Has ANYONE ever swapped a 8.1L 496 LS motor into anything???
08-15-2014, 12:15 PM
#21
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8.1's are based on traditional big block chevy, but share electronics with LSx family. 24x crank trigger, 1x cam trigger, coil per cylinder, drive by wire, etc...
Nice thing about the 8100 is all the bolt holes are in the same place as traditional BBC, except all holes are METRIC thread. The 8.1 is a tall deck engine, 10.2 vs 9.8 " deck height, so , head are higher, and outward toward fenders a little more then regular big block. Header patter IS THE SAME, metric holes.
Oil pan is unique, its aluminum, so options for fitment is slim. Mark 5 and Mark 6 oil pans ARE different. The valve cover patter is almost same as traditional BBC, except for one hole on each side. I was able to oval shape the hole in some stamped steel valve covers to make them work. The heads are held on with two additional head bolts, and the pattern is moved around. So 8100 heads WILL NOT go on traditional BBC, or vice verse.
The 8100 is net lash, no adjutment to valve train. However, you can get a stud from ARP with metric threads on bottom, standard on top, and run regular big block chevy adjustable valve train stuff.
Camshaft is roller, you CAN install older Mark V, Mark VI roller cam's. This will change firing order back to 1-8-4-3-6-5-7-2. In stock form, the 8100 shares SAME firing order as LSx family. Programming would need done of course to change injector bank assignment.
I've had two 8100, and both of them suffered piston failures in the end. I've heard they have weak pistons, but I don't know. I know the motor is a torque monster, and I'd love to find another one sometime and build it.
Nice thing about the 8100 is all the bolt holes are in the same place as traditional BBC, except all holes are METRIC thread. The 8.1 is a tall deck engine, 10.2 vs 9.8 " deck height, so , head are higher, and outward toward fenders a little more then regular big block. Header patter IS THE SAME, metric holes.
Oil pan is unique, its aluminum, so options for fitment is slim. Mark 5 and Mark 6 oil pans ARE different. The valve cover patter is almost same as traditional BBC, except for one hole on each side. I was able to oval shape the hole in some stamped steel valve covers to make them work. The heads are held on with two additional head bolts, and the pattern is moved around. So 8100 heads WILL NOT go on traditional BBC, or vice verse.
The 8100 is net lash, no adjutment to valve train. However, you can get a stud from ARP with metric threads on bottom, standard on top, and run regular big block chevy adjustable valve train stuff.
Camshaft is roller, you CAN install older Mark V, Mark VI roller cam's. This will change firing order back to 1-8-4-3-6-5-7-2. In stock form, the 8100 shares SAME firing order as LSx family. Programming would need done of course to change injector bank assignment.
I've had two 8100, and both of them suffered piston failures in the end. I've heard they have weak pistons, but I don't know. I know the motor is a torque monster, and I'd love to find another one sometime and build it.
10-28-2014, 11:24 AM
#22
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03-22-2016, 12:35 AM
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8.1 dart intake 
03-24-2016, 12:15 AM
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Thank you!
I am swapping one of these beasts into my third gen camaro and want to stick with a carburetor since I have so many of them.
06-21-2018, 11:33 AM
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I have stuffed an 8.1 with Allison 5 speed out of a 2001 2500HD into a 1971 Buick Skylark. It is bored .030" over with a 4.75" crank making it over 9.0L and running a 2.9L Whipple Supercharger. This engine can make massive power with tremendous torque straight off idle. The swap was fairly simple and I am considering what I will swap one into next, just a much milder build.
10-13-2018, 07:39 PM
#29
Need pics and video of said sky lark, also join my 8.1 facebook group
www.facebook.com/groups/1556016757949905/
www.facebook.com/groups/1556016757949905/
10-14-2018, 06:58 AM
#32
�� If only... I’d guess on the order of 900 lbs
I think I guessed low - a little research indicates the fully dressed 8.1L weighs in at close to 750 lbs. and the Allison 1000 is 330 lbs. dry.... Yikes.
I think I guessed low - a little research indicates the fully dressed 8.1L weighs in at close to 750 lbs. and the Allison 1000 is 330 lbs. dry.... Yikes.
Last edited by Michael Yount; 10-14-2018 at 07:26 AM.
10-14-2018, 10:31 AM
#33
TECH Senior Member
The only time I have seen the 8.1 swapped into anything here was a thread where a guy put one into an Airstream motorhome in place of an old 454(7.4L). MUCH more power AND way better fuel mileage. The 8.1 was injected and coil on plug ignition. Its operation system was just like an LS
10-14-2018, 10:56 AM
#35
TECH Senior Member
Yeah, that actually made me a believer in big blocks as something besides gutless gas guzzling boat anchors. They have improved somewhat... lol
10-14-2018, 11:30 AM
#37
TECH Senior Member
07-11-2019, 10:43 PM
#40
Launching!
Several of those have gone into square bodies. Builds on ck5. They have some potential, but they need a set of heads as they're very restrictive. Only one place I know of that makes heads, builds them for race boats. Very pricey. But they're a good tow engine.
