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Old Today, 12:32 AM   #1
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Join Date: Mar 2015
Location: Fort Worth Texas
Posts: 223
Speaking to mechanic about rebuilding my 350

I have a really nice 1972 K5 4x4 with matching numbers now at about 107k miles or more on the engine and trans. I went to see my mechanic and spoke with him about a rebuild and adding about 75-100hp over stock. I said I would consider stroking it and aluminum heads. I want to do it with the factory block and spend whatever is needed to make sure it never blows ( forged everything) top machine shop etc and preserving the matching numbers. He wants to put my motor in storage and put a stroker engine (he already built that is a deal honestly) in saying thats the only way to really protect the original matching numbers engine and add plenty of HP. I feel like he is saying what he thinks is in my best long term interest. What do you all think? What would you do if you want to add a noticeable amount of power and didnt mind spending 4-6k?

Thanks PG
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Old Today, 12:49 AM   #2
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Location: Safford,AZ
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Re: Speaking to mechanic about rebuilding my 350

Number matching really doesn't matter in these trucks. If you want to preserve the original engine, take it and put it in storage. 4-6K you could build a 406ci motor
1969 307, t350
1950 Chevy Wagon
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Old Today, 01:26 AM   #3
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Location: Back in Albuquerque
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Re: Speaking to mechanic about rebuilding my 350

I had the original 350 rebuilt in my k5 and added a roller cam - the block did not need to be decked so the stamped code remains intact. If you rebuild the original motor skip the decking if possible. Not many k5s have an original drive train.
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Old Today, 02:03 AM   #4
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Location: Orem, Utah
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Re: Speaking to mechanic about rebuilding my 350

I would put in an L31 Vortec - in fact, that's what I'm doing. A basic Vortec 5.7 with the HT 383 cam should get you in the neighborhood of 330 HP and 400 ft/lb of torque. It's a whole lot less than 4-6k. And in my opinion the Vortec can't be beaten for reliability.
If I didn't build it or fix it, it's probably not mine.
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