GRAND PRIX Possible 3.8 V6 Replacement

[565bbchevy]

With machine shops being few and far between now, overhauling an engine would not be cost effective. My budget is limited, .

The problem when it is suggested to go with a Buick 350 is while it is a direct swap you first have to find one that is still in good running condition and since they have not been in production in nearly 30 years and depending where you live finding one might not even be possible and if you find one that is not running and you want to use it you are at the mercy of some machine shop that you have never dealt with before to go through it.
So the reality is since money is an object for you I would just work with the 3.8 you already have but if you decide to spend the money and want affordable power that is where a SBC makes sense, it is available new from GM with a factory warranty or rebuilt by many aftermarket vendors with a warranty and parts are inexpensive and available everywhere.
While I have nothing against a Buick 350 swap it typically is not a budget minded swap by any means.

 

[43grandprix]

Easiest thing to drop in is a BUICK 350 and a short shaft Th350 transmission.
I've done it twice. 3.8/4.1 out, 350 Buick in. Same wires, mounts, starter, everything. 455 fits as well, with some minor engine mount mods.
You can use the front accessory brackets off the 3.8/4.1 on the 350 as well.

if money is no object and you want to be like everyone and their grandma, go SBC. I'd go a pontiac 400 myself in a GP.

Am glad to know that you can use the same wires, mounts, starter etc. if you use a Buick 350! Am afraid money is limited, so I need to do the most cost effective way of making my Grand Prix reliable, as I plan on keeping it forever! Also glad to know that the front accessory brackets from my 3.8 will work on there as well!

 

[43grandprix]

The problem when it is suggested to go with a Buick 350 is while it is a direct swap you first have to find one that is still in good running condition and since they have not been in production in nearly 30 years and depending where you live finding one might not even be possible and if you find one that is not running and you want to use it you are at the mercy of some machine shop that you have never dealt with before to go through it.
So the reality is since money is an object for you I would just work with the 3.8 you already have but if you decide to spend the money and want affordable power that is where a SBC makes sense, it is available new from GM with a factory warranty or rebuilt by many aftermarket vendors with a warranty and parts are inexpensive and available everywhere.
While I have nothing against a Buick 350 swap it typically is not a budget minded swap by any means.

Thanks for telling me about the Buick 350. I definitely need to be budget minded. All I'm concerned about is the reliability of the engine and have a bit more power than the current 3.8 V6. My concern with the current 3.8 is how many miles does it really have on it and of course you don't know if it's on its last legs or not. It doesn't knock, has good oil pressure (the oil pressure gauge says about 40 lbs.going down the road and about 20 at idle) and seems to run ok. Someone here suggested that I think of installing EFI. How much would that cost? The car has a DualJet carb on now and sometimes it's given me fits.

 

[43grandprix]

You might be able to find a good running donor car that you can take the drivetrain out of but both Jegs and Summit sell GM crate engines and far as brackets you could possibly find them locally and get everything or post in the wanted section on here if you decide to go this route.
Many people are swapping from SBC to LS so they might part out their brackets cheap.
There is also a GM serpentine kit that includes everything for just over $900, you can see how quickly money goes into this swap when you are starting from scratch.

You mentioned that people are swapping from SBC to LS. What is an LS engine? What is the advantage of it over a small block Chevy? The serpentine kit sure is expensive!

 

[565bbchevy]

It sounds like your engine is in good running order, as far as EFI while they are far more affordable than they were years ago you will still probably spend between $1200 and $1500 to get the system going. Fitech has this unit that is good up to 400 horse so if you change your mind about the V6 you can transfer it over to a healthy V8.
https://www.summitracing.com/parts/fif-30003/overview/
Keep in mind you still need a fuel system and a Gbody FI tank but you will end up with a great running car that starts up and drives good cold and remote start would even be an option later if you wanted.

 

[MrSony]

The thing about the 350 Buick, yes. They are scarce. Only made for 12 years, 68-80. If you can find one, you WILL need to rebuild the oil pump (or buy a new timing cover, all assembled, tested, and blueprinted for 190 bucks), and replace the front cam bearing with a hardened dual groove one. Comp 268 cam, valve job on the heads, if you take it to the bare block, the 340p pistons from summit will give you 9.3:1 with stock deck height. Or a crower level 4 cam retarded 4* would work great. Headers, take em or leave em. 30hp gain isn't worth 500 bucks. 350 buick manifolds flow REALLY well for what they are. you can look in the inlet and out the downspout. Where are you located? Check craigslist. Or Facebook, if you have that.

 

[bob64]

"advice" "budget" if the Engine runs good keep it. You want Duals then install duals with an open mind that you will upgrade the Engine/driveline down the road.

No matter what you choose to do if your going to keep the car you'll always be changing some part of it along its life span. It's just a fact of life.

Don't get in a rush! Take your time or things can get costly. Search out parts that are up-grades.

Also remember that if or when you change the Engine that the rest of the car will need to handle that power.

Building a car is like a puzzle, everything has to fit just right an some sit and put it together in a day and some take years to get that perfect picture. It's up to you how much coin and how you wish the end result to be!

 

[43grandprix]

It sounds like your engine is in good running order, as far as EFI while they are far more affordable than they were years ago you will still probably spend between $1200 and $1500 to get the system going. Fitech has this unit that is good up to 400 horse so if you change your mind about the V6 you can transfer it over to a healthy V8.
https://www.summitracing.com/parts/fif-30003/overview/
Keep in mind you still need a fuel system and a Gbody FI tank but you will end up with a great running car that starts up and drives good cold and remote start would even be an option later if you wanted.

Thanks for the suggestions on the EFI. Am glad to hear that my current engine is ok for now, but I still need to get a compression test done. Am unable to do it myself as I have a bad back and don't have a compression gauge. Is there an EFI kit that includes the FI tank and other parts for the fuel system?

 

[43grandprix]

"advice" "budget" if the Engine runs good keep it. You want Duals then install duals with an open mind that you will upgrade the Engine/driveline down the road.

No matter what you choose to do if your going to keep the car you'll always be changing some part of it along its life span. It's just a fact of life.

Don't get in a rush! Take your time or things can get costly. Search out parts that are up-grades.

Also remember that if or when you change the Engine that the rest of the car will need to handle that power.

Building a car is like a puzzle, everything has to fit just right an some sit and put it together in a day and some take years to get that perfect picture. It's up to you how much coin and how you wish the end result to be!

Right now the engine does run good and hasn't given me much trouble. I had the water pump and radiator replaced. The rear main seal had leaked when I bought the car in 2005 and the repair shop found that the crank bearings were worn and they were replaced as well. Thank goodness the crank was ok! Yes, I realize that if I get the engine changed to a V8, that the automatic transmission and/or rear end will also need replaced. I want the car to look like Richard Petty's G-Body Grand Prix, but the interior to stay factory looking. I don't want a complete modification as it would be too much money. Have body work to do before the drivetrain is worked on. Thanks.

 

[43grandprix]

It sounds like your engine is in good running order, as far as EFI while they are far more affordable than they were years ago you will still probably spend between $1200 and $1500 to get the system going. Fitech has this unit that is good up to 400 horse so if you change your mind about the V6 you can transfer it over to a healthy V8.
https://www.summitracing.com/parts/fif-30003/overview/
Keep in mind you still need a fuel system and a Gbody FI tank but you will end up with a great running car that starts up and drives good cold and remote start would even be an option later if you wanted.

The thing I'm kind of worried about right now is what should I do about the torque converter seal leak. It isn't leaking real bad yet. Was told it would cost about $500 to replace the seal! Am not sure which automatic transmission is in my GP. Could it be the TH200? Have read on here that that model isn't a good one. What would you do if you were in my shoes? Get the seal replaced or replace the transmission with something better? Am worried about the DualJet carb as well. Both choke pull-offs have been replaced, but it's never been cleaned or overhauled since I've owned the car. Gas where the car is unfortunately has some ethanol in it so I need to put that into consideration of what to do! Right now I desperately need to get the window sweeps replaced and power window motor replaced on the driver's door, as the window doesn't want to move unless you bang on the door panel! Also need to get the dash light sockets replaced as some of them flicker (had all the bulbs replaced years ago, but they may have failed again) and speedo cable R&R before the dash panel is put back on (has been off for 12 years WAITING FOR ME to get going on it! YIKES!!)