The 906 and 062 Vortec heads are two popular cylinder head options used in small-block Chevy engines. However, 062 has slightly larger valves than 906 Vortec Heads.
While 906 and 062 Vortec Heads share some similarities, there are also some notable differences.
Here is a quick comparison chart highlighting the significant specifications of 906 and 062 Vortec Heads.
Quick Comparison Table
| Specifications | 906 Vortec Head | 062 Vortec Head |
| Performance | Low Power Potentiality | High Power Potentiality |
| Compatibility | Compatible with specific engines | Compatible with all engines |
| Valves | 1.94-inch intake and 1.50-inch exhaust valves | 1.94-inch intake and 1.60-inch exhaust valves |
| Application | Mild Street Build | High Performance Strip |
| Price | Affordable | Expensive |
Key Differences Between 906 And 062 Vortec Heads
The above comparison chart gave you a brief idea of the specifications of 906 and 062 Vortec Heads. It’s time to identify the critical features of the two products.
- Features
General Motors introduced the 906 and 062 Vortec heads in the mid-1990s, and both are based on the same basic design.
Both heads feature a small combustion chamber, which helps to increase compression and improve performance.
They also feature improved airflow over earlier small block Chevy heads, thanks to redesigned intake and exhaust ports.
The valve size is a notable difference between the 906 and 062 Vortec heads.
The 906 heads have 1.94-inch intake valves and 1.50-inch exhaust valves, while the 062 heads have slightly larger 1.94-inch intake valves and 1.60-inch exhaust valves.
This difference in valve size can affect the engine’s overall performance, as we will discuss later in this article.
Also Read: Differences Between Full Tilt And PDI Manifolds.
- Performance
When it comes to performance, the 906 and 062 Vortec heads are both capable of delivering significant power gains over stock small block Chevy heads.
However, there are some differences in their performance capabilities.
The 062 Vortec heads are generally considered to be the better performer.
This is mainly due to the larger exhaust valves, which allow for improved exhaust flow and better scavenging.
The larger valves also allow for more aggressive cam profiles, which can further improve performance.
Additionally, the 062 heads were introduced later than the 906 heads and benefitted from minor design improvements, such as improved coolant flow.
That being said, the 906 Vortec heads are still an excellent option for those looking to improve the performance of their small-block Chevy engine.
While they may offer less power potential than the 062 heads, they can still deliver significant gains over stock heads.
However, smaller exhaust valves can be a limiting factor, particularly when running high-lift camshafts.
- Compatibility
Regarding compatibility, the 906 and 062 Vortec heads are generally interchangeable with other small-block Chevy heads. However, there are a few things to remember when swapping between these heads.
Firstly, the 062 heads require a different intake manifold than the 906 heads. This is due to the larger intake port design of the 062 heads.
If swapping from 906 heads to 062 heads, you must also exchange to a compatible intake manifold.
Secondly, the larger exhaust valves on the 062 heads may require some modifications to the exhaust system to prevent interference.
This is particularly true when using headers, as some header designs may differ from larger valves.
Finally, it is essential to note that both the 906 and 062 Vortec heads require different rocker arms than earlier small-block Chevy heads.
This is due to the various valve angles and valve stem heights used in the Vortec heads. If you swap Vortec heads from earlier heads, you must change to compatible rocker arms.
- Application
Another factor to consider when choosing between the 906 and 062 Vortec heads is the specific application for which they will be used.
While both heads can deliver significant power gains, their ideal applications may differ.
For example, the 062 heads may be better for a high-performance street or strip application where maximum power output is desired.
The larger exhaust valves and improved airflow can support high-horsepower builds.
On the other hand, the 906 heads may be a better choice for a more mild street build or a truck application, where low-end torque and drivability are essential.
The smaller exhaust valves may not be a limiting factor in these types of applications, and the smaller combustion chamber can help to increase low-end power.
- Cost
Cost is an essential factor to consider when choosing between the 906 and 062 Vortec heads.
Generally speaking, the 062 heads are slightly more expensive than the 906 heads.
This is partly due to their larger exhaust valves, which require more machining during production.
Additionally, the 062 heads are generally considered to be the more desirable of the two, which can drive up their price in the aftermarket.
Which Vortec Head Is Perfect For You?
062 Vortec Heads lead the race against 906 due to their exceptional power potentiality, better compatibility, and excellent durability.
Moreover, 062 heads make a better choice for a high-performance street or strip application where maximum power output is desired.
Price is the only drawback of 062 Vortec Heads. However, the premium quality and superior performance justify the high price range of the product.
Overall, 062 heads tick all the boxes of the best cylinder head for your car’s engine.
Also Read: Popular LMM EGR Delete Kits.
Frequently Asked Questions (FAQ)
062 has slightly larger valves and provides better power potential than 906 Vortec Heads.
Larger Pot Heads draw the difference in Vortec heads products.
GM L-31, GMPP Fast Burn, 906 Vortec, 062 Vortec, and Dart IE are renowned products from Vortec Heads.
Vortec heads have a maximum valve lift of 470-480”.
Vortec heads are only compatible with earlier-generational blocks.
Conclusion
062 Vortec Heads is the winner in this comparison of 902 and 062 Vortec heads.
The combination of exceptional performance, larger valves, and better compatibility makes 062 Vortec heads.
Therefore, if you are searching for the best cylinder head options for your engine, then 062 Vortec Head is a perfect choice.
There is so much miss-information in this article it is not even close to being accurate. I would do some research on this and publish a revised version so that those of us that have actually known the ins and outs of these cylinder heads for the past 28 years are not laughing at this flat out wrong information.
1st) Exhaust valves are the same 1.5″ and both castings share the same exhaust port shape and location.
2nd) 062s and 906s were both introduced in 1996. The 906 can have EITHER the pressed in exhaust seat or the induction hardened seat depending on the application.
3rd) The OE heads cast in Saint Catherines, Ontario through about 2002 were higher flowing but had a thinner deck and more crack prone in the decks than the ones cast in Mexico. The Mexico heads were more prone to cracking in the induction hardened exhaust seats when equipped, especially between the intake and exhaust seats.
4th) GM shifted the production to Mexico around 2002 as the L31 350 engine was used in Mexican built GMT800s through the 2007 model year for the Mexican/South American markets. They also kept casting them for marine, industrial and crate engines as well. By the time the core boxes made it to Mexico and GM had revised the deck thickness the intake ports had reduced in size from 170cc to 159cc and the heads lost a considerable amount of flow. From 239 cfm @ 0.500 for a good Canadian 906 down to 210 cfm @ 0.400 with a port stall at 0.450″ on a Mexican 062. 906 and 062 castings were both cast in Canada or Mexico depending on when they were cast.
5th) These heads use the same raised runner intake manifold as do the Vortec 305 heads with casting numbers ending in 059 or 520. The 062 and 906 castings use the same intake manifold.
6th) The 062 head is not compatible with every application. The 906s insert/hardened valve seat was a GM remedy for the cylinder head cracking in certain high load, high heat applications such as a heavy-duty truck towing a trailer, marine use and industrial engines running on LPG or Natural gas. An 062 head with its induction hardened seat will experience cracking in the exhaust seats when used in these applications.
7th) You claim an 062 is a higher performance head and that is simply not true especially comparing a Mexican cast 062 with a Canadian cast 906 with the normal induction hardened exhaust seat and multi-angle exhaust valve. The difference is a solid 20 hp gain with the early 906 head. The reality is the Canadian casting is a higher performance cylinder head than the Mexican casting. GM may have fixed the Mexican castings later in the production run before stopping the Mexican production but from 2002 through about 2017 they were the same 159cc runner, weaker flowing heads throughout that production run.
In short correct your article with the actual correct information.