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Discussion Starter #1 (Edited)
I pulled the injectors on my truck, had them tested, and the guy says that they're junk. Ok, so I'm looking for rebuilt injectors. The injectors that I have are an odd bunch; I've got (7) short injectors with #0430211051 and (1) long injector (was back in cylinder #8) with #0430211058.

I've read on another thread in here that the 1982's had coarse thread injectors whereas other years had fine thread. (I think I have J-code heads, because there's no cavity for an EGR in the intake manifold and the intake manifold head gaskets have that middle hole closed with foil). The comment was that the coarse threads are "unmistakable" somewhere to the tune of 7-8 threads per inch, but it didnt seem definitive. Anyhow, I dont have a thread gage, so I used the old tape measure and counted threads; I've got 4-5 threads in 1/4" of threaded body (3/8" of threads overall), so I'm thinking I've got 16 threads per inch. I take it that these would be "fine" threaded injectors? (1"-8 would be Unified National Coarse, wherease 1"-12 would be Unified National Fine threads) Having never seen "coarse" or "fine" thread injectors side by side, I wouldnt know how to judge them without having some specs in front of me (which I dont).

If these are in fact fine thread injectors, then the question is what the heck are they doing on my '82 truck? And why would I have fine threads on injectors numbered with coarse thread injector numbers? Is there a way to identify which heads I have on this thing?

I'll attach a picture of the injectors...

DSC00265.JPG
 

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Looks to me like what you have there are coarse threaded 1982-1983 style injectors. 7-8 threads per inch would really be coarse. I don't know what thread that was in, but it doesn't sound right to me. It would look more like a corkscrew for opening a bottle of champagne than a fuel injector.
 

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There are no coarse thread short body injectors, and since 7 were short bodies then all 8 must be fine thread.
If you have coarse threads there would be no doubt, they are VERY coarse. I can tell just by the pic that they are indeed fine.
So it would appear that these are not the original heads or possibly engine, which in this case is probably a good thing.
 

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Those are fine thread injectors. Short injectors were used in van's to provide clearance for the dog house. What color is your engine? Probably not the original engine or heads. All 82 engines were red all others were black.
 

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Okay, now I see the pic. Before it was rather blurry (my computer never did finish loading it). You are right, those are fine threads. Somebody must have replaced the heads on your truck at some point.
 
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