Engine Alignment issues with BRP mounts on 2nd Gen firebird

[73 TA]

I'm having some issues with my BRP LS swap kit and was hoping someone could give me some pointers. I have a 1973 Firebird and swapping a LY6 and GTO T56. Doing some research here I saw that BRP has great swap kits, but when I installed it everything looks angled towards the driver side. At first I thought I was crazy but here is some evidence:

-On the transmission tunnel I had to cut more off the drive side and it appears that the shifter is left of center
-The transmission cross member does not line up with the middle bolt hole for the energy suspension mount
-Underneath, the driveshaft connection point doesn't look centered

Some background: when I was installing the motor mounts, the holes lined up with the 74-81 sub frame even though the car is a 73. But I don't think this changes the alignment. I've been emailing BRP for some help but they keep asking questions instead of giving solutions.

I am not opposed to slotting the engine mount holes, but this supposed to be a FBody specific perfect fit product. I wanted to verify with the internet experts before I start the hack job. I know a bunch of people have used these mounts so any advice is appreciated, Thank You!

[Toddoky]

I'm having some issues with my BRP LS swap kit and was hoping someone could give me some pointers. I have a 1973 Firebird and swapping a LY6 and GTO T56. Doing some research here I saw that BRP has great swap kits, but when I installed it everything looks angled towards the driver side. At first I thought I was crazy but here is some evidence:

-On the transmission tunnel I had to cut more off the drive side and it appears that the shifter is left of center
-The transmission cross member does not line up with the middle bolt hole for the energy suspension mount
-Underneath, the driveshaft connection point doesn't look centered

Some background: when I was installing the motor mounts, the holes lined up with the 74-81 sub frame even though the car is a 73. But I don't think this changes the alignment. I've been emailing BRP for some help but they keep asking questions instead of giving solutions.

I am not opposed to slotting the engine mount holes, but this supposed to be a FBody specific perfect fit product. I wanted to verify with the internet experts before I start the hack job. I know a bunch of people have used these mounts so any advice is appreciated, Thank You!

I think I may be able to help you here. There is a stock offset of the engine and transmission to the passenger side of roughly 3/8" or so and you need to find out from BRP whether their engine brackets and crossmember maintain that offset, provide some other amount of offset, or center the engine/transmission in the subframe.

If their kit does maintain the factory offset, it is possible that you could have the crossmember flipped around backwards, meaning the mounting hole offset would be going in the wrong direction and would produce an angled installed position of the engine/transmission instead of them being straight in the subframe.

[Camaross82]

I have just had a similar issue with my BRP mounts in my 69 Camaro. My passenger side mount was about a half inch taller than the drivers side. Didn't notice the difference until it was time to do the exhaust and the header was a lot closer to the floor than the other side. We wound up having to cut the mount and re weld it slowly so the poly wouldn't melt.

[73 TA]

I think I may be able to help you here. There is a stock offset of the engine and transmission to the passenger side of roughly 3/8" or so and you need to find out from BRP whether their engine brackets and crossmember maintain that offset, provide some other amount of offset, or center the engine/transmission in the subframe.

If their kit does maintain the factory offset, it is possible that you could have the crossmember flipped around backwards, meaning the mounting hole offset would be going in the wrong direction and would produce an angled installed position of the engine/transmission instead of them being straight in the subframe.

I understand what you are saying, but wouldn't take that into account when designing for each specific transmission. I know i had to select t56 when i purchased the kit so i assume they would send me the proper cross member to account for that offset.

[andrewb70]

I understand what you are saying, but wouldn't take that into account when designing for each specific transmission. I know i had to select t56 when i purchased the kit so i assume they would send me the proper cross member to account for that offset.

If the trans crossmember has the offset built in, you may have the cross member turned around, which to me actually looks like it might be the case. Rotate the crossmember (front to rear) and I bet it will get better. The trans looks like it is at an angle.

Andrew

[Toddoky]

I understand what you are saying, but wouldn't take that into account when designing for each specific transmission. I know i had to select t56 when i purchased the kit so i assume they would send me the proper cross member to account for that offset.

There is no fore/aft cantilever characteristic built into your crossmember; it is a straight beam that spans the width of the subframe. You can therefore probably put it in with the ends flipped either way and if the BRP kit maintains the stock offset to the passenger side one way will be correct and the other not. The quick way for you to confirm it is to measure the trans mount attachment holes in relation to the mounting holes on the end of the crossmember...if the trans mount holes are dead center in the crossmember then the BRP kit is designed to center the engine and trans in the subframe. If the trans mount holes are off-center, then you need to be sure that the offset is to the passenger side of your car and not to the driver side.

[73 TA]

There is no fore/aft cantilever characteristic built into your crossmember; it is a straight beam that spans the width of the subframe. You can therefore probably put it in with the ends flipped either way and if the BRP kit maintains the stock offset to the passenger side one way will be correct and the other not. The quick way for you to confirm it is to measure the trans mount attachment holes in relation to the mounting holes on the end of the crossmember...if the trans mount holes are dead center in the crossmember then the BRP kit is designed to center the engine and trans in the subframe. If the trans mount holes are off-center, then you need to be sure that the offset is to the passenger side of your car and not to the driver side.

Thanks Toddoky and andrewb70 for the advice, I measured the distance from the mounting holes to the transmission mount and it is dead center on the crossmember. To update, I talked to multiple BRP employees and Nick mentioned that he had never heard of the engine mounts fitting into the 74-81 hole locations with the 70-74 subframe. He agreed to drill out the holes in a new pair of engine mounts with the bolt holes drilled out to 1/2" so that I have more adjustment with the transmission. Talk about great customer service, I hope it works.