Originally tagged the “Double Rocker Shaft V8,” it soon became “the Hemi.” It made a lot more power than the rest of the car engines that were available at that time, so some people say Chrysler started the “horsepower wars” with the Hemi.
• With its good ports and bigger valves that opened away from the walls it had better volumetric efficiency.
• It had a low “surface-to-volume ratio” which gave it better thermal efficiency so it made more power.
So, with the best chamber, plenty of cubes, generous ports and better airflow, it was a winner – except that it was heavy (a 392 cid Chrysler weighed 737 pounds), more complicated and more expensive to build – so it eventually lost out to the big wedge motors like the 383, 400 and the 440 cid.
Chrysler has built three different families of Hemi mo- tors since 1951. There were 12 different engines in the first generation that ranged from a 241 cid Dodge to the 392 cid Chrysler and spanned almost ten years from 1951 through 1958.
The only engine in the second generation was the legendary 426 that was built from 1964 thru 1971. It was originally intended to be used for racing at NHRA and NASCAR tracks, but it ended up on the street because NASCAR told Chrysler that they had to sell at least 500 cars with the “street Hemi” to make it legal for the Daytona 500 that year. It died in ’71 because NASCAR had outlawed it on the track and the emissions police frowned on it for the street.
But in the late ’90s, when Chrysler realized that it needed a new engine with more power and torque for the 2003 Ram pickups, the third generation Hemi was born. Since then, it’s been used in SUVs, Jeeps and RWD cars, too. Some purists say it’s not a real Hemi because it has squish areas on both sides of the chamber, but as Engine Builder technical of the engines (and from which much of this information has been drawn) it’s close enough for most of us.
It has a hemi-shaped chamber with the valves canted toward the middle of the cylinder, four rocker shafts with good valvetrain geometry and generous ports. And, it incorporates some modern technology including aluminum heads, dual spark plugs, roller lifters and a “multi-displacement system” (MDS) that deactivates four cylinders under light loads. It can pump out 345 hp and still get 21 mpg on the road.
Available in both 5.7L and the 6.1L configurations, it reintroduced the phrase “That thing got a Hemi?” into our culture.
When it comes to rebuilding this popular engine, it may be difficult for you to know where you stand on price. While you should never set your pricing directly based on what any of your competition does, it’s always helpful to understand the ballpark in which you’re playing.
To help, we present here our current labor costing study on rebuilding late model Hemi engines, with a look at national and regional average labor charges. The study covers various head, block and crankshaft service procedures as well as miscellaneous labor charges.
The individual charts begin below. In addition, the detailed chart on page 28 represents the national average, median and mode labor charges for all of the procedures covered in our survey.
The “average” for a specific labor charge is the result of adding all of the charges for that service from all respondents and then dividing that number by the total number of respondents. The “median” is the result of ranking all of the survey responses from highest to lowest and then finding the number that falls exactly in the middle. The “mode” is simply the most-often reported num- ber from all survey respondents.
Additionally, our chart provides the “95% Confidence Interval (CI)” range. In real terms, if you were to ask all of the machine shops in the country what their labor rates were for each operation, it is 95 percent certain that the “true” average labor cost would fall within this range.
You may find your prices are ei- ther lower or higher than these aver- ages. Don’t worry – as we’ve tried to explain for years, we believe that knowing your costs is the only sure way to set your pricing. You may have updated equipment that allows you to be more productive than these charts indicate.
Conversely, you may find your costs are significantly higher than others in your same area. These dis- crepancies should not be seen as indicating that your costs are either too high or too low. But they will hopefully give you an incentive to look carefully at what you charge for services…and why.
“Some shops may include certain operations in the process of doing others,” says Bob Roberts, Market Research Manager for Babcox Research. “This may lead to a higher dollar amount charged. Additionally, some shops may have given us an ‘each’ price when we wanted ‘all’ or they may have included an ‘all’ when we asked ‘price each.’”
In a few cases, we did not provide a regional breakdown for certain services listed below. The informa- tion provided did not vary enough to give interesting regional breakdowns for a few categories, so only the na- tional information is presented.
Roberts says while the overall results are statistically reliable, the way some respondents answered the question may have skewed certain numbers slightly.
“Some shops reported to us that they perform some repairs on a ‘time’ basis. We did not use a dollar- per-hour value if they provided it. A few shops price all their repairs on a ‘time’ basis. This is most common with welding repairs. Some shops do not perform all the operations listed and this leads to a smaller number of observations and thus a less reliable average,” Roberts says. However, he says “In all cases, the national aver- age will be the most accurate figure.”
• You can download the complete survey, including charts here.
• You can read Doug Anderson’s complete article on rebuilding the 5.7/6.1L Hemi here.
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