Injector selection

[HarryB]

So, I am torn between using a set of Grams 350cc injectors (Bosch EV14 essentially), or a set of reconditioned Denso RX8 units (420cc). Presumably, the EV14s have a better atomization, which in theory would be better for idling and economy, however I like the idea of extra headroom with the RX8 units (to my calcs the Grams would be over 90% DC to cope with approx. 200 motor hp)

Thoughts?

[Greasemonkey2000]

Go with the newer EV14's. There are plenty of affordable options like the Force Flow 640cc.

[HarryB]

640cc are a bit too much for my intended use; nice to have headroom but larger injectors may prove harder to control at low duty cycles making idling tricky. Ideally I would need something at 400cc range.

[Greasemonkey2000]

You are going to be using a aftermarket ecu correct? :shrug: If so then you could use 1000cc(QUALITY ) injectors and idle, etc will be BETTER than older technology 400cc.

The ForceFlow 640cc injectors(essentially stock ford mustang gt500 injectors) was just an example, obviously if you want to go smaller then you can get smaller cc EV14s. Also remember if you ever want to use e85 than you need to oversize them.

I'm no expert but have done plenty of reading. Don't take my word Harry, read up! :)

[NCGreasemonkey]

What Chad said.

If you are running a non-OEM ECU, which I assume you are, Dyno tuning will get you your idle and trims. The injectors will 'listen' to what they are told buy the ECM and what it reads from the MAP and A/F sensor.

[Blueiii]

A bit late to the party.... RX-8 yellow injectors are direct drop in and 420cc, give or take. If you join the RX-8 parts group on facebook you can usually find used injectors cheap. (I paid $60 for mine, then another $100 to have them cleaned / flowed by witchhunter.)

[BRGNA8]

is it worth anything to upgrade the injectors on a largely stock motor?

[Blueiii]

Do you have a tuneable ecu?

I should have dyno numbers within the next 3-4 months for a "stock" motor with bolt-ons and a tune using the rx-8 injectors.

[joe morreale]

I have Force Flow 640cc injectors on my 2001 car, with Megasquirt. Cheap CAI and exhaust, otherwise stock. More power throughout the rpm range, easy starting and smooth idle. I'm using 1.12ms deadtime. Car still gets up to 28 mpg.