To Irishcarbomb and Sorace

[JBz]

you seem rather knowledgable on the FI setups as does Sorace. Im dinkin with a FI setup in my spare time a 1200 FI unit on a 1200 engine that is gutted and going Microsquirt. My ?? is injector sizing of the stock denso injectors. I really don't want to run resistors for the factory low impedence injectors so Im going to the high impedence saturated ones. Back to the ?. According to the injector chart the factory ones are rated at 280cc. The minmum required for 95HP is 157cc. Just wonderin why they went with the 280cc injectors. I want a crisp good idling engine with torque and 280cc seems high. Can You share a thought or 2.. Other members with knowledge are welcome to chime in . Thanks JB

[irishcarbomb]

injector ratings are posted at 100% duty cycle (time the injector is open) at 3 bar/43.5 psi of fuel presure. you don't want to run at 100% duty cycle all the time, really you want to stay at or under 80%

go to this website http://witchhunter.com/injectordata1.php

if you stay with the denso top feeds and just click through the 195500(If you stick with those,most should fit the GL1200 fuel rail) injectors until you see one that is high impedance(more than 10 ohms) with the flow you're looking for. For naturally asspirated I'd say in the 200-280 range are fine.

these seem like good options




Some good deals can be had on ebay if you just search around a bit and find what application the injector was used in. I got a set that flow a bit more from an older Ford Probe. Had them cleaned and tested locally for about $100 and they look brand new.

[Casper]

Good advice ICB, Like JBz I am sourcing injectors for my EFI setup, and the website you posted is a big help.

Cheers,

[socrace]

Think of resistors this way: they do get warm, so do you want to heat up external resistors or heat up injectors full of fuel? I'm using external resistors with the stock LTD injectors. They have an idle pulse width of around 5 ms or so, about the same as a saturated injector of the same size. Honda used external resisters also, but not sure what resistance they are, ebay sellers wanted way too much for them, maybe because of the hi tech looking cooling fins! Mine are 10 ohm 10 watt ceramics, one per injector.

[JBz]

I have the original 1200 resistor that looks like a finned icecube. with 3 wires an input and one wire to each bank of injectors. I have a complete 1200 FI unit but it has all kinds of other gizmos and the brain is too large for a naked bike. This will be a challenge.Ill hang loose on the injectors for a while as I got a lot more to do. Matt at DIYAUTOTUNE has been a lot of help. Why am I doing this.????? an old gear head or Just cuz I want to and keeps my brain active maybe overactive ......jb presently I have this 85ltd engine in a 75 frame but might move it over to a 82 frame. Just test bed and fab frames but both are titled and I can go either way. Might even put it in my 84 standard JB

[socrace]

Most OEMs have abandoned use of external resistors. The benefits are really pretty minor. If I needed new injectors, would probably go with built-in resistance. Did a search some time back and found 90-92 Ford Probe GL 2.2L seemed to fit stock LTD system with right flow and high resistance, Motorcraft CME 4682. Have not tried it to make sure though!