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L18 8.1L swap resource thread

Don't know what would make yours different than any other :dunno:
Come to think of it we yanked the 350 out of my old K5 to change the clutch since we didn't want to fuss with pulling the dump truck trans. Same as when we put the 350 into that one years earlier.
 
wow is she big!!!!!
got it in. notbolted down yet. had to pull trans and transfercase...

fan hits crossmember so had to bend blades. original owner i got engine from belt them so woulda needed a new one. elec fans i guess are required now...

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I've never seen an 8.1 where the fan hit that crossmember. The fan itself does not look like one for an 8.1.
 
wow is she big!!!!!
got it in. notbolted down yet. had to pull trans and transfercase...

fan hits crossmember so had to bend blades. original owner i got engine from belt them so woulda needed a new one. elec fans i guess are required now...

View attachment 359700
Some thing is wrong I'm running a Kodak fan and it has lots of room
I checked my fan and it is 19" and it is about 1" above the crossmember.
CB6E4A43-1922-44B7-A9EF-2346AF835867.jpeg

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supposedly 2002 silverado 2500hd extended cab
Looking at the GM parts catalog an 02 silverado would have a 9 blade fan not 5. ****Edit after Larry's post. The gm drawing shows 9, Larry's shows 5. The drawings I guess are not 100% accurate to go by.

The correct clutch will spin on with the large hub/but and not bolt to the fan pulley like the old stuff.
 
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wow is she big!!!!!
got it in. notbolted down yet. had to pull trans and transfercase...

fan hits crossmember so had to bend blades. original owner i got engine from belt them so woulda needed a new one. elec fans i guess are required now...

Well, I see a couple things….

First, the engine looks very low from the angle of your picture. It would be interesting to see what engine mounts/saddles are used along with the engine crossmember. The actual fan blade you’re using is fine as that is a truck/suv fan blade for an 8.1L. My bone stock 2001 Silverado has the exact same 5 blade fan. In all reality, it doesn’t matter which fan blade you use as long as it is a for a reverse rotation water pump with serpentine belt. The fan blades on my K10 and Suburban are from some old GMT400 with a 454. In fact, they look identical to what your using other than mine have more blades….like 7 or 9. Some oddball number

Second, you’re using pickup truck/suv accessory brackets that use a shorter water pump and crank pully vs. the high mount A/C type brackets most everyone else uses. That will cause the fan to be a tad closer to the engine than how we run them. If the engine is a bit too low combined with using a shorter waterpump could possibly be what is causing the fan to hit the crossmember.
 
supposedly 2002 silverado 2500hd extended cab
I confirmed your issue is with using the pickup truck water pump, crank pulley and accessories. Way back at the beginning of this thread on page 1 in Post #9 I mentioned the water pumps are different lengths as are the crank pulleys.

A quick look at reviewing Rock Auto part number specs shows the pickup truck water pump like you are using has a height of 5.95”. This pickup truck water pump is AC Delco 252732

The Workhorse/G-van/Medium Duty type bracketry is longer with a height of 7.25”. This water pump is part number AC Delco 251693

Here is a visual comparison of the Workhorse/G-van/Medium Duty crank pulley (on engine) compared next to a pickup truck pulley. The 1.25” difference in water pump length is why your fan is hitting the crossmember. The easiest thing for you to do is probably going electric fans or do some research to see if there are any other GM V8 spin on clutch fans with a longer shaft, which I kinda doubt exists that is that much longer. That said, your picture makes the engine look a tad bit on the low side but it may just be the camera angle but regardless that isn’t your main issue
50587932307_6d3622bd73_c.jpg
 
I confirmed your issue is with using the pickup truck water pump, crank pulley and accessories. Way back at the beginning of this thread on page 1 in Post #9 I mentioned the water pumps are different lengths as are the crank pulleys.

A quick look at reviewing Rock Auto part number specs shows the pickup truck water pump like you are using has a height of 5.95”. This pickup truck water pump is AC Delco 252732

The Workhorse/G-van/Medium Duty type bracketry is longer with a height of 7.25”. This water pump is part number AC Delco 251693

Here is a visual comparison of the Workhorse/G-van/Medium Duty crank pulley (on engine) compared next to a pickup truck pulley. The 1.25” difference in water pump length is why your fan is hitting the crossmember. The easiest thing for you to do is probably going electric fans or do some research to see if there are any other GM V8 spin on clutch fans with a longer shaft, which I kinda doubt exists that is that much longer. That said, your picture makes the engine look a tad bit on the low side but it may just be the camera angle but regardless that isn’t your main issue
50587932307_6d3622bd73_c.jpg

here are pics of my 02 and clearances. passenger side is awesome.. drivers side not so much...

and fyi... 454 manifolds

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here are pics of my 02 and clearances. passenger side is awesome.. drivers side not so much...

and fyi... 454 manifolds
Those look like 1996-2000 L29 454 manifolds. You can tell by the EGR tube at the driver’s side manifold. Like 8.1 manifolds, L29 manifolds were intended to go into a truck with a wider frame and don’t fit squarebody’s very well either without cutting into the frame. For some reason I suspect a guy that would install an engine that looks like it came straight out of the titanic would take issue with cutting into a frame. It may not hit now sitting static but it will once it is running. These manifold may also explain why you struggled getting the engine in :thinking:
 
Those look like 1996-2000 L29 454 manifolds. You can tell by the EGR tube at the driver’s side manifold. Like 8.1 manifolds, L29 manifolds were intended to go into a truck with a wider frame and don’t fit squarebody’s very well either without cutting into the frame. For some reason I suspect a guy that would install an engine that looks like it came straight out of the titanic would take issue with cutting into a frame. It may not hit now sitting static but it will once it is running. These manifold may also explain why you struggled getting the engine in :thinking:
so replace manifolds. thought any 454 would work. got a better suggestion what I should look for?
 
For some reason I suspect a guy that would install an engine that looks like it came straight out of the titanic would take issue with cutting into a frame. :thinking:

lol.. and i know it looks rough. my plan is to install.. get all bugs wotked out..wiring..etc..
then in a year or 2 pull it. all new water pump..ps pump.. sand paint brackets and rebuild..paint engine. it will be a poloshed titanic engine when im done.
 
so replace manifolds. thought any 454 would work. got a better suggestion what I should look for?

Yes, the obvious manifolds to use would be those of a squarebody with a big block :dunno: . There is nothing special about the 8.1 than any other BBC when it comes to exhaust manifolds or headers as I wrote on page 1
 
Yes, the obvious manifolds to use would be those of a squarebody with a big block :dunno: . There is nothing special about the 8.1 than any other BBC when it comes to exhaust manifolds or headers as I wrote on page 1

no one said im the sharpest at this lol. im a computer tech...

anyway.. ill get squarebody headers then.

also figured out fan hitting member.. another not the brightest moment... i dont normally pull engines. bolt on back was too long and hit cab. was keeping engine up. sawzall ald when it cut.. entire engine dropped more than a half inch...
was either cut and remove with pliers or yank engine...

lessons learned for when we do 5.3L in my sons nissan 350z and twin turboing..
 
Everything fits nicely with the pickup water pump/fan. I'm even using the fan shoud/intake elbow and rad with minor modification. I'll be trying to source the hard to find workhorse brackets once I'm ready for ac.

I was wondering about that because it seems like we would have heard of this fan hitting the crossmember before. Plus, when I looked at mine, it appeared there would still be plenty of room even if the fan was 1.25” closer to the engine
 
lookin good. your near me.. i need to see this beast and maybe ride shotgun to feel the power i can expect!!!!!
I felt the power for about 10 miles last I towed the k5 I thought it was gonna rip the lugs of the boggers but then the nasty miss-communication of 4-5 cylinders reared its ugly head ergo the complete truck side rewire just to reassure I don't have a corrupt ground or low voltage issue at high rpm. I haven't found anything evident other than it was ugly. Troy at Howell sent out a new ecm to swap in in case the one they sent was compromised. I'm apprehensive but very appreciative
 
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