What is special about double hump heads?
These heads got their nickname because of the raised identification shape on the each end. Because of this, many racers will assume that just because they’ve found or purchased a set of Chevy heads with the infamous raised double hump on the ends, they’ve got the best thing going.
How much horsepower does double hump heads add?
Stock “double hump” heads flow 202 cfm intake and 141 cfm on the exhaust. If you must maintain a stock looking port, consider our “Undercover Porting”. With our “Undercover Ported” they will flow 220-230 cfm intake and 165 cfm exhaust. This flow improvement will add 15 to 25 horsepower to your engine.
Are Vortec heads better than double hump heads?
The L31 Vortec heads have larger ports than the older Gen I cast steel heads, so they outflow the older heads. The Vortec heads are a little bit lighter than the older heads and have a “kidney” or “heart” shaped combustion chamber that is more efficient than the double hump chamber.
What are 202 heads?
“202” refers to the intake valve diameter of 2.02″. Fords and Chevys usually don’t have an intake problem… they usually have an exhaust problem.
How much do camel hump heads flow?
Typical Camel humps only flow 195 CFM. There may be some castings that flow 203-205 CFM but the Vortec out flows all of them out of the box. Porting can increase the flow of either head but typically costs more than just buying better heads.
How much HP gain with Vortec heads?
Most of these small block Chevy heads offer a power increase of around 40 hp, and even the iron Vortec heads were worth 20 hp over stock. The two best small block Chevy heads in terms of peak horsepower were worth more than 60 hp. But, as you’ll see, there’s much more to the story, so read on.
What is a bowtie head?
Vortec Bowtie cylinder heads are the most powerful cast-iron heads offered by Chevrolet Performance. The heads provide outstanding low-lift flow numbers (the more air you flow, the more potential power) and Fast Burn performance all in an affordable, cast-iron head.
What is a head with a double hump casting?
Heads with short double-hump casting marks were used in later high-performance SBCs. Most of these heads had accessory bolt holes and were identified with casting numbers ending in 186 or 492. They were used from ’68 through ’72 on 302 CI Z-28 engines as well as ’70 through ’72 in LT-1 350 CI Corvette/Z-28 engines.
How much horsepower does a Chevy double hump head make?
This combination, along with the Duntov solid lifter cam, produced 360hp or 340hp with the single Carter 4-bbl carburetor. The success of these heads cause every Chevy cylinder head with the double hump casting identifier to be referred to as fuelie heads for an entire generation of hot rodders.
What kind of cylinder heads does a 1969 Chevy Camaro have?
Casting number 3927186 cylinder heads with swirl-polished valves were used on the 1969 Chevrolet Camaro Z28 302ci V8 engine. Photo from GM Heritage Center The cylinder head identifier was still the iconic double camel humps but the size of the humps were noticeably smaller.
How do I identify a Chevy cylinder head?
Chevy cylinder head Identification – Small block casting numbers, Big block cylinder head, camel back heads, double hump heads Find cast numbers Cylinder Head ID Use these casting numbers to identify the heads you have. Small Block Casting numbers