I'm swapping a 4.8 and 4L60e out of an '04 Tahoe into an '89 Firebird with a 2.8 V6 and a 700R4.

I'm going to be using 4th gen Camaro engine mounts, and I want to be able to reuse the factory driveshaft. I'm not concerned about the transmission crossmember, I can fabricate or modify that as needed.

I'm down to two choices:

UMI:
http://umiperformance.com/catalog/in...roducts_id=692

Or Hooker Blackheart mounts:

https://www.holley.com/products/exha...ts/71221003HKR

The Hooker mounts look great, and say that they have the proper mounting heights for each side, but they do not guarantee the ability to reuse the original driveshaft.
The UMI mounts are adjustable, but I don't want my engine to be lop-sided in the engine bay and hit the HVAC box (I'm going to be using the factory A/C box, and I'm notching my K-member for the compressor).

Thank you in advance.

 

I think you would be happy with either, the UMI has more adjustment built in which could be good or bad.

Match the trans cross member with the same company and everything should line up. Leave the mounts loose and when you get the engine in the car center the trans tail in the trans tunnel and the engine should fall into center and alignment in the bay. Then tighten down the mounts.

I used a BMR K-member and I wish it set the engine an 1/2 inch or more forward. Any mount you will be able to use the stock drive shaft. Both the 89 and the 00 drive shaft fit in my car when done... I am using the 00 because its aluminum. I'm actually going to loosen the k-member and see if I can get it forward just a little so I have a little more clearance on the firewall.

 

I used the ones from Hawks. If I had to do it again I would use the Blackheart ones and transmission crossmember. I used the blackheart exhaust, which sounds great, but had to modify it to work because of the Hawks mount plates. I think the Blackheart ones push the engine a little bit forward which is nice for clearance.

 

Thanks for the input, guys.

I think I'm going to go with the UMI mounts because of their adjustability, unless someone talks me out of them.

 

If you are using the stock kmember I have a set of these brackets for sale. 99% brand new. PM me if interested.

 

Hi looking for some guidance, I am pulling my LO3 out of my 89 Formula and putting in a 4.8 out of a Silverado. I want to use the AC, - I see you did this to the same car can you pont me in the right direction? What motor mounts did you use? I also want to use the original drive shaft. I will be putting in a 460 le - did you have to modify anything for the transmission to fit? Anything that can help with this project would be appreciated. What did you doe for the ECM and wire harness?
Thank you in advance

 

I did use the UMI frame perches with LS1 motor mounts. I was able to reuse the factory driveshaft. I had to modify the trans crossmember to get the newer syle 4L60 to fit.; no big deal.

ECM is mounted in the factory 3rd gen location - I had to extend the truck harness.

This is my build thread.