studders in vtec?

Phantomhatch · Post by **Phantomhatch** » Fri Feb 02, 2007 11:30 am

Well having a very intersting problem that kinda been buggin me for a while

-I am using the s300 on the stock p28 map. car is at 10psi and 450cc dsm

-- what the problem is when the car changes over the vtec it falls off in power and sounds like it misses. but it dont shutter.. another thing i noticed that the timing is set for 25* and in the dattalog its 29* i tried backing the timming off and it still wont change still stays at 29*

-- another thing is when i start the car the a/f go straight to lean off the chart lean. I have tried adding fuel in the rpm rang for idle and there is no change can get it to richen up for anyhting. the base timing is set dead on witht he timing light and it logs the 16* at idle the fuel pressure is set correct

-- another questions is that i was running these injector with out a resistor box off the stock ecu with a vafc tune for over 4 months with no problems. do you HAVE to have the resistor box?

Post by **Spunkster** » Fri Feb 02, 2007 11:39 am

You must have the resistor box and we do not recommend using DSM injectors.
http://www.hondata.net/forum/viewtopic.php?t=432

Make sure you are adjusting the correct tables. You may also hav esome ECT or IAT compensation numbers that are increasing your timing.

Phantomhatch · Post by **Phantomhatch** » Fri Feb 02, 2007 11:42 am

Spunkster-- thanks for the info!

-- what kinda injectors you recommmend like RC or percision turbo?

-- and low imped correct?

Post by **Spunkster** » Fri Feb 02, 2007 2:49 pm

We recommend RC saturated (high impedance) injectors.

Phantomhatch · Post by **Phantomhatch** » Fri Feb 02, 2007 6:10 pm

would them RC's have to be used with a resistor box or with out?

P.s Thank you for the all the info so far its greatly appreciated

smracing · Post by **smracing** » Sat Feb 03, 2007 11:24 am

Does Hondata recommend against using low impedence injectors? I was looking at running some Bosch or RC low impedence injectors on my turbo car. The Bosch are one of the few that can handle fuel pressures of 60-70ps on a continual basis, plus with low impedence injectors they will work better at low durations.

Asc4130SD · Post by **Asc4130SD** » Mon Feb 05, 2007 9:08 am

I think Honda requires high impedence injectors, there swtiching curcuit (Transistor (mosfet) driven) was designed around using high impedence injectors. To Run Low impedence injectors would overheat the curcuit and eventully burn up the transistors. Even with a resistor box, all your doing is increasing the resistance of the injectors, which may or maynot be the right value the ECU needs to run the car as the ECU was designed for. I personally would ont risk burning up $500 S300 over $280 injectors. Its not even the money, but the time and hassle of messing with the injectors to make them work and being broken down in the middle of nowhere. knowing you had the wrong injectors. time is money! "Do it once and do it right" that my mato :)