82 GMC sierra C15 Inline 6 to 454 swap?

[dkcortines]

I currently have a 2wd long wheel base gmc sierra with an inline 6 that has seen better days. I am on the fence of what to do. Swap to the 454 sounds appealing but do not want to get into heavy mods like fabrication cutting firewall etc. I understand upgrades like front suspension, cooling system, and motor mounts need to be purchased that’s fine. I want use this truck as a farm truck around my place that has plenty of power to do what I need and be fun to drive around doesn’t need to win at the drag strip. Eventually will be swapping trans and making 4x4 but doing in stages by myself and kids having fun with it. Could anybody give advice to what mods are necessary to swap from an inline 6 to 454 is it bolt in? Would I have to move steering? Would headers be a problem in this chassis. I could also easily go the 350 route and I know it would be a lot less involved but wanted to see what the 454 would involve as a swap.

Any help appreciated thanks in advance

 

[bucket]

A 350 swap is the same amount of work as a 454 swap. Either way, you have to swap mounts to v8 mounts.

 

[DoubleDingo]

Which i6?

 

[dkcortines]

Sorry it is the 4.1L 250 I6

 

[75gmck25]

The 454 was a factory option, so no special mods needed to fit it in your truck. You do need a cooling system and transmission that is up to the job, and probably need to upgrade the front springs.

In my opinion, building and swapping in a 454 is often not worth the trouble unless you just want bragging rights because you have a big engine. Most parts are more expensive than an SBC when you are building for performance, so if you are on a budget you might end up with a relatively stock 454 that does not perform any better than a performance-oriented 350. YMMV

 

[Trucksareforwork]

At this point I kinda want an I6 truck. That’s where the bragging rights are. Everybody has a 400 hp v8.

 

[Craig Nedrow]

I swapped my broke 350 for my circle track 350. I to am a farmer/rancher, and hauled hay to customers. The 350 did ok, but I found a Mark lV 454, and never looked back. The 454 get slightly less mileage than the 350, but the torque and power, I’m hooked, and if you tow, no comparison between the two.

 

[bucket]

The 454 was a factory option, so no special mods needed to fit it in your truck. You do need a cooling system and transmission that is up to the job, and probably need to upgrade the front springs.

In my opinion, building and swapping in a 454 is often not worth the trouble unless you just want bragging rights because you have a big engine. Most parts are more expensive than an SBC when you are building for performance, so if you are on a budget you might end up with a relatively stock 454 that does not perform any better than a performance-oriented 350. YMMV

Springs aren't an issue, especially starting with an I6. Iirc, they are heavier than a small block.

A 454 makes torque. Torque is fun. But if they fall out of favor for small blocks, I'm OK with that. More 454's for me

 

[Ricko1966]

Hi.

Springs aren't an issue, especially starting with an I6. Iirc, they are heavier than a small block.

A 454 makes torque. Torque is fun. But if they fall out of favor for small blocks, I'm OK with that. More 454's for me

Did you ever notice nobody pulls the 454s out of there motorhomes to swap in these bad boy 5.3s and 350s?

 

[75gmck25]

I will add to my comments. One very good reason to choose a 454 is if you are towing, or hauling a heavy load that requires a lot of low end torque. You can get good horsepower out of an SBC, but for torque you can’t beat what you get out of BB displacement.

 

[mcarlo86]

Springs aren't an issue, especially starting with an I6. Iirc, they are heavier than a small block.

A 454 makes torque. Torque is fun. But if they fall out of favor for small blocks, I'm OK with that. More 454's for me

A 250 6 cylinder is about 450 pounds, so lighter than a small block V8. The old 235 6 cylinders where the ones that were over 600 lbs.

 

[VikingMech]

I just finished putting a Gen VI 454 in mine. There's plenty of room in the engine bay, firewall clearance, steering, etc. I used Chevelle headers but had to modify one tube on the driver's side to clear the frame. BBC stock manifolds would probably be better. Summit BBC oil pan did not clear my 4x4 front crossmember. Maybe a stock pan would clear, but I did a bolt-in high clearance crossmember from Offroad Design. Not sure what you want to use for a trans, but a 4L80e is longer so the trans crossmember needs to move back a bit. Water pump and fan sit further forward so the smallblock fan shroud may not work. Aside from those couple things it was pretty easy and works well.

 

[Craig Nedrow]

I just finished putting a Gen VI 454 in mine. There's plenty of room in the engine bay, firewall clearance, steering, etc. I used Chevelle headers but had to modify one tube on the driver's side to clear the frame. BBC stock manifolds would probably be better. Summit BBC oil pan did not clear my 4x4 front crossmember. Maybe a stock pan would clear, but I did a bolt-in high clearance crossmember from Offroad Design. Not sure what you want to use for a trans, but a 4L80e is longer so the trans crossmember needs to move back a bit. Water pump and fan sit further forward so the smallblock fan shroud may not work. Aside from those couple things it was pretty easy and works well.

Man that’s clean good install brother