Holley LS Swap Brackets 2004 Vette LS1 Clearance issue to OEM exhaust manifold and AC bracket?

[Shinobi68]

Since I finished the Holley swap pan over the weekend, I figured I would spend a little time on prepping the LS1 with my Holley swap parts. Today I figured I would install the engine brackets during my lunch break. I removed the driver's side (left) OEM engine bracket first, and when I went to install the Holley engine bracket it wouldn't drop into place without hitting the OEM exhaust manifold. Looks like it would need about 1/16" of clearance to fit with the manifold in place. I thought maybe I mistakenly grabbed the right-side bracket, but I noticed on all of the pics from my searches it confirmed the Holley instructions, indicating the clam shell mount box forward and the flat side of the engine bracket facing up.

I thought I would try loosening up the exhaust manifold to slide the bracket in around the bulge of the exhaust tube to get behind it a little, once in place I pressed the manifold back into place by hand but it was still making contact with the bracket/tab (see pic). Just curious if anybody else has ran across this, or if Vette OEM exhaust manifolds just don't work without clearancing the Holley Engine bracket or some of the cast steel on the manifold?

Then I moved over to the passenger side (right) and couldn't get the bracket to drop in because the AC Compressor/bracket was making contact. I removed the AC compressor and bracket and slid the engine mount into place, no issue with the right-side engine bracket making contract with the OEM exhaust manifold on the right side. I figured I was going to end up buying a mini-AC compressor and bracket by ICT to keep the AC low mount, or possibly go with a high mount AC bracket, as I don't want to notch the frame to retain the AC.

Looking to see if others have run across this issue, or if they had to slightly clearance the engine brackets to fit with OEM exhaust manifolds. I know that Holley states for use with the Black Heart system, but I didn't see anywhere that Holley stated their brackets would NOT work with the OEM AC bracket or OEM manifolds.

Thanks

 

[Shinobi68]

Well with no replies lol it looks like I'm the first one to have this problem or people are trying to not embarrass me. I'm thinking that there must be a reason for this, like maybe perhaps the C5 OEM exhaust manifolds aren't going to fit right when I go to drop the motor in and that I need to probably buy the Hooker Black Heart Exhaust Manifolds that will clear the bracket and sit tighter to the block next to the steering column.

Looks like Holley sells a Hooker 2.25" and 2.50" exhaust manifold outlet. Assuming I should opt for the 2.50" even though it's a stock LS1.

Any recommendations on a low mount AC bracket too while I'm at it?