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So this is what I have in mind. I might not even make it L shaped. I might leave the brackets over the top of the frame bolt it in than cut the crossmember to length and drill holes into the crossmember to bolt to the bracket. This way I dont have to drill into the subframe! Than whenever I want to remove my transmission I can just take off the 4 bolts at the bracket and my tranmission and crossmember will be loose. I may even weld the bracket to the subframe once everything is fixed and where I want it to get rid of any play/movement that might be in the bolts going from the subframe to the bracket.
The cure for your situation is a bracket that relocates the mount of the 4L80 transmission down and forward so that the mount can be attached to the Hooker 2nd-gen F-body T56 transmission crossmember. The attached image shows the type of bracket I'm speaking of as it is used with the Hooker 1st-gen F-body 4L80 transmission crossmember. I used the bracket again recently for installing a 4L80 in the Hooker SN95 and Fox Body Mustang LS swap applications and have an extra one I can send you if you want to use the Hooker 2nd-gen T56 crossmember. Send me a PM if you are interested.
If you were to remove the transmission mount from the transmission each time you wanted to remove the engine/transmission as an assembly, you could indeed leave the crossmember in place.
Here's an image of the 12616HKR crossmember in 2nd-gen F-body here in the engineering lab that is having a 4L80 installed behind a SB Chevy to do some development work...the set-up is basically how you would combine the two parts in your car.
I don't know what year your car is, but if it's a 74' or later model year there will be no holes in the frame in the location of the crossmember feet, so you'll have to use the supplied angle brackets that come with the crossmember to attach it to the frame.
70'-73' cars have crossmember attachment holes in the the pockets that the crossmembers sits it and may or may not line up with the crossember feet once you get the 4l80 adapter bracket bolted up to the crossmember...if they do great, if not, you would use the angle brackets like they are used for the later model year cars.
In the first picture you sent me it looked like the transmission was hard mounted, in this picture it looks like there is some sort of bushing. There is a difference in application for the two pictures you sent so will the one I get for my 1980 Firebird come with some sort of bushing or will I have to hard mount the trans to the cross member?
In the first picture you sent me it looked like the transmission was hard mounted, in this picture it looks like there is some sort of bushing. There is a difference in application for the two pictures you sent so will the one I get for my 1980 Firebird come with some sort of bushing or will I have to hard mount the trans to the cross member?
Both applications I showed pictures of use a transmission mount, you just can't see it in the first photo I sent you as it's obscured by the crossmember. The mount you'll need to use is a Prothane 7-1604.
There is the one I used. It's a little heavy but I think it was designed for a ls swap as it sat too low for my stock t350 mount.
I had to use the urathane one pictured above + 1/4" spacer to keep my distributer off the fire wall.
11-15-2017, 05:14 PM
