Vortec GEN VI L29 454 Big Block swap people need advice


Comic Book Super Hero
Oct 25, 2019
Colorado Springs, CO
Mine came from a motorhome as well but I have the stock Gen VI oil pan. You switched to a stock Mark IV pan?

Motorhome was MarkIV era, engine was replaced with a Goodwrench crate at some point. So I'm assuming here that it's the MarkIV pan, though seeing how it was a GenV service replacement it could be a GenV pan come to think of it. With the block being GenVI, I figure it was purchased after the horrible GenV was discontinued. It's quite the mish mash, but it's all bolted in there with ample clearance.


Sep 14, 2014
Elderton, Pa
The pans are different between the Mark IV & Gen VI. A aftermarket Gen VI "muscle car" pan might be a fix. Use the Chevelle for the base of the searches. OE car Mark IV 4qt pans fit our frames. As for block side mounts, '73-'88 A/G are the same for BBC & SBC.
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Feb 16, 2019
Phoenix, NY
I am thinking I either raise the motor mounts which still might not give me enough clearance and might put the trans to close to the floor and yoke angle might be a problem as well.
Modify the existing pan which I will still be able to use the existing pickup.
Buy a new pan, pickup, etc.

ugh, I was so happy to get this in....

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