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7.4 build to 8.1

1999 Tahoe 4x4

By 1999 Tahoe 4x4
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1999 Tahoe 4x4 Enthusiast

1999 Tahoe 4x4

Posted
Posted

To my understanding the 8.1 L is a stoked 7.4 L.

 

So I'm just thinking can somebody with e.g. a regular 3/4 ton and 7.4 liter under hood truck stoke the engine up to 8.1 liter, AND still continiue to use everything else under the hood.

 

Would that engine start and run? Would the computer be able to adjust automatically to the difference, would it have to be reprogrammed? Are the cyl.heads compatible or even the same at all? Would the intake work?

 

----> And I'm not asking if such a stoked engine going to be the same as an 8.1 L. I just want to know if it would work.

 

I know this all might sound silly to some of you, but I just have this questions in my head that bug for an answer.

:P

clm7214 Enthusiast

clm7214

Posted
Posted

Your answers are No, No, No and maybe. If you wanted to do that i would STROKE and Bore it 30 over, which would bring you over 496ci. That would require bottom end work, a cam, a retune and preferrably some head work. If this is your daily driver it would not be worth it. Its not as simple as putting in a stroked crankshaft. If this is a project vehicle and you have some time on your hands it could be fun. This is comparable to taking a 350 to a 383. There is plenty on the internet about bored out big blocks, it can be very worth it and alot of fun. 1000hp on pump gas can be attained from the big blocks. It all depends on your budget and your intentions.

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