carburated ls1

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Jun 13, 2013 | 09:13 AM

billymgb1000

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From: harrisville R.I

carburated ls1

I have 4.8 with a stock cam in my 1974 mgb I have a edelbrock 600 cfm on her and was wondering if I should change the jets to smaller for this motor or will I be ok

Jun 13, 2013 | 09:21 AM

PowerAdder

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From: Rochester

Is this the off the shelf Edel 600? If the jets haven't been touched it will work great. Don't let the small cubes fool you these motors flow allot more than your dad's sbc! have fun man!!!!

Jun 13, 2013 | 07:08 PM

fox12303

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I agree a 600 would be perfect on the 4.8L. However I would check the stock calibration as the step-up springs usually need to be changed at a minimum. If you have a tip-in bog or rich cruise condition you will have to do a little tuning. Start by test driving it to get a good feel how it's running, purchase a calibration kit and go from there.

Jun 14, 2013 | 02:44 AM

billymgb1000

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From: harrisville R.I

Quote:

Originally Posted by fox12303

thanks I did not know about a calibration kit when I hammer her I think she rich from the smell I will do that

Jun 16, 2013 | 12:18 PM

Pop N Wood

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Did you really say 74 MGB?

You might consider a wide band O2 sensor. That is by far the best way to dial in a carb. You also might try posting in the carb specific forum if you want to dig deeper.

Jun 17, 2013 | 12:06 AM

1981TA

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From: Saint John, IN

What model Edelbrock carb? Nake sure to get the right needle and spring tuning kit for it. The wholw process is pretty straight-forward. As mentioned by Pop, a wide band O2 sensor is a good tool to have.

Jun 17, 2013 | 12:37 AM

bczee

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From: Concord, CA

One thing to consider is how much the 4.8L can really draw in CFM.. there are calculators to use. .but a 4.8L at 6500 rpm will draw about 475 CFM.. even a 350 will only draw less than 600 cfm.. (559).

With a stock engine, and if your expecting to use a 600 cfm carb.. you will most likely need to so some tuning with the Jet and Rods.

just my 2 cents.

BC