02-08-2006, 08:12 PM
What is the difference between matched injectors and not matched?
02-08-2006, 09:08 PM
Best case: nothing.
Worst case (new): about 5% natural tolerance is
what I've been told, though this was supposedly
the whole manufacturing distribution and in one
box you'd probably do a lot better.
You're paying for certainty.
By way of reference, if you had all of the injectors
but one dead-on, and one 5% lean, at WOT you'd
have (say) 7 happy guys at 12.8:1 and one at
13.4:1 who'd be the first to ping, and the first is
If I were spending $5000 on a motor I wouldn't
think twice about spending the extra hundred or
so for flow matched; one less thing to worry
But I have mysterious as-picked stock GM ones
in there now and a set of even more mysterious
used 32#ers sitting aroung, waiting to go in.
It's like blackjack, and insurance. Feel lucky,
or feel cheap?
02-08-2006, 09:34 PM
I've been doing inj work for about 10 yrs, and I've seen some, especially large injs that can be 10-15% off, one to another. One amazing inj is the stocker 28PPH, Bosch used in the turbo BUICKS.. I see ALOT of them with 100K on them, that clean right up, have a great pattern, and flow within a ML of each other. OTOH, I just did 2 sets of 160PPH,[New!] that took all 16 to get 8 useable.. IMO, they were JUNK...
Suppliers that sell alot of injs, usually pick a cutoff point for flow matched sets. IE: Racetronix, and PTE, I think, sell matched sets once the size is 50PPH, or larger. The cost is minimal, as they flow alot of pieces, and match them that way, no cleaning or rebuild parts are required..
Bottom line: If you have a $50 head, buy a $50 helmet. If you have an expensive engine, buy good injectors... :drive: