PRI 2015: New Billet LSX Pro Mod Cylinder Heads From Frankenstein

IMG_3402

Tucked away in the corner of one of the PRI Show’s monster-sized rooms last week was a booth staffed by none other than cylinder head specialist Chris Frank and his group of craftsmen from Frankenstein Racing Heads. On display was one of their brand-new, hot-out-of-the-CNC billet LSX Pro Mod cylinder heads on display. These heads are designed for all-out no-holds-barred competition.

“Our new LSX billet head is geared towards turbo Pro Mod; this particular head is solid with no water passages to be used with a turbo or blown alcohol-type combination,” says FRH’s Jesse Meagher. “We’re using a canted valve on both the intake and exhaust, with a valve angle that is optimal for a turbo- or supercharged application. We’ve got a nice big fat 70 cc combustion chamber, which we’ve added additional softening to in order to widen the tuning window and allow you to run tons of boost.”

We have the digital tools to make sure this thing was going to come out the first time and work properly. — Jesse Meagher, Frankenstein Racing Heads

Although the company is unwilling to release the proprietary intake and exhaust port volumes, they did explain that the intake valve checks in at 2.260-inch with an 8-degree angle, while the exhaust valve is 1.640-inch with a 5-degree angle.

Minimum bore size to be used with these is 4.125-inch to ensure the valves have enough room to breathe effectively. And although flow numbers are just a tool to be considered when developing an entire engine package, this particular cylinder head features an eye-popping 485 cfm flow through the intake port and 318 cfm through the exhaust port.

“We wanted to make these as beefy as we possibly could — the head’s built for half-inch head studs down all of the mains, and the surrounding bolts are 7/16-inch; everything comes with hardened steel inserts,” says Meagher.

“We’ve also oversized the rocker pad, added 7/16-inch bolt holes in the rocker stand area, and have added additional clearance over our previous design, for two reasons. One, we wanted to get some weight out of it. This head only weighs about six pounds more than its nearest equivalent, even though it’s radically stronger. We’ve added a lot of clearance in the pushrod area also, so we can run big fat half-inch pushrods and keep the valvetrain geometry running straight and true.”

Although it's difficult to show in photos, line of sight from the exhaust valve to the port exit is quite solid -- nearly the entire valve seat is visible from the port area.

Although it’s difficult to show in photos, line of sight from the exhaust valve to the port exit is stout — nearly the entire valve seat is visible from the port area.

During the development process, the team worked to take every potential scenario into account to ensure that the design could be fleshed out properly the first time around.

“We did a raised runner on both the intake and exhaust side; to be fair it’s kind of hard to say how much because we didn’t base it off of anything else. When we designed this, we started with the bolt pattern, Chris and I sat down and developed the valve angle, layout, and rotation that we wanted to get, and after that we just modeled it to see how it worked out. Then we tuned and tweaked it a little bit. It’s similar to the GM DR exhaust in terms of the height, and on the intake side we brought it up as high as possible to get a straight shot into the valve,” says Meagher.

Beef is the order of the day on these heads; the outer deck surface is contoured for strength, and the same stability is engineered into the spring pad and rocker stand area.

Many of the other fine details were touched on during the head’s development, also. Oil drainback holes all along the head plus two external connections offer the end-user lots of flexibility in terms of how the oil is dealt with. The spring pads are larger than factory and will accept an oversized triple spring to allow for the ultimate in valve control under massive amounts of boost.

Digital technology allows Meagher to develop the entire cylinder head in Solidworks before a single piece of aluminum is ever touched; in this instance he also paired the drawing with a model of the block, the offset lifters, and even a model of the pushrod dimensions. Extra time was spent to make the product unique including the curved area of the exhaust side of the cylinder head, which is designed to not only look good, but also make the cylinder head stronger.

“We have the digital tools to make sure this thing was going to come out the first time and work properly. From there, it’s just a matter of moving it over into Mastercam and fine-tuning the design so we not only get the unique function that we’re looking for, but also the unique look that we’re going for,” sums up Meagher.

He makes it sound so simple.

Chamber softening is done on the heads to permit a wider window for tuning adjustments; the amount and angle of softening, along with valve-seat materials is tailored per the application.

Chamber softening is done on the heads to permit a wider window for tuning adjustments; the amount and angle of softening, along with valve-seat materials is tailored per the application.

Article Sources

About the author

Jason Reiss

Jason draws on over 15 years of experience in the automotive publishing industry, and collaborates with many of the industry's movers and shakers to create compelling technical articles and high-quality race coverage.
Read My Articles

Horsepower delivered to your inbox.

Build your own custom newsletter with the content you love from EngineLabs, directly to your inbox, absolutely FREE!

Free WordPress Themes
EngineLabs NEWSLETTER - SIGN UP FREE!

We will safeguard your e-mail and only send content you request.

EngineLabs

We'll send you raw engine tech articles, news, features, and videos every week from EngineLabs.

EngineLabs

EngineLabs NEWSLETTER - SIGN UP FREE!

We will safeguard your e-mail and only send content you request.

EngineLabs

Thank you for your subscription.

Subscribe to more FREE Online Magazines!

We think you might like...



Late Model LS Vehicles

Drag Racing

Performance Driving

EngineLabs

Thank you for your subscription.

Subscribe to more FREE Online Magazines!

We think you might like...

  • Late Model LS Vehicles
  • Drag Racing
  • Performance Driving

EngineLabs

Thank you for your subscription.

Thank you for your subscription.

EngineLabs

Thank you for your subscription.

Thank you for your subscription.

Loading