Exhaust Manifolds

Q: Exhaust Manifolds

The exhaust manifolds on my 1968 Firebird 350 are cracked (both sides). I’ve been having a hard time finding a pair as most yards I’ve called either don’t have them or don’t know whether they have the right ones. One question i have is whether the manifolds from the “400” engine will be the same. Any insight will be very helpfull, summer is here and I desperately want to get on the road.

A: You can get the repro Long Branch Cast Iron Exhaust manifolds for around $325 pr. These are nice copies of the one’s originally used on HO & Ram Air 1st Gen. Firebirds… and cast using Ductile Iron..much better than originals. One other note.. be careful of buying used manifolds…. after 30yrs and countless temperature changes, many are bound to have stress fractures and/or cracks. I’ve had several pairs over the years (various styles) and those that needed repairs were usually much worse than first glance….many times unrepairable. Only the Ram Air & H.O. Exhaust Manifolds are considered difficult to find…all others can be found for around $100 pair. As far as usage…. The Following ‘D’-Port Exhaust manifolds will fit 1969 Firebird V-8’s

pt. # 9779325(RH)...63 T/4, 63-66 T/8-P/8, 1967-1968 F/8-T/8-P/8 (exc HO/RA)
pt. # 9777755(LH)...67- 1968 F/8, 
pt. # 9791607(RH)...67- 1969 F/8 Ram Air, H.O., 1968 P/8 428 H.O.
pt. # 9779493(RH)...67- 1969 F/8 Ram Air, H.O., 1968 P/8 428 H.O.
pt. # 9779495(LH)...67- 1969 F/8 Ram Air, H.O., 1968 P/8 428 H.O.
pt. # 9777641(RH)...67 GTO Ram Air, H.O.
pt. # 9777646(LH)...67 GTO Ram Air, H.O.
pt. # 490802(RH)....68 GTO Ram Air, H.O.
pt. # 478141(LH)....68 GTO Ram Air, H.O.
pt. # 9796992(RH)...69 - 72 F/8-T/8-P/8 exc.H.O./RA, 307
pt. # 9796155(LH)...69 F/8 exc H.O./RA
pt. # 9797073(RH)...69 F/8-P/8 RAIII, H.O.

*Basically…65-70 Pontiac Manifolds/Headers interchange with 1967, 1968, 1969 Firebird’s.
*The separate flange may vary btwn Full-Size Pontiac’s and Firebird’s.
*Also, the Ram Air, H.O. Manifolds used a special aluminum oil filter adaptor.

A: I have a 1968 350 and I just got exhaust manifolds for it from a junk yard, they were fron a 73 350 pontiac, and fit just fine

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