Bigger injectors - Enrichment ?

[cpa]

I have a question for those of you running bigger injectors (290-320 cc) with a stock OBDII ECU.

Do any of you run the injectors without the JR fuel enrichment relay or JR Map converter? In other words, the only things regulating fuel delivery are an FPR (i.e. AEM) and FMU (i.e. Cartech) and the MAP sensor is relocated to the throttle body so it doesn't see boost.

[The LS Avenger]

Yep I got the Venom 310 injectors, removed the JR trick after going to a stepper pulley and Cartech

[cpa]

Can anyone help a brother out [img]redface.gif[/img]

[slvr-bullet]

290cc, AEM FPR, Cartech 2025i, map mod and relocated IAT sensor to the back of the JR manifold..

[Holden]

10psi boost. Cartech FPR. 320cc injectors. I still have the JR circuit installed.

I don't want the ECU pulling timing due to heat.

[217gsr]

Which one is the IAT sensor? Is it the round-topped one that used to be held into the manifold by a single screw?

[cpa]

<BLOCKQUOTE><font size=2 face="Verdana, Helvetica, sans-serif">quote:</font><table border="0" width="90%" bgcolor="#333333" cellspacing="1" cellpadding="0"><tr><td width="100%"><table border="0" width="100%" cellspacing="0" cellpadding="2" bgcolor="#FF9900"><tr><td width="100%" bgcolor="#DDDDDD"><font size=2 face="Verdana, Helvetica, sans-serif">Originally posted by slvr-bullet:
290cc, AEM FPR, Cartech 2025i, map mod and relocated IAT sensor to the back of the JR manifold..</font></td></tr></table></td></tr></table></BLOCKQUOTE>


This is exactly the setup I have (assuming I can get the injectors to work), except I didn't "relocate the IAT sensor". When I installed the MAP Converter, I soldered back together the IAT wire that was previously connected to the JR fuel enrichmnet relay that was removed for the MAP Converter. However, I didn't touch the IAT sensor itself.

How and why did you do this and where on the manifold did it you mount it? Do you have the IAT wire hooked up on your MAP Converter then or did you leave it disconnected?

[slvr-bullet]

<BLOCKQUOTE><font size=2 face="Verdana, Helvetica, sans-serif">quote:</font><table border="0" width="90%" bgcolor="#333333" cellspacing="1" cellpadding="0"><tr><td width="100%"><table border="0" width="100%" cellspacing="0" cellpadding="2" bgcolor="#FF9900"><tr><td width="100%" bgcolor="#DDDDDD"><font size=2 face="Verdana, Helvetica, sans-serif"><font size=2 face="Verdana, Helvetica, sans-serif">Originally posted by cpa:
This is exactly the setup I have (assuming I can get the injectors to work), except I didn't "relocate the IAT sensor". When I installed the MAP Converter, I soldered back together the IAT wire that was previously connected to the JR fuel enrichmnet relay that was removed for the MAP Converter. However, I didn't touch the IAT sensor itself.

How and why did you do this and where on the manifold did it you mount it? Do you have the IAT wire hooked up on your MAP Converter then or did you leave it disconnected?</font></font></td></tr></table></td></tr></table></BLOCKQUOTE>

Usually the IAT sensor is "plugged" into your intake system (AEM CAI or whatever). This sensor senses the intake temperatures and adjusts the delivery of fuel (so to speak). So the reason it being in the intake system is to "fool" the ECU in to thinking that the intake temps are cooler than they really are, which in turn adds more fuel (cooler/colder air = more fuel).

Remember, air is being sucked in and then compressed before entering the combustion chambers. Compressing the air before hand heats it up. Relocating it to the back of the JR manifold makes the ECU see "true" intake temps, allowing fuel to be adjusted correctly according to intake temps. I did this because @ the dyno, it was dumping so much fuel @ 3000-3500 and up and wasn't even registering on the graph. Someone here suggested to relocate the IAT sensor to help remedy the problem.

The spot is on the back of the manifold (right side looking from the front) and looks like some sort of a diamond shape covered by a white piece of cardboard paper and 2 screws.

You'll need an IAT sensor from a '92-95 (I think) civic ex/si and connector. Just splice into the existing wires from your stock one but don't put it in the intake system. Just disconnect it and tie it up out of the way.

I don't have a MAP converter like JR's. I'm using the J&S v2 to modifiy the MAP signal. I also got rid of the JR enrichment relay and just rewired the wires.

<font color="#a62a2a" size="1">[ July 12, 2002 11:04 AM: Message edited by: slvr-bullet ]</font>