Hot Rod Forum banner

Hooker cast iron exhaust manifolds - good choice?

479 2
The Gen 1 SBC 350 in my K25 has one cracked stock exhaust manifold, and as a replacement I’m considering the Hooker iron manifolds (Hooker 8525HKR). Probably not that much better flow than stock, but I want something durable, and these do have bigger 2 1/2” outlets. If I used headers I would probably need something like the Hedman Elite with thicker flanges and tubes, and they are a lot more expensive.

In a couple reviews the posters mentioned difficulties with getting these to stay tightened down to stop leaks where they bolt to the head. I’m confused because it seems Ike it would work the same as the old stock manifolds. I also have aluminum heads and want to avoid tightening them down too much and stripping anything.

Could it just be poor gaskets are supplied with the manifolds? I use off-the-shelf gaskets from Autozone with my stock exhaust and have never had leaks.
1 - 2 of 2 Posts

· Registered
Joined
·
2,897 Posts
Discussion Starter · #3 ·
You bring up a good point about including a flex section in the system. My head pipes are bolted solidly to the stock exhaust manifolds and the only flex in the dual exhaust system mounting is the relatively short rubber hangers. The balance pipe adds even more rigidity to the system because both sides move as a unit.

My truck has straight axles, heavy duty springs and 10 ply rated tires, so the unloaded ride is fairly rough. I'm not worried about full length headers actually failing/leaking, but assume good 3/8" flanges will be needed to keep it all tight during the rough ride. Any leaks in the flange area really screw up the readings for my wide-band AFR gauge, and I rely on it to make sure everything is working right on the engine. Those Hooker cast iron manifolds seemed like an intermediate choice that might work well.
 
1 - 2 of 2 Posts
Top