Leave it. It works fine and it'll be covered by the carpet on the interior.
Higher horses, higher revs & even higher torque, a streetable LJ engine swap
- Thread starter toximus
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B00mb00m
The Church of Cutting Brakes of Atlas-Front Digs
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Before welding up the transmission mount I finalized the location of the new drivetrain by moving the engine where it fits (there's about a 1/2" window for it), and then angling the rear output of the transfer case to point at the yoke on the rear axle. I did this by running string between the yokes (both at the same orientation) and an angle to check. I placed a laser at the front and back of the Jeep to mark the true center of the Jeep. The engine ended up somewhere around 3/4" offset in the front, and 3/8" offset at the rear of the transfer case — my measurements will obviously be different than another Jeep based on which components it's running and even wheelbase.
I then set off to make my cardboard transmission mount into reality.
Everything is made out of .120" or 1/8". The crossmember is 1-1/4" DOM.
The hex head bolts wouldn't fit in the 1x1 tubing with a socket so I welded a button head on and placed an order for some new bolts.
I found there's a 1* discrepancy between level on my engine and the adapter from Advance Adapters. I decided to focus on leveling the engine since the Atlas doesn't care which orientation it's in.
When I made the bushing assembly I used as tight of tolerances as possible. I found that this placed the Atlas about 3/16" lower than I would have liked. So I made a shim to raise it to the desired height.
I still need to place a gusset on the center support to the crossmember. That'll happen during final welding. As well as attaching the crossmember to the frame <— that will happen after getting the engine mounts in place. For now, the ends of the DOM are cut at a 9* angle and sit close to the frame so I have length to work with later.
Everything is made out of .120" or 1/8". The crossmember is 1-1/4" DOM.
The hex head bolts wouldn't fit in the 1x1 tubing with a socket so I welded a button head on and placed an order for some new bolts.
I found there's a 1* discrepancy between level on my engine and the adapter from Advance Adapters. I decided to focus on leveling the engine since the Atlas doesn't care which orientation it's in.
When I made the bushing assembly I used as tight of tolerances as possible. I found that this placed the Atlas about 3/16" lower than I would have liked. So I made a shim to raise it to the desired height.
I still need to place a gusset on the center support to the crossmember. That'll happen during final welding. As well as attaching the crossmember to the frame <— that will happen after getting the engine mounts in place. For now, the ends of the DOM are cut at a 9* angle and sit close to the frame so I have length to work with later.
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I shot a laser at the crank to show how low the engine is sitting on the frame. This is around 1-2" lower than the inline 6 sat.
Here's a first look at the intake sitting on the engine.
I haven't heard anything about when the correct alternator brackets are expected to ship so excuse the sloppy mock up here. I'll go into my ideology behind moving the alternator and list out in depth the details once I have that all in hand.
I talked with Drew at Goatbuilt about their accessory drive brackets. He's sending me out updated standoffs which will correct the issue I'm having with the bracket hitting the water pump. He also mentioned that some guys have reported the belt gets thrown with this belt routing and they narrowed the issue down to the Gates TJ tensioners. They switched to Dayco tensioners and haven't had an issue with it since. He said if the belt is going to be thrown it happens right away — not as a surprise down the road.
I'll keep an extra belt onboard just in case and worst case I'll revert back to both the alternator and power steering pump on the driver side which doesn't have any issues and will be easy enough to switch on a weekend even after the swap is completed.
Here's a first look at the intake sitting on the engine.
I haven't heard anything about when the correct alternator brackets are expected to ship so excuse the sloppy mock up here. I'll go into my ideology behind moving the alternator and list out in depth the details once I have that all in hand.
I talked with Drew at Goatbuilt about their accessory drive brackets. He's sending me out updated standoffs which will correct the issue I'm having with the bracket hitting the water pump. He also mentioned that some guys have reported the belt gets thrown with this belt routing and they narrowed the issue down to the Gates TJ tensioners. They switched to Dayco tensioners and haven't had an issue with it since. He said if the belt is going to be thrown it happens right away — not as a surprise down the road.
I'll keep an extra belt onboard just in case and worst case I'll revert back to both the alternator and power steering pump on the driver side which doesn't have any issues and will be easy enough to switch on a weekend even after the swap is completed.
The transmission crossmember really firmed up the rest of the driveline placement and it no longer moves when I bump it. So I moved the engine back to it's home and cycled the front axle to check again for clearance.
Everything cleared the 1-1/4" driveshaft except for a few tiny spots I won't know for sure until after my real driveshaft is in place:
This picture at full articulation shows how far under the oil pan the axle travels:
Everything cleared the 1-1/4" driveshaft except for a few tiny spots I won't know for sure until after my real driveshaft is in place:
- The corner of the Savvy mid-arm mount on the frame may barely kiss the driveshaft (easily fixable).
- The knobs that stick out the oil pan may get close to the larger splined section of the driveshaft (I'm going to cut those off anyway).
- Where the cable attaches to the 6L80e shift lever rubs under articulation when the transmission is in park, neutral, reverse and maybe a little bit in drive (didn't hit in tap shift position). This may prevent being able to shift while in extreme articulation situations. Although even in a nose over situation where I want to quickly shift from drive (or tap position) to reverse I can't imagine that the front end would be articulated like that. So I don't think this will ever be a problem aside from not being able to put it in park for poser shots.
This picture at full articulation shows how far under the oil pan the axle travels:
I got off work at 1, and Mrs Tox treated me to a variety pack of beef jerky and monster at 4. Let's get this holiday build fest started!
To get more room on the passenger side I swapped the CTS-V manifold back to the one that came with the engine.
Started mocking up the engine side mount:
The mockup for the frame side bracket is starting to take rough shape.
anything here you could copy or take ideas from.
https://davescustomsunlimited.com/products/ls1-gen-iii-engine-conversion-components-1/
you'd be surprised what ends up in the scrap bin next to the laser at work. if you need tabs or gussets lemme know.
maybe i missed it, were'd you pick up those bushings used in the trans mount? rubber or urethane?
https://davescustomsunlimited.com/products/ls1-gen-iii-engine-conversion-components-1/
you'd be surprised what ends up in the scrap bin next to the laser at work. if you need tabs or gussets lemme know.
maybe i missed it, were'd you pick up those bushings used in the trans mount? rubber or urethane?
Thanks for the offer. Tabs and gussets are always useful and save considerable time vs making. I took a peek at what's available online before starting but I didn't notice any premade tabs this size in 1/8". I'll hit you up the next time I need some tabs.
Dave's and Genright both appear to be placing their TJ LS brackets right in the path of my UCA.
Do you have the capability to cut 3/8" 6061-T6 brackets and spacers to precise length? I'm considering converting the engine accessory brackets from steel into aluminum. I could even send you the brackets so they'd measure up perfectly.
as precise as a tape measure and a shop band saw would allow. i do have some 3/8" 6061 (rough mill finish). i'm off all next wk but may run in to bend a few things.
what are you lookin for?
got pics of the brackets you mention?
this is the 3/8 i have i got quite a few pieces. you can see the finish on them.........i broke 1 trying to bend it the wrong way.
what are you lookin for?
got pics of the brackets you mention?
this is the 3/8 i have i got quite a few pieces. you can see the finish on them.........i broke 1 trying to bend it the wrong way.
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I spent most of yesterday playing around with exhaust routing and thinking through things.
In the late afternoon I got started on the engine side motor mounts.
In the late afternoon I got started on the engine side motor mounts.
How did you determine the sizes/thickness of the plate used for the mounts and gussets? Looks kind of small to the untrained/unfamiliar eye... Wondering if there’s a method to it all or just eyeballing it.
Any idea if the frame needs to be beefed up for the weight of then engine. Read that Jeep did something of the likes when they swapped in the bigger and heavier V8 in their Wrangler 392.
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