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-   -   Should I change the size of engine (https://www.gmforum.com/oldsmobile-171/should-i-change-size-engine-311533/)

Mattyhewson25 Jan 10, 2018 06:56 PM

Yeah, that was my mistake the motor is a 3.4l v6 not 2.4 sorry bout that.

Mattyhewson25 Jan 10, 2018 10:16 PM

But yeah I would like to replace the current engine with something that I can easily find parts for, and still add mods to the motor.

CathedralCub Jan 12, 2018 01:57 AM


Originally Posted by Mattyhewson25 (Post 1625377)
But yeah I would like to replace the current engine with something that I can easily find parts for, and still add mods to the motor.

I guess that comes down to:

- how much work you want to do
- your skill level doing it
- how much downtime you can afford for your car to have for the swap
- how much downtime you can afford later while you sort out the quirks
- how much money you want to throw at it (whatever number you have after careful planning should be tripled, unless all of your donor parts are going to be completely overhauled)

This isn't a simple swap. Are there more complicated ones? Yes, but this isn't like swapping a 327 for a 350 in a square-body pickup. From what I can tell you are one timing cover, a couple of belts, I suggest an alternator, and some odds and ends away from having a pretty good car back running reliably again.

Either way: we'll help where we can and are interested in how this comes out. :)

CathedralCub Jan 12, 2018 01:58 AM


Originally Posted by Mattyhewson25 (Post 1625374)
Yeah, that was my mistake the motor is a 3.4l v6 not 2.4 sorry bout that.

No problem. If we didn't have typos then the spell-check bots would get bored, start Skynet, and take over the world with lasers and Austrian accents.

Mattyhewson25 Apr 6, 2018 01:30 AM

So a couple weeks ago one of my friends told me to have the heads checked for any damage. So following his advice I dropped of the motor at a local repair shop to have the heads inspected and got the news that they had damage. However I do now of were I can get my hand on 1995 regal (same body frame and transmission) with only around 25,000 more miles on it and in need of a new head gasket. It is a 3800L. I do have time and a little money with a little nowhow.

rjolly87 Apr 6, 2018 10:09 AM

I would be concern with any 3800 needing a head gasket, because they typically don't fail.

If you are going to swap, it may be fun to look at a 96 Regal, those had series 2 engines, good for over 200hp��

Mike Apr 6, 2018 12:30 PM


Originally Posted by rjolly87 (Post 1626496)
I would be concern with any 3800 needing a head gasket, because they typically don't fail.

If you are going to swap, it may be fun to look at a 96 Regal, those had series 2 engines, good for over 200hp��

Agreed, 3800 head gaskets don't fail, unless you over heat them.

Mattyhewson25 Apr 6, 2018 05:01 PM

Yeah it did overheat because the coolant ran low. So.... Can one rebuild the motor??

rjolly87 Apr 6, 2018 07:02 PM

Rebuilding can be hit or miss with these engines, and they very rarely have the same magic they did factory built. Given that it is equally possible there may be a cracked head too.

Best bet is typically finding a used motor in that scenario. The donor could get you one block away from the 3.8 swap I suspect however.

CathedralCub Apr 9, 2018 04:02 PM


Originally Posted by rjolly87 (Post 1626496)
I would be concern with any 3800 needing a head gasket, because they typically don't fail.


Originally Posted by Mike (Post 1626500)
Agreed, 3800 head gaskets don't fail, unless you over heat them.

I'll pile on: Yeah, 3800 head gaskets don't tend to fail. Extremely-terrible things have happened to that engine to allow a blown head gasket. Even had mine scary-low on coolant a couple of times when the infamous EGR-passage issue was starting and I didn't realize. Swapped the upper intake manifold at around 145,000 miles and it's been good since. It turned 220,000 on Saturday in my driveway with the factory head gaskets.

So now you'd have a 3800 that had been really hot, now you need to worry about warped heads and possible scored and rusted cylinder walls (from coolant entering cylinders, maybe contaminated oil (from coolant bleeding past pistons into crankcase, etc. etc.

You'd be better off finding any other 3800 in a junkyard, checking for even compression, and calling it good.


Originally Posted by Mattyhewson25 (Post 1626494)
heads inspected and got the news that they had damage

What kind of damage?


Originally Posted by Mattyhewson25 (Post 1626494)
I do have time and a little money with a little nowhow.

I don't like quoting myself, but these questions will really help:


Originally Posted by CathedralCub (Post 1625392)
- how much work you want to do
- your skill level doing it
- how much downtime you can afford for your car to have for the swap
- how much downtime you can afford later while you sort out the quirks
- how much money you want to throw at it (whatever number you have after careful planning should be tripled, unless all of your donor parts are going to be completely overhauled)

I'd also suggest (regardless of the particular 3800 you use) that you put together a plan and estimate how much time each necessary step will take. For example: The alternator is in a different place, what will it take to wire properly, and how much time and money will be involved. Same with power steering, air conditioning, PCM, etc.

Is the current transaxle in good shape? Would sure hate to have not asked then have it fail on you two weeks after completion with a more-powerful and torquier engine on top of it.

Not trying to discourage. It's just I've seen several of these end up in a junkyard halfway done because there are so many surprise details.


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