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Old 07-23-2008, 02:34 PM   #1
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Default 78mm throttle body on a 5.3 intake?

Will a LS1 78mm throttle body work on a '00 5.3 truck intake manifold?

I'm thinking about getting a ported 78mm TB when I change the engine out to a 5.7 long block, but use my 5.3 intake manifold to keep everything matched up on top. I don't want to go the pulley relocation route, etc. needed with an LS6 intake.

Would I see any gains over just using my stock TB from the 5.3?

Any experienced info or opinions would be appreciated. Thanks.

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Old 07-23-2008, 03:05 PM   #2
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the stock truck throttle body is 78mm. Just get it ported and polished

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Old 07-23-2008, 03:45 PM   #3
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I haven't had mine off to measure it, but I understood the stock 5.3 throttle body was 75mm. Are there any differences between the LS1 and cable drive truck throttle bodies?
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Old 07-23-2008, 03:58 PM   #4
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The throttle cam on the side is keyed differently. You'll have to relocate your throttle cables. Not worth the hassle IMO...they are either exactly the same size or close enough that you won't notice a difference.

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Old 07-28-2008, 12:09 AM   #5
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It's not worth any HP between the two.

I port the cable and DBW TB's for $55 shipped. If you're interested feel free to PM me. There's a LOT of material that can be removed from the truck TB's for a nice throttle response gain.
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Old 07-28-2008, 12:09 AM
Ford F150

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2005, 53, 53throttle, 75mm, body, gm, ls1, performance, ported, porting, size, spartan, ssr, stock, throttle

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