Gotch ya. Sorry about me butting in above. I didn't realize all the info/work you and Smitty did on this subject until I just read the whole thread a few minutes ago. I must have been on vaca while this thread was happening.

Are these (bottom ones) poor knock-offs ? http://www.ausinjector.com/marine-injectors/

I would like to install new injectors in my 500efi but I am also changing to a Holley HP EFI controller on my engine.My engine is stock at the moment, but I am looking to upgrades next year, like larger heads and a procharger and upgraded fuel system. Can I use an injector that is similar but not an exact replacement and then tune for that with the Holley. Should I go with a larger injector to allow for future upgrades or is that not practical to run larger injectors on a stock motor? Haxby has offered to help me with a base tune to get me started.

Any help would be greatly appreciated.

Thanks,

Jason

You can buy 60 or 80 lb drop in injectors from just about anywhere,however you cannot run your stock tune with them until you add your power adder down the road, you would definately have to have your mefi tune re-wrote or you would gas up the oil, wash cylinders and run pig rich. I have tested the siemans deka match flowed sets i get from racetronix as a dealer, they do a good job ensuring they are real close, smitty

Thanks for the reply Articfriends. I am changing over to the Hollley HP EFI ECU now to use with my stock motor for the time being until I have funds to do the upgrades I would like. Do you have a specific injector that you would suggest I run in my stock 500efi motor now with the Holley ECM .

I am interested in this. Just thinking ahead for rebuild time and want to get out of these old injectors and ecm.

Size the injectors for future hp level, 60 lb go pretty far vs stock 36/38 lb, siemans deka match flowed 60 lb drop right into a 500 efi intake. 80 lb will support more hp but you end up getting pw's in the low 1ms to get it to idle, what is your future hp goal, i will crunch the numbers if you want, Smitty

Personally if you are going aftermarket eci I would buy a set of injector dynamics id1000s. They are expensive but one of the best injectors out there imo. You will have no idle problems and they are very easy to tune. You will also have plenty of room to grow.

Ive had great results w siemans deka injectors at about 50$ each, when you get into 80 lb and larger injectors however they still have about .8 ms of dead band, it doesnt matter whos you get. When tuning w mefi you end up w pw around 1.2 to 1.4 ms and .8 of that is dead band, a .1 change will immediately change the afr as you are only tuning .4ms or .6/.7, holley ecu might have a "finer" resolution but again, ALL injectors have dead band. When you get into 120lb etc you start loosing ability to fine tune idle, thats why i feel its best to size injector appropriately, Smitty

I agree to a point. A quality ecu will have good fueling resolution. I'm not sure if the Holley does.

I run Injector Dynamic ID2000s (225lb injector) with great success on my little 352 street car. I can idle it down to 500rpm(just for testing) at a 14:1 af and hold it there. The IDs are very linear across the range. My ECU has very good fueling though. I was concerned running such a large injector on a street driven engine. I'm glad I went with them as I was tired of buying new larger injectors as I turned up the boost. I stopped at 83s and jumped right to 225s. No more injector size worries for a while, I hope.

Id's are a great option, but expensive.

it almost sounds as if you are better off with 60 lb injectors and a tune to trying to match the stock ones.