1G My GSX sounds like its hitting a rev limiter at 4,300RPM

[Caleb4G63T]

So, Yesterday I got a 1991 Eclipse GSX it's manual. It has a 255 Walbero fuel pump, and 560cc Evo injectors. The problem started after I put in the bigger injectors (I Think). When I rev the engine up to about 4,300RPM, it sounds like its hitting a rev limiter. It sounds like is from 4,300, and the higher I rev it, the more severe the sound gets. I checked the spark plug wires, and the gap between them, they are fine. There is no boost leaks, so that is not a problem.

 

[pauleyman]

How are you tuning these injectors. If your answer is nothing take those out and put the stock injectors back in

 

[Caleb4G63T]

How are you tuning these injectors. If your answer is nothing take those out and put the stock injectors back in

My answer is noting, but how would i tune them? I didn't do that with my 1990 TSI, and those work fine.

 

[lasershark]

You need something to compensate for the extra fuel. The ecu doesn't "know" there are bigger injectors so it "opens and closes" them as if they were still the stock 450's. Ecmlink is the best solution but if that is out of reach a safc "would work" but until you have a way to compensate or tune you need to run the stock injectors. Do some reading around this site it will help you out dramatically.

another side note since you are new... Start a vehicle profile, As you make modifications... keep it up to date. If you post another problem people will be able to see what you are working with and be able to help easier.

 

[Caleb4G63T]

You need something to compensate for the extra fuel. The ecu doesn't "know" there are bigger injectors so it "opens and closes" them as if they were still the stock 450's. Ecmlink is the best solution but if that is out of reach a safc "would work" but until you have a way to compensate or tune you need to run the stock injectors. Do some reading around this site it will help you out dramatically.

another side note since you are new... Start a vehicle profile, As you make modifications... keep it up to date. If you post another problem people will be able to see what you are working with and be able to help easier.

I have the boost dialed up to 16LBS, and a cold air intake. I just put the stock injectors back in, and it's still doing it, but not that bad. Thank you.

 

[partylikeits82]

Try disconnecting the battery for a half hour or so to reset the ecm. Chances are your fuel trims are way off after having the wrong injectors in.

 

[lasershark]

I have the boost dialed up to 16LBS, and a cold air intake. I just put the stock injectors back in, and it's still doing it, but not that bad. Thank you.

Try lowering the boost a little more...
Is the car stock minus the intake and pump?

 

[Caleb4G63T]

Try lowering the boost a little more...
Is the car stock minus the intake and pump?

I took off the EGR valve, and put a block off plate, I also ported the exhaust manifold, and I am porting the intake manifold.

 

[lasershark]

You can skip porting the intake manifold if you are referring to the runners. The stock 1g manifold is good for some serious power.

 

[Victor1]

Does the car break up? Or does it simply not accelerate more?

 

[TehRiceBandit]

My answer is noting, but how would i tune them? I didn't do that with my 1990 TSI, and those work fine.

So you're running a 50 trim untuned?

 

[Caleb4G63T]

No, on my Talon I have the 50 Trim. I fixed the problem, I just needed to flush my blinker fluid.