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L18 8.1L swap resource thread

Larry said:
The whole intake bolt thing does get confusing and the sad thing is, the longer bolts didn’t do a whole lot to address oil consumption anyway.

If your heads have the blind intake bolt holes and you’re using the long bolts I suspect they will probably start snapping off as you torque the bolts down. That is what happen to the 8.1L as I was assembling it for the Suburban.[/QUOTE
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This does stick out farther than I realized. Shown with a used gasket.
Hey @Larry while we are on the subject, throw the end gaskets in the trash and use
The Right Stuff like older Chevys?

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Larry said:
The whole intake bolt thing does get confusing and the sad thing is, the longer bolts didn’t do a whole lot to address oil consumption anyway.

If your heads have the blind intake bolt holes and you’re using the long bolts I suspect they will probably start snapping off as you torque the bolts down. That is what happen to the 8.1L as I was assembling it for the Suburban.
Click to expand...

So what needs to be done to the engines that had the oil consumption problem? I bought one a while back that was pulled out at 3000 miles and has set in storage ever since. I think it is a 2003 model.
 
Capt Ron said:
This does stick out farther than I realized. Shown with a used gasket.
Hey @Larry while we are on the subject, throw the end gaskets in the trash and use
The Right Stuff like older Chevys?
Click to expand...
I’ve never really looked at them at that angle. I’d say as long as the head has an opening for that chunk to fit in to you’d be fine. Actually, I do use the end gaskets on L29s and 8.1L’s as the new style intake gaskets are so much better than the old school ones but I do use GM 12378521 RTV in the corners. RightStuff should work fine too, its just a sumbish to get off later.
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rksjd8420 said:
So what needs to be done to the engines that had the oil consumption problem? I bought one a while back that was pulled out at 3000 miles and has set in storage ever since. I think it is a 2003 model.
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Keep putting oil it it :dunno:. Plan on adding quart every 1000 miles as that is what the service manual spec is for the 8.1. Most exceed that some don’t. My bone stock 8.1L in my 2001 Silverado has used a quart of oil every 1,200 miles like clock-work from the day I drove it off the lot when it was brand new. It had those oil consumption bulletin fixes done while in warranty and did not change anything. On the other hand, the 8.1L in my K10 burns a qt about every 2K and the Suburban doesn’t use any between oil changes but it is the newest model year engine of all of them (2008). Some people on the various 8.1L Facebook group claim they have added an oil catch and created a true PCV system and helped with oil consumption. I’m not interested in following some of those guys barnyard "fixes" so I just keep oil handy
 
Larry said:
I’ve never really looked at them at that angle. I’d say as long as the head has an opening for that chunk to fit in to you’d be fine. Actually, I do use the end gaskets on L29s and 8.1L’s as the new style intake gaskets are so much better than the old school ones but I do use GM 12378521 RTV in the corners. RightStuff should work fine too, its just a sumbish to get off later.
49322844388_3c077f9726_z.jpg






Keep putting oil it it :dunno:. Plan on adding quart every 1000 miles as that is what the service manual spec is for the 8.1. Most exceed that some don’t. My bone stock 8.1L in my 2001 Silverado has used a quart of oil every 1,200 miles like clock-work from the day I drove it off the lot when it was brand new. It had those oil consumption bulletin fixes done while in warranty and did not change anything. On the other hand, the 8.1L in my K10 burns a qt about every 2K and the Suburban doesn’t use any between oil changes but it is the newest model year engine of all of them (2008). Some people on the various 8.1L Facebook group claim they have added an oil catch and created a true PCV system and helped with oil consumption. I’m not interested in following some of those guys barnyard "fixes" so I just keep oil handy
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Thanks. That was my plan. I haven't seen anything that made much sense on GM's recommended "fixes". I trust your advise more than GM's.
 
Received my order with the water pump bolts in it - No joy. Those bolts are too short. I'll probably just measure the one that fits and order a standard bolt the same size. There is no listing for water pump bolts anywhere online. I suppose I could try my local dealership, but they are usually super expensive and won't give out part numbers.
 
Russell said:
Received my order with the water pump bolts in it - No joy. Those bolts are too short. I'll probably just measure the one that fits and order a standard bolt the same size. There is no listing for water pump bolts anywhere online. I suppose I could try my local dealership, but they are usually super expensive and won't give out part numbers.
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Here are the water pump bolt choices. Its basically two part numbers on this list, which the last bolt part number came from the Workhorse EPC. 11516361 or 11516109

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RootBreaker said:
so... I have the AC on the passenger side. What do I need for the AC delete?
I see this but a comment was that it was too close to the steering pump, thus that is the drivers side???
https://www.summitracing.com/parts/rnb-34175/reviews/
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If you have a pickup truck bracket with A/C on the passenger’s side all you need to do is remove the compressor and belt just like an LS engine (the compressor runs on its own belt). That’s it! Ez peezy....nothing to buy
9035347629_0ae200d4a8_z.jpg



Now if you had a Workhorse/G-van/Medium Duty type bracket and wanted to delete A/C, just add an idler and shorter belt
9035352923_1266b22bd2_z.jpg
 
Larry said:
If you have a pickup truck bracket with A/C on the passenger’s side all you need to do is remove the compressor and belt just like an LS engine (the compressor runs on its own belt). That’s it! Ez peezy....nothing to buy
9035347629_0ae200d4a8_z.jpg



Now if you had a Workhorse/G-van/Medium Duty type bracket and wanted to delete A/C, just add an idler and shorter belt
9035352923_1266b22bd2_z.jpg
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out of a 2001 Silverado 3500...
 
Anyone have dimensions of the oil pan such that I could build a wooden holder for transport?
 
I have to say, what a amazing thread this is.

After going back and forth on what I was going to do to my 87 6.2/400/208 V20 Burb. I made a decision and joined the 8.1 club in November. Since then, I have been amassing parts and collecting as much info as I can. I’m not sure if there hasn’t been a question that popped up in my head that hasn’t been answered here.

I actually wasn’t even considering a 8.1 until I reached out to a friend that owns a fab and motor company in Gilroy Ca. I had picked up a 6.0 ls and was on the hunt for some good used parts. After a few conversations and months of hustling, I picked up my Tilden Motorsports 8.1!

I originally was going to put a tbi454 in, then a 6.0 ls. But I really wanted the BBC. I got the best of both worlds.

42A0CC87-655C-4E57-A04F-04E5AA5B126B.jpeg
 
Anybody have a good site to look up exploded diagrams and part numbers?

Right now I'm looking for the gaskets that go at the ends of the giant iron coolant crossover tube and can't find them listed anywhere.
 
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