Stock Catalytic Converter Measurement ?
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Yes, and thank you, It's the original and I didn't lay down to measure it, But I have a set of Summit shorty headers going into the original ' Y ' pipe which is a 2.5 pipe and on the exporting end is the Gibson 3" exhaust pipe ! Does this make sense to you ? I want to replace it with a 3" and 3" high flow converter. Thank you !
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Yea. I see what you are doing. One note, be careful going too large in diameter with your exhaust system. I put 3" from my jba headers all the way back to a flow master and 3" tail pipes. I lost significant back pressure and power. I put up with it for about a year and then had it redone and did 2.5" from header to muffler, then 3" tailpipes. Changing it to a smaller diameter brought my power back.
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JT another thought: What Pikey said plus if you go to a high flow converter and pipes you may have to get a new ECM tune to pass emissions tests if you have that where you live. Not sure whats required where you are but I had a friend do that on his car here in Colorado and he failed emissions due to the high flow cats. After re-tuning the ECM it passed.
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Hay Silverado002, you just hit a good point. I bought a 'Jasper' replacement engine. Beautiful from A to Z, but I also installed a Edelbrock TBI tourque increasing manifold #3704 from Summit. And once I put it on for the next few miles it seemed to have just a touch of lag. That engine is on it's 500 miles brake-in period, but it make me wonder if the addition of faster flowing intake and faster flowing exhaust. Up until now emission's wasn't a big deal because I drove less the 5000 miles in a year, thus making a emissions test exempt. I have a set of summit shorty heaters going into a stock ' Y ' pipe , through the big 25 year old converter then stepped up a 1/2 inch to make the connection to the 3" Gibson exhaust system. Althogh, is this something that can be 'Tuned' in the PCM ?
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I don't think you overload the ECM but I can't say for sure if your ECM can be tuned as I'm not that up on it. I do know that when you change from stock intake volume and exhaust you end up changing the parameters around which the ECM and motor were calibrated. Since you are changing the flow characteristics in and out it would seem to me that a change should be made to the fueling tables in the ECM. Hopefully the ECM you have can be made to correct for any changes to the intake and better flowing exhaust. Also, I know from others telling me that if you eliminate too much back pressure from the exhaust you loose some power and torque. Just me thinking out loud.
I'm curious. How does your state know you are driving less than 5K a year. Good luck.
I'm curious. How does your state know you are driving less than 5K a year. Good luck.
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I installed the Edelbrock intake manifold #3704 and the first few days it had a ultra- hesitation , but that cleared up after a few days. Now on that end, when we did the engine we changed the fuel injectors and I got a 'Matched Set' from a company that does a lot of injectors and that work OK as we put a new O2 sensor in 'Y' pipe, I think it was in the pipe and not the manifolds. I thought if the intake is using more air/fuel mixture, then it would balance out with increasing the exhaust flow ?
The cars mileage is logged into the computers at Harrisburg DOT every time it gets state inspection.
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Yes, but it can learn or right ? I ask because the slight lag after the Edelbrock manifold seems like it compensate for the change and the lag is gone ?
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