HSD RTM Eliminator (or Neville 8’s)
These are an excellent entry level head flowing 20-30 cfm better than stock 308 heads all through the valve range so if you’re pimping your old 308 or 253 (different valve sizes for 253) chuck a set of these on you won’t be disappointed
These heads are done to a specific formula
- Chemically cleaned and crack tested
- New guides *4 angle valve seats
- Race throats
- Oversize L34 size valves
- Group C spec machining
- Basic port job
- Heavy duty spring kit chromoloy retainers and hardened locks
- Viton stem seals
The same principal applies to all makes and brands, we can modify all GM, Fords, Mopars to similar specs: oversize valves, throating, seating, port jobs spring upgrade. This formula is not exclusive to Holden heads.