/close but you wouldn't get any good flow data. I use a variable DC power supply. Link to comment Share on other sites More sharing options...
IntercooledFlatty Posted December 2, 2014 Report Share Posted December 2, 2014 Now I think about it, the 9 volt was to open em up to clean em Link to comment Share on other sites More sharing options...
ucw458 Posted December 2, 2014 Report Share Posted December 2, 2014 An even better option would be to not cheap out on injectors. Instead of getting bargain basement injectors go with a reputable company like fuel injector clinic. You pay a little more but you get quality injectors that are a flow matched set with all the data needed for your standalone. On that note, never buy smartfire injectors on ebay. They are a chinese copy of a bosch design. They are horrible injectors. Link to comment Share on other sites More sharing options...
markhansenconquest Posted December 2, 2014 Report Share Posted December 2, 2014 U CAN MEASURE THE HOLE TO SEE IF ITS 850CC OR THE 550CC....I CAN SEE THE DIFFRENT HOLE SIZES BY EYE..... Link to comment Share on other sites More sharing options...
ucw458 Posted December 2, 2014 Report Share Posted December 2, 2014 U CAN MEASURE THE HOLE TO SEE IF ITS 850CC OR THE 550CC....I CAN SEE THE DIFFRENT HOLE SIZES BY EYE..... Hey Mr all caps, you can't measure flow by looking at it. Just because it's supposed to flow 550cc doesn't mean it actually flows 550cc. That was the lesson Scott was trying to convey. You should read his post again. Link to comment Share on other sites More sharing options...
psu_Crash Posted December 2, 2014 Report Share Posted December 2, 2014 Scott so are you saying you can flow/clean injectors now? Link to comment Share on other sites More sharing options...
scott87star Posted December 2, 2014 Author Report Share Posted December 2, 2014 I can, but I can't do it as inexpensively as witchhunter, $22 apiece. That being said they don't supply the low PW flow rate information that helps big injectors work well at idle, so if you're after that then hit me up. Link to comment Share on other sites More sharing options...
scott87star Posted December 2, 2014 Author Report Share Posted December 2, 2014 http://picturehosting.com/images/oblique9881/greenblack.jpg So when I pop my hood at the next meet how long do you think it'll take before someone tells me I have my primary and secondary backwards? Haha, they both flow 930 cc/min. Link to comment Share on other sites More sharing options...
pcristquester Posted December 2, 2014 Report Share Posted December 2, 2014 http://picturehosting.com/images/oblique9881/greenblack.jpg So when I pop my hood at the next meet how long do you think it'll take before someone tells me I have my primary and secondary backwards? Haha, they both flow 930 cc/min.Good conversation piece at least Link to comment Share on other sites More sharing options...
IntercooledFlatty Posted December 2, 2014 Report Share Posted December 2, 2014 i see what you did there Link to comment Share on other sites More sharing options...
mopar jon Posted December 19, 2014 Report Share Posted December 19, 2014 A very helpful informative post, great job Link to comment Share on other sites More sharing options...
importwarrior Posted December 19, 2014 Report Share Posted December 19, 2014 hey your injectors are.... that looks nice all in black. Link to comment Share on other sites More sharing options...
Fuze Posted December 19, 2014 Report Share Posted December 19, 2014 Yet another Starion mystery! I thought all greens were secondaries from 87+. Link to comment Share on other sites More sharing options...
questsale Posted December 19, 2014 Report Share Posted December 19, 2014 while you can use a 9v to see if they work, or run some cleaning fluid threw them, that wont determine any leaks, give you a proper spray pattern, and wont do much of anything without proper pressure. Link to comment Share on other sites More sharing options...
twojayzeestarion Posted December 20, 2014 Report Share Posted December 20, 2014 I always put min in a spare tb fuel rail and price the ic pipe goes to the run a spare fuel pump in a loop to wherever you want to Link to comment Share on other sites More sharing options...
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