Injector Balast Resistor Which One Is Needed?

[OGR88 R32]

hey i got a rb20det just got the ecu chiped and with my injectors apparently i have to run a ballast resistor all i know about the injectors is they came in a hks computer and injector pack they are 550cc and say denso on the side the injector impedance is about 2-3 ohms...and if i use them without the resistor it will fry the ecu?

6.8 ohm 15watt ballast resistor sound right?

also have a custom twinfeed fuel rail will the stock fuel pressure regulator be alrite?

rb20det

-fmic

-pod

-bov

-hks adjustable cam gears

-550cc injectors

- twin 10mm lines from tank (stock fuel line is used as a return)

-gtr fuel pump set up externally

-rb25det turbo high flowed with a vl .60 front cover (built to hold 22psi)

-3.5" dump 3" cat back

-q45 afm

-18psi

aim is 350rwhp but am expecting anywhere from 300rwhp up

its a r32 gts-4 should i run it on the dyno is 4wd or rwd?

also what does it have more hp in? ive had it on the dyno completely stock in rwd and get 175.4 rwhp

cheers vance

Edited December 13, 2006 by OGR88 R32

[GTRgeoff]

I think 10 ohm is more on the money. At least 10 Watt as well.

I don't do hp but have seen a 20 run 260rwkw as a stock short engine. It was backed off for a little longevity.

[OGR88 R32]

alrite anyone else like to verify it?

[Steve]

high impedance injectors should be around 13 ohms

[Cubes]

All the Nissans run with 5.5-6ohm resistor packs as do a lot of other cars that I know of. Honda, Mazda etc.

I picked up a R30 Skyline's resistor pack for next to nothing.

I did a few calcs a while back, from memory it turned out I required some where around 17w resistors.

Good 17w 6 ohm resistors are difficult to get at a reasonable price. A total of 6 worked out to nudge close to $100.

Grab an R30 or 280ZX resistor pack from the local wreckers, much cheaper and the resistors are designed for the purpose.

The male plug can be purchased from your local autostore for ~$2.95, the less soldering required the better.

I wouldn't be reving or driving the car if your not running a resistor pack, it WILL cause the injector drivers to fry and worse case catch fire. It 'may' be ok on idle and at low rev's but mid to high rpm and your most definitely asking for trouble.

Be safe, just dont drive it until its sorted.

IF you decide to go separate resistors here's what 'should' be used.

http://www.rx7store.net/product_p/injector%20resistor.htm

Remember thats in USD.

Attached below is a pic of my R30 resistor pack. Looks the same as the GTR item just with a different plug.

[DFAULT]

pretty sure you dont need resistor for the denso 550cc

i've just recently purchased some of these

straight bolt in, only need the plugs

[OGR88 R32]

yeah they are out of a toyota and ive got the plugs sorted i really need to get it goin by the weekend so il see if i can get my hands on the r30 resistor pack seems like the way to go thanks heaps for all the help everyone especially cubes

cheers vance

[kudos.motorsports]

As a rule of thumb if you're using a JECS or Denso injector and have to change the plug then the unit is of a different impedance. The best way to check is to use a multimeter and test the resistance.

[SirRacer]

hey cubes, have you got a pic of what the resistors look like without the cover on top of it?

i brought a resistor packing thinking it had covered and when it turned up i was missing them, so i want to confirm whats happening

[Cubes]

SirRacer, I'm unable to remove the cover its stuck on there.

If the dude has sold u a resistor pack without the cover and not told you then he has done a shonky.

[GTRgeoff]

I just measured up.

GTS25t injectors are 11.5 ohm

GTR injectors are 2.5 ohm

Toyota 440cc injectors are 3.5 ohm

Hope that helps

[Wheezy]

GTS25t injectors are 11.5 ohm

Geoff, am I right to guess that RB20DET (R32) injectors are the same resistance as the R33 RB25 ones? and the only difference being the wey they feed into the engine? Ive never sat them side by side...

cheers

-Jez

[GTRgeoff]

So I have been told. Never taken the time to measure them.

[Cubes]

I just checked my Silver top RB20DET injectors.. 13.8ohms. :S