That is a trans fluid cooler. When the engine was rebuilt they included it. I’m not entirely sure it was necessary because even though I enjoy getting on the gas I’ve never come close to pushing this build to the limits. Cheap insurance I suppose but I really wish it was mounted somewhere else.
1973 Mach 1 original H code 351c
Rebuilt into a 408c with the original rebuilt C6. Bought it in 2003, engine rebuild 2006-2007 and spent several years cruising around. It’s now been sitting for about 1 1/2 years while waiting to redo the electrical and fix the hood where I dropped a storage tote...
I have had my Mach 1 since about 2003 and bought it sight unseen off EBay motors after some long phone calls with the seller. What I got was a mainly original 1973 Mach1 with a busted #1 pushrod, which was disclosed. Sent it out for a total engine rebuild and got back a very nice 408c stroker...