tilley52

Hello, i have a 1990 GMC Suburban 7.4 TBI, it has always been a dog. I have had of for a couple years and it never had the grunt and torque of other older 454's that i have had, I have had the heads off because when i bought it it had lost a timing chain and ran valves into pistons. I noticed at that time how small the rect. ports on the heads were, they seem VERY small and restricitve. Well its time for a rebuild now and i want to change the heads and try and make a little more grunt for towing, any ideas what i need to look for for casting numbers, i dont mind having to change the manifold to an oval port if needed, seems lots of people are saying 049 casting. keep in mind it will need to smog thanks in advance

JUICED96Z

iTrader: (2)

I would go with aluminum heads if you have not, however the main problem is the weight of that truck.

I have 14011077 heads but I doubt you will be able to find some, I found a set the other day going for 2k.

Id look for some nice D port (exhaust) aluminum BBC heads.

Mine are C's but having them ported and convereted to D's next winter.