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Discussion Starter #1
Hi all, so I have a 72 buick skylark with a buick 350, and a th350 trans. I want to drop a chevy 350 into it, and I'm looking to get an accurate idea as to what this swap will look like. I have read some posts that say it is an easy swap, that the chevy350 fits right in and bolts up to the th350 trans. however, i have also read that it does not fit, i need new motor mounts and a different tranny. Any advice?
 

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You need a Buick to chevy adapter for the transmission. It is nothing more then a thin piece for aligning the bell to the engine with the extra hole. You could always go thicker on the adapter for a rear motor plate then run a front motor plate that swoops under the balancer with clamshell mounts. You may have to change your starter. I am unsure about the motor mounts on the block.

Best of luck with the swap.
 

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Tailshaft length and firewall clearance come into play with the chevy trans. Not hard fixes but can be a headache if you do not factor than them into account.
 

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Discussion Starter #4
So I went with a 350 vortec motor. I now have a concern, as I know the vortec is a fuel injected engine, the distributor runs off computer. I have two questions.
1) I was wondering if anyone knew how to mount an old distributor onto this engine, and where, so I could run it carbed?
2) if running it fuel injected off a computer would cause a problem with the th350 shifting capabilities? Or if this could be bypassed with a pcm reprogram
 

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So I went with a 350 vortec motor. I now have a concern, as I know the vortec is a fuel injected engine, the distributor runs off computer. I have two questions.
1) I was wondering if anyone knew how to mount an old distributor onto this engine, and where, so I could run it carbed?
2) if running it fuel injected off a computer would cause a problem with the th350 shifting capabilities? Or if this could be bypassed with a pcm reprogram
Option 1 requires an intake manifold. Easy and been done 1000's of times. Option 2 is possible as well, but a little more complicated and demanding to tune.
 

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Discussion Starter #6
So if I were to buy an intake, where would I mount the distributor? And then I'd have to get an electronic ignition no?
 

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The standard large cap chevy HEI distributor will fit, your Buick is nothing more than a '72 Chevelle with different outer sheetmetal styling on it, virtually everything under the skin is the same. With a carbed intake, the distributor hole is already there, just install and go. You need a Vortec bolt pattern (to match the Vortec heads) carberated intake and you are set.

You will need '72 Chevelle small block engine mounts on the block and 68-72 Chevelle small block engine stands on the frame and then it will drop right in. Motor mounts and frame stands are both available from Chevelle Reproduction Parts distributors like NPD and Paddock.

The Buick TH-350 will need an engine adapter plate to fit, or you can use a Chevy TH-350....just make sure the Chevy TH-350 is the same length as your Buick TH-350 and everything will bolt up, including the driveshaft and shift linkage.

Some wiring for the starter, alternator, main battery cable, distributor may have to be shortened, re-routed, or lengthened to match with the difference in location on the engine between Chevy and Buick, but that is relatively simple..

The stock Buick exhaust won't fit up to Chevy manifolds outlets, so be prepared to replace the front half of the exhaust, or use Chevelle Small Block headers and fab a new exhaust system, or buy a prebent header-back exhaust kit from Jegs, Summit, or Hooker. The Jegs and Summit dual exhaust kits fit well. Just get one for a '68-72 Chevelle is quick and easy and you can install it to a set of headers yourself at home.
 

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Discussion Starter #8
So did some research on the engine I have and it's an lm7 which I guess is part of the Ls family, I also found an article that outlines exactly what I am going to do http://www.superchevy.com/how-to/engines-drivetrain/1401-how-to-swap-in-a-carb-equipped-ls-engine/

Now I have a few questions, I am following this to suit just about. Just had a question regarding the oil pan, seems these guys just like to rock a lot of Holley, and I was wondering if that oil pan was necessary, or if I could get one for an lm7 out of an 01 camaro and if that would clear the crossmember for the skylark?

Another question was

i would like to use the stock serpentine system. In which case I take it I would need to buy the 01 Tahoe alternator?
I was wondering if anyone had a link on how to wire a late model alternator into a classic gm?
(72 skylark)

I was also wondering what If I could use the 01 Tahoe power steer steering pump, and retrofit that into the skylark? If not, what power steering pump should I use, and will it mount to the stock serpentine system?

Thank you very much for the time
 

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1st, you aren't swapping a Chevy 350 intto your Buick if you have what they have in the article they attached. Do you have coil on plug (COP) and valve covers that look like what's in the article or no? If yes, then it's either a 4.8, 5.3 or 6.0 liter and that swap is tad more tricky than putting in a 'Vortec'. 2nd, not to bad if you're using a carb intake, but you need something to fire the coils. The simplest way is with an MSD 7 box.

Let us know exactly what you have. I have to admit that I'm not up on the LM7 term, but an LS platform engine is not the same as what is commnly referred to as a Vortec (even though the LS engine says 'Vortec' on top of it.)
 

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Discussion Starter #10
I apologize, when i first bought the engine I was told it was a 350 vortec. Upon looking around and running the casting numbers found out it's exactly what's in the article a 5.3 (which I guess is in the Ls family) I am running a carb on it, and getting the MSD ignition.

However, when it comes to the serpentine system, and the oil pan, I had a few questions.

1) was as stated, I'd rather not drop 400 dollars on a Holley oil pan if I do not need to.
Would I be able to buy an oil pan fitting the same engine that I have, but for a camaro, and not worry about hitting the cross member?

2) could use the 01 Tahoe power steer steering pump, and retrofit that into the skylark? If not, what power steering pump should I use, and will it mount to the stock serpentine system?

3) will I be able to run a stock 01 Tahoe alternator on the accessory drive, and if anyone had any information on how to wire a late model alternator to a classic gm

Once again I apologize for the confusion earlier, I was under the assumption that the engine I was buying was a vortec 350 however guess i have the one mentioned in the article
 

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I apologize, when i first bought the engine I was told it was a 350 vortec. Upon looking around and running the casting numbers found out it's exactly what's in the article a 5.3 (which I guess is in the Ls family) I am running a carb on it, and getting the MSD ignition.

However, when it comes to the serpentine system, and the oil pan, I had a few questions.

1) was as stated, I'd rather not drop 400 dollars on a Holley oil pan if I do not need to.
Would I be able to buy an oil pan fitting the same engine that I have, but for a camaro, and not worry about hitting the cross member?

2) could use the 01 Tahoe power steer steering pump, and retrofit that into the skylark? If not, what power steering pump should I use, and will it mount to the stock serpentine system?

3) will I be able to run a stock 01 Tahoe alternator on the accessory drive, and if anyone had any information on how to wire a late model alternator to a classic gm

Once again I apologize for the confusion earlier, I was under the assumption that the engine I was buying was a vortec 350 however guess i have the one mentioned in the article
Question 3 - Pirate4x4.Com - The largest off roading and 4x4 website in the world.

Read down the page a bit to find the wiring description. This link is for a CS130, but the lettering applies exactly the same (P L F/I S). It's reaaly pretty easy, you just need to identify the wires in your chassis.

Your swap isn't really all that difficult other than the fitment issues of the oil pan, trans mounting and motor mounts.

Best of luck - Jim
 
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