Is the 8.1 still a dead end swap?

[Frankenchevy]

I was talking to a buddy about the swap and mentioned to him my concerns about the weight of the engine since I have ORD custom springs. He seems to think the 8.1 is very heavy. I’m trying to find an exact weight to compare against a small block.

 

[77 K20]

It was believed to be a bit over 750 lbs for the 8.1

 

[Frankenchevy]

It was believed to be a bit over 750 lbs for the 8.1

That’s what I’ve seen…and a small block weighs about 500, I guess. I’ll have to call ORD to see if that’s enough to matter. I might be switching to Deavers sooner than I thought.

 

[BearKing]

Before you go disassembling that Suburban, if it's in good shape and not thrashed you can get about $11-12K for it. No I'm not on drugs, especially if it has 4.10 gears and no rust. My suburban is almost identical see below. I'm on a 2500 Suburban form and this a realistic price. People are looking for these constantly.

If you choose to remove the engine let me know, I need a couple of trim pieces.

My '01 2500 8.1L

You must be registered for see images attach

This guy on You Tube put an 8.1 into a Square body Suburban.
Pete's Place
https://www.youtube.com/c/PetesPlaceGarage

PSI bought the 8.1 from GM, they have different brackets for truck and bus use. Many U-hauls and Schwann's trucks ran 8.1L engines too.

Raylar Performance can build a 8.1L motor for you, but I would guess that would cost $10K +.

You must be registered for see images attach

I agree with this and just and FYI, we call the 8.1 2500 Suburbans….UNICORNS for a reason. That’s what all the truck guys call them anyway. Have for many years now. They sure are Unicorns in the truck world. Hard to find for sure.

 

[K10eddie]

I've actually been thinking about doing this myself in my 1984 C20. 4L80E with a controller, and a carb setup for the 8.1.

Richard Holdener has recently done videos on an 8.1 for dyno work with mild bolt ons and even one with a turbo. I think with just an intake and tune it made about 425hp/500tq~ iirc. They're heavy engines, but the torque kicks in so quick, I doubt most people will notice. He even has a dyno video with a turbo, and it make like 600hp/800tq on only 6-7psi. It's been a while since I watched the videos, but I think that's what it did.

xc_hide_links_from_guests_guests_error_hide_media

 

[Frankenchevy]

They're heavy engines, but the torque kicks in so quick, I doubt most people will notice.

The weight issue for me pertains to my springs. The front springs were around $1000 and are built specifically for my current setup with a small block. They’re extremely soft compared to my factory k30 springs spec’d for a 6.2. I’m sure I’ll lose some lift with an 8.1/4l80 over a 5.7/nv4500.

Either way, I’ll likely get the burb. Might just flip it, might part it out…not entirely sure at this point. It might be a pile underneath the body. I’ll find out tomorrow.

 

[Bextreme04]

The weight issue for me pertains to my springs. The front springs were around $1000 and are built specifically for my current setup with a small block. They’re extremely soft compared to my factory k30 springs spec’d for a 6.2. I’m sure I’ll lose some lift with an 8.1/4l80 over a 5.7/nv4500.

Either way, I’ll likely get the burb. Might just flip it, might part it out…not entirely sure at this point. It might be a pile underneath the body. I’ll find out tomorrow.

A fully dressed 350 is about 575lbs. A fully dressed 8.1L is about 761 lbs. So... less than 200lb difference. If you want to see how much difference it will make on the springs to swap the motor, just put a few bags of cement in the engine compartment and drive around. I bet you wont even really notice. Even more, an NV4500 weights MORE than a 4L80e. NV4500 is about 195lbs, while a 4L80E is only 175 lbs. So total difference in weight between a 350/NV4500 and an 8.1/4L80e is only 166lbs... which is less than most passengers are going to weigh. One bag of cement on each inner fender would tell you exactly what that is going to feel like and do to the springs.

 

[yevgenievich]

I would buy that one and keep as is if it was closer

 

[Frankenchevy]

Forgot to close this out. The person selling it let me know it was an auction car, mentioned it has a miss (which may just be plugs) and it also had weight going against it with respect to my springs. At 178,000 miles I’d be more likely to take a chance if the history was known, but …I passed.

The price was in the same ballpark as a new 383 from Blueprint. An aluminum headed small block will fit much better with my current suspension and plans for the truck.