My Edelbrock has lag below 3000 rpm

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My Edelbrock has lag below 3000 rpm

Postby PsychoMX5 » Sun Jul 15, 2018 8:47 pm

My Edelbrock supercharger is installed, and the car runs fairly smoothly. However, there is a noticeable lag below about 3000 rpm. See attached dyno graph which shows torque is lower than stock below 3000 rpm. There is also a very slight throttle surge when lifting off the accelerator.

I've taken some data logs; one is linked here

The log shows KR is 0 up to 2600 rpm, then quickly increases to a max of -1.62 at 2879 rpm, then decreases to 0 by 5700 rpm. I thought it might be an issue with the bypass valve, but I got underneath with a borescope and confirmed none of the hoses are kinked or crushed. Any ideas what the problem might be?
Dyno before-after.JPG
2016 Club MT, Edelbrock SC, RS Super Q TTSS, Progress Springs, 17x8 6UL w/Yokohama 235/40-17
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Re: My Edelbrock has lag below 3000 rpm

Postby Brian » Mon Jul 16, 2018 5:40 am

My wife's RF on stock header and CARB tune for comparison. Not sure why yours is slow to ramp up by comparison but I would look at bypass valve first. Had a few folks hit the bypass valve during install with result the arm attached to it was bent or broken.
Carb-Header.jpg (148.34 KiB)
Brian Goodwin
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