Does anybody have any current information for the latest and best replacement injectors for a 500EFI. Seems to be somewhat of an unknown subject. I know it has been discussed, but what are the real deal brands and part numbers. TIA Stealth

I find it really odd that no one on this board has any information on this subject, with all of the 500 and 525 motors still running around. Maybe it's a secret--dunno.

Bajaor Thanks for the lead, I will see what they have to say. Stealth

I flow and clean them as part of my business, unfortunately when you have "bad"ones , ie, high resistance, low or high flowing etc, if cleaning them doesnt straighten them out, there is no "fixing" them, i had quite a few spares i would substitute in sets to make "good" sets, i finally ran out and have no more extras. Fast forward to now, i recently flowed and cleaned 2 sets for a well respected engine builder on here, when i got half way thru the second set i found two bad ones. There is alot of info claiming these are 42 and 38 lbs. So i ordered one 42 lb and one 38 lb of a different sftermarket brand. Flowed them side by side some of the "good" ones, no comparison, the 42 lb flowed 27 to 30% MORE than the normal flowing stock ones, the 38 lb flowed 17 to 19% more than average flowing stock ones. So i HAVEN'T found a "drop" in match, when comparing aftermarket to stock ones, i don't know the solution. Im not wasting anymore time trying to find a direct crossover as if there WAS one they would be everywhere for sale. Instead im going to work on a tune on my dyno and in my 500 efi powered boat for aftermarket ones that are reasonably priced.

38 lb, 42 lb, stock left to right at 3000 rpms, 8.0 ms and 60 seconds

My machine is a mid level one, has quite a range and adjustability, it does not, however, have a static test for determining size of a unknown one, i can only go by previous test and data from others i have flowed.

artic I have followed a lot of your threads, knowing you have been looking for a replacement injector. Blows me away that Mother Merc. would use something that is that difficult to duplicate. Could be by design--so that replacements are a b--ch. Stealth

the 500 EFI injectors are not 32 lb injectors.

And if someone reports that they have a crossover straight out of the box they are bull chitting 1000 percent cause it does not exist. I even met with Bosch over the winter , brought them the 500 EFI injectors. They told me through their current data base NO GO --- do not have a plug and play match period.. Also they are not interested in coming up with a plug and play match either because ( Their WORDS ) not enough volume and its a marine engine with outdated technology. Actually they were very nice to deal with and especially since I was really a nobody to them.

Yes, the 500 efi injectors are NOT 32 lb, im sure, however, the dead band is in excess of 1 ms and the aftermarket ones much shorter for them to outflow them by so much at every rpm/pw setting on my machine. Its not just these particular ones either, ive tried others in past. I also have some 50 lb delphis and flowed them against a couple of different 48 lb standards, holleys, racetronix house brand ,etc and they come up low. Thanks for sharing John, Smitty