Tunnel mods for 6L80E or 6L90E?

[bkkpool]

I am in search of an engine and tranny and I really like the idea of a 6.0/6L90E combo. I could not find much info on fitment. Is there anyone who has installed this combo in our trucks? What tunnel mods are required if any?

[bkkpool]

Anyone?
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[bbadfred]

Subscrbed! Just bought a 6L90E today I will get under m7 67 tomorrow and let you know if noone else answers!

[bkkpool]

bbadfred did you get a chance to look under yours?

[Street Smart]

I have a 6.2 with a 6L80E in my Suburban. I ground the casting seem off the top of the case, and massaged the floor (low hump). It need to go up a little to give me the proper drive line angle, but its almost there. I didn`t want to cut the floor but i might install a high hump so i can play with the angle more.

[bbadfred]

I have an LQ9/4L60E engine trans. I must have the tall trans hump because I have plenty of room for the longer and larger diameter trans case and the 1 1/2 inch longer length. I have CCP motor mounts and trans crossmenber.

[Street Smart]

There`s a difference in the height of a 4L60E vs 6L80/90E. the six speed doesn`t slope down as much.

[Street Smart]

http://ls1tech.com/forums/conversion...80e-6l90e.html

[bkkpool]

That thread sort of helps but doesn't clearly answer whether or not if it will fit in our trucks. I hate to buy a trans and find out it doesn't fit.

[Street Smart]

It doesn`t fit with out mod`in the low hump floor.

[68 short step]

kinda get an idea,
http://67-72chevytrucks.com/vboard/s...=269754&page=8

[bkkpool]

That's what I was looking for. Thanks!!

[Hart_Rod]

If you have a factory high hump, will you have to mod anything?

[Street Smart]

Originally Posted by Hart_Rod

If you have a factory high hump, will you have to mod anything?

There should be plenty of room with the high hump floor.

[Hart_Rod]

Originally Posted by Street Smart

There should be plenty of room with the high hump floor.

Who's motor and transmission mounts are you using?
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[Street Smart]

I just used a plate style adapter, not sure of the brand, some left overs from a job. Reused the factory motor mounts. I had to lower the top of the motor mount bracket to clear the used set of headers i installed, but the motor height stayed the same.
I swapped the trans crossmember around 180* and made spacers so the mount would sit on the cross member at the right height.

[Street Smart]

http://67-72chevytrucks.com/gallery/...5&ppuser=74049

[69vetteside]

As mine originally came with a 4 speed would this be a high hump or low hump. it now has a t400 but they have built a custom console over it so i cant tell .CHEERS

[eric8]

Still don't know what to make of all this. I read this thread which pretty much says tunnel mods will be required, but spoke with Mark at Street and Performance who has done this swap and says he didn't recall any clearance issues on the 67-72 platform. What trucks came with the high hump tunnel? How do I know if mine has it?

[Hart_Rod]

Originally Posted by eric8

Still don't know what to make of all this. I read this thread which pretty much says tunnel mods will be required, but spoke with Mark at Street and Performance who has done this swap and says he didn't recall any clearance issues on the 67-72 platform. What trucks came with the high hump tunnel? How do I know if mine has it?

It all depends on where you locate the motor. If you move it all the way forward, you MIGHT be able to not install a high hump. If you move it all the way back (like I did) you will have to install a high hump....

[eric8]

Originally Posted by Hart_Rod

It all depends on where you locate the motor. If you move it all the way forward, you MIGHT be able to not install a high hump. If you move it all the way back (like I did) you will have to install a high hump....

Thanks Rob. Any idea what transmission tunnel you have?

[Hart_Rod]

67-72 Big block, 4x4 or 4 spd manual

[codeJbird]

I have the 6.0/6L80 combo in mine. It originally came with a low hump that had to be cut for a high hump cover. New holes were drilled for the high hump cover and it fit. No other cab mods were done.

[eric8]

Originally Posted by codeJbird

I have the 6.0/6L80 combo in mine. It originally came with a low hump that had to be cut for a high hump cover. New holes were drilled for the high hump cover and it fit. No other cab mods were done.

Did you use motor mount plates that keep the engine in the stock location?

[codeJbird]

Originally Posted by eric8

Did you use motor mount plates that keep the engine in the stock location?

It is close to stock location. I kept the mounts that came with the motor and fitted them to frame.