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Discussion Starter · #1 ·
OK so I have my minivan going pretty good now. Few issues/questions though...

First, my complete setup list:
2.5L w/ Automatic
G-head, ported
ported exhaust manifold
Turbonetics S60, near brand new
2.5" SV to 3" exhaust
W2A intercooler system
FWD-P St5 cal w/ +40s and 3-bar
Colder plugs (cant remember which ones... RY9 or something like that)

Issue: After a few runs, and I think it did this before I swapped head/turbo, at random it seems that suddenly I am running REDICIOUSLY rich... I mean, just cruising I am 10.5-11.5 AFR. After a few minutes of driving, it will start to lean out back to 14.7. My best guess is that the fuel regulator is getting stuck... any other ideas? Its still the stock FPR, which I do plan to change out regardless...

Question: I am also running the stock pump... plan to change that of course. I tuned from 13psi on up of boost. I hit 18psi holding and ran AFRs of 11.5:1 on average... 20psi was 12:1 on average... I really don't want to go any leaner than 12:1 as I need full reliability in this rig. What is my limiting factor for more boost at this point?

Thanx gang!
 

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Could be the stg5 cal causing the rich condition .... same thing on the boost limit. You'd want the cal to provide enough fuel beyond 20 psi. A bigger fuel pump is needed right now too.

I'd get in touch with the vendor and see if you can get a tweaked chip revision outlining you're goals.
 

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wierd. Just because you're lean at 20 doesn't mean you'll be leaner at 21+. It's all in the fuel curve. The fuel curve has to keep up with the boost level. Now if you're running out of fuel via the fuel pump not keeping up that's a different story not related to the calibration. Need a fuel pressure gauge to watch what's going on. Don't waste time on a AFPR. If the cal is correct you don't need one. You could be rich at 10psi and lean at 20 and trying to adjust the fuel pressure is gonna make you ok at 10 and dangerous at 20. Or vice versa.
 

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Discussion Starter · #5 ·
Good point. I would like to replace the FPR regardless simply because I believe it to be sticking... guess I just have too much money :D hahaha

Anywho, ill have to try a bit higher when I get some time to play with it. As well as an electronic fuel pressure gauge setup.
 

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Could just be your factory oxygen sensor is bad and giving the computer false info, I wouldnt want to turn the fpr down if I was at 12-1 afr already.

Fuel pressure gauge is a great idea, hoping the fuel pump is ok sucks because ive had two rubber fuel injection hoses rupture inside the tank and two pumps go bad, one was brand new supposedly hipo pump but at least my gas tank bolts come out easy lol.
 

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Yes!! you need a charge air temp sensor on all cals that use an intercooler. The reason that you may be rich sometimes and lean others is that the computer can not add or subtract fuel dependant on whether you have hot or cold air coming throught the IC. Without the CAI sensor, the ecu lit the check engine light and went into default mode. The wiring is pretty simple. it is a 2 wire set-up, one to ground, the other to the #21 pin connector on the ecu. If you already have you car together and can't drill and tap the intake manifold where the sensor would normally reside, then you can plumb it into the IC tubing coming out of the cold side of the IC.
later,
Cindy
 

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did a real fuel pump BTW make it on your mod list? The fuel pressure is unreal up there at 20 PSI. A stock pump will fall down as the boost gets up that high. The amount of fuel to each injector changes too. The wide band shows all combined, you could be 13+ on one cylinder lol. What about getting a fuel harness from a 88 up T2?
 

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Discussion Starter · #12 ·
I would hate to do a whole harness if putting a ground and 1 pin in is all that is needed ;) But if I found one at a reasonable price, probably go that route.

The fuel pump will be replaced by the end of the month for sure!

As for the feel of the setup... its pretty laggy when compared to the mitsu turbo, so don't expect any "real" power until about 3K but it hits its peak at 4K and takes off like a rocket! Once I get everything tuned out, I wouldn't be surprised if I pull some 13's pretty easily.
 

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I would hate to do a whole harness if putting a ground and 1 pin in is all that is needed ;) But if I found one at a reasonable price, probably go that route.

The fuel pump will be replaced by the end of the month for sure!

As for the feel of the setup... its pretty laggy when compared to the mitsu turbo, so don't expect any "real" power until about 3K but it hits its peak at 4K and takes off like a rocket! Once I get everything tuned out, I wouldn't be surprised if I pull some 13's pretty easily.
i dont mind the lag i see traction issues in my future already so some lag will help and how ported is your top end
 

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Discussion Starter · #16 ·
Automatic dood ;) But I have yet to try with the raise in boost... I was running 13psi when I tested it, where the mitsu on 15psi was hard to launch without getting my spin on! :D After I tune the last of it, I am sure traction will be pretty well gone with my current tires.
 

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un do the smec connector, take the small blade on a swiss army knife and pop the red insert up .030-.050 and hold it with your finger. Now put the blade between it and the screw in the center and twist the blade till it pops out. Now you can release the lock pin and pull the wire out and put your new wire in. Just did it tonight for wiring my wideband into the stock ECU.
 
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