Injectors - 50, 60, 65, 72, 83.. How to choose?

Mike8675309

Registered User
O.k. I thought I'd be looking for 60lb injectors. But now I see folks selling 65's, 50's, and the list seems to go on and on.

Say on a 3 year plan to 500rwhp. So year one is going to be Under 300rwhp. Can I get an injector that'll work at year one, and still be "safe" at year 3?

Or will I need to swap out injectors at year 3 anyway so get the cheapest good 42lb units today?

Thoughts?
 
Anything over 60s will require switching to a low impedance injector. Doing so will require wiring in a low impedance peak and hold injector driver or a set of resistors. I'm using a pair of DSM resistor boxes with the 84# injectors on the turbo car.

On an SC the injector sizing pretty much goes like this.

30# 300 FWHP
42# 420 FWHP
50# 500 FWHP
60# 600 FWHP

If it were me, I start with a set of 50# injectors and upgrade only when they can't supply enough fuel. You should be able to get about 375-400 rwhp from the 50s at stock fuel presure.

David
 
Mike,

My 60's????? were sold to me as 65's. May have something to do with the duty cycle they are giving you the rating at. I really have no idea but I was told the 65's I bought were in essence 60's.

That being said if you go larger then the 60's like David said youll need to get a bit crafty. I;d say 60's are to large for most applications
 
you can always tune the fuel down.. so why not go with the bigger injectors that you know will support the power you wanna make down the road?

if i were building a 500BHP SC id use a set of 60#'s if not bigger (at 500BHP compare the cycle duty of the 50# to the 60+#)
 
You get too big of injector, part throttle behavior can get touchy depending on the control system as you start to get into pulse widths that may be so small that the system can't control them. (I.e. like taking a 4" ball valve and telling the computer to only allow 32oz of fluid through it but requiring it to open 70% at minimum all the time.)

Thus the crux of the question. 50's sound right. I'm already considering that I may want to fab up a new fuel rail if I want to hit my final target and be reliable. At which time new injectors may be likely.
 
just remember... 50's are good for 500hp at the flywheel. You want to make 500hp to the tires, which of course takes alot more fwhp. At that point you may be pushing the injectors close to (if not more then) 100% cycle duty.
 
Ack... I'm going with the 60's from racetronix. They are on sale! $299.94 for a six pack and free shipping. Can't pass that one up.
http://www.racetronix.com/L107.html

Woops.. that's not flow matched. I will be getting flow matched injectors so I'm going to shop. Even if it costs a few dollars more I'd rather get it from an SC vendor.
 
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Well, if you want an SC vendor, I'd recommend Super Coupe Performance. Perhaps I'm a little biased since I buy all my modding supplies from there, but the service is great and the parts I've ordered have had minimal issues with going into my car. As far as price, they range from good values to expensive top-of-the-line stuff, so it's all about what you want in your car. Bill Evanoff, the owner, handles all the orders himself and is very knowledgable about the SC, and should be able to field all your questions even if you aren't totally sure of what to ask.
 
Injectors

Mike8675309 said:
Ack... I'm going with the 60's from racetronix. They are on sale! $299.94 for a six pack and free shipping. Can't pass that one up.
http://www.racetronix.com/L107.html

Woops.. that's not flow matched. I will be getting flow matched injectors so I'm going to shop. Even if it costs a few dollars more I'd rather get it from an SC vendor.


In case you didn't notice they offer the same injectors that have been flow matched for an extra $5 each, so they are still a good buy.

Charles
 
Most of our vendors will try to match prices, and Bill said his supplier can get him the 60lb injectors if I want. Yep I saw the flow matched ones, they're prices is what got me considering the larger units to start with.

I'm spreading it around on this project.
 
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