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SPFI-vrs-CARB., 1.8, Is there a difference?


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are you talking about swapping a carburated donor for the basic engine and keeping the SPFI? the compression ratios are different in the specs so it would probably mess up the ECU to not have the right compression. as far as just taking the whole thing out and replacing it whole sale it should bolt up as long as the model range is the same then you could replace the ECU with the one that matches the motor.

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are you talking about swapping a carburated donor for the basic engine and keeping the SPFI? the compression ratios are different in the specs so it would probably mess up the ECU to not have the right compression..............

 

:confused: ,That's it! .... o.k., thanks for the reply... Local guy has a carbed motor for sale and I was scratching my head if I could use it in my 88 wagon with SPFI. , so no go on that.

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that is my understanding. I was going to do the same thing, but the more I read it didn't sound like it would work right. that was just based on the compression ratios being diffewrent between the two though. you might want to wait for one of the more experiences swappers opinions thought.

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I have an ex-carbby wagon.. I put SPFI on it and it runs a bit rich (or so the Etest says) Runs great otherwise, ShawnW was impressed with it's speed Vs a Baja.. and I've even got a lift with 29's... But like stated, you probably would lose a bit of power, but then again you can advance the snot out of the timing and still run regular since the compression is lower.:banana:

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SPFI works just fine on the carbed blocks (EA81's too). The differences in compression are minimal (9:1, and 9.5:1) and definately do not warrant a change to the ECU. The ECU has room to adjust to differences in airflow, and an O2 sensor to adjust mixture on the fly. With the lower comp. you just get to advance the timing a bit. You will show an increase in both performance and mileage with the SPFI.

 

GD

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