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Front Suspension FAQs
An overview of Independent vs. Axle front-ends
  “I’ll be damned if I ever drive a hot rod with an independent front suspension!”

“I’ll be damned if I ever drive a hot rod with an axle front suspension!”

We’ve all heard this countless times.  And generally with a fair amount of emotion.  The bottom line is this – an Independent Front Suspension (IFS) will ride and handle better than a traditional cross- or parallel-spring front axle.  Hard to argue.  But some people simply prefer the looks of the axle front end and are willing to sacrifice some comfort to achieve this.  Form over function is nothing new in hot rodding.  With upgrades like disc brakes and brand-new, well made components, an axle front end can provide years of safe, comfortable driving.  Some folks, however, prefer the looks of the IFS and enjoy the better driving experience that goes with it.  Like the never-ending Chevy vs. Ford argument, it comes down to personal preference and what you think is best for your project.
Axle front-ends
  Traditional Cross-Spring Solid Axle – So classic it hardly needs any introduction and the one you see 99% of the time. The aftermarket kits available are all modeled after the early Ford design and use a transverse leaf spring mounted perpendicular to the frame rails attached to the solid I-beam or tube axle. The steering is usually a cross-steer set up with the drag link going from the driver’s side steering box to the passenger side steering arm. The box can be a converted car box, such as a Vega, Mustang, or GM manual or power unit. Unisteer also makes a Cross-Steer rack and pinion that is a direct bolt in for the Vega box. Many options are available such as depth of drop, style of axle, 4-bar vs. hairpins, show finishes, etc. NOTE: Sometimes referred to incorrectly as a ‘straight axle’, but this front end will always have a dropped axle. See the Gasser section below for info on a straight axle front end. Pros: Traditional look; acceptable performance; one-size-fits-all, so make/model specific parts not needed Cons: most labor intensive to install due to the many brackets needed for whole system; ride quality less than IFS; as costly as most IFS systems Recommended Applications: open wheeled cars; hot rods where the traditional look is critical Products Offered: Pete & Jakes or TCI Axle Front End packages

Suicide Front Axle
– Very similar to the above but the spring mounts to a perch hanging out from the front end of the frame crossmember rather than under the crossmember. This allows the front end to be lowered further because the springs won’t interfere with the frame rails as they would in the traditional front end. Usually requires the use of push-pull steering like a reversed Corvair box, and generally the frame and/or wheelbase is stretched to put the axle in front of the grill and radiator. Very common in T-buckets and slammed rat rods. Pros: More radical Traditional look; gets LOW! ; one-size-fits-all, so make/model specific parts not needed Cons: most labor intensive to install due to the many brackets needed for whole system; ride quality less than IFS; as costly as most IFS systems; some custom fabrication usually required Recommended Applications: T-buckets; open wheeled cars; hot rods where the traditional look is critical Products Offered: Pete & Jakes Suicide Axle Front End

“Gasser” Solid Front Axle – Uses a true ‘straight’ axle with no drop and high-arch parallel leaf springs to get the nose-high gasser stance. Can use either a cross-steer or push-pull set up. Every make and model built has been run as a gasser throughout the years with '41 Willys, '37 Chevys and even '32 Ford Vickys being some classic examples. Pros: only option for a gasser (replica or race car) Cons: most labor intensive to install due to the many brackets needed for whole system; ride quality on street is poor; as costly as most IFS systems; some custom fabrication usually required; no true ‘bolt-in’ kits available Recommended Applications: full-fendered gassers Products Offered: Call for a custom package built to your specs
Coil-Over Front-Ends: Kugel Komponents, Heidts Superide
  These systems are designed for better looks and better performance, and work in many applications where the Mustang II does not.  For fenderless cars, where the front suspension is exposed, these are both much cleaner and more attractive.  Certain fendered cars, like the ’32 Ford or ’33 Chevy, have front fenders that come down and bolt to the top of the frame rail.  The upper control arm bracket on both of these IFSs mount outside the frame rail permitting use of and clearance for stock front fenders without modification.  The open-front fenders on this early generation of street rods also keeps the IFS visible even with the fenders installed, making these good looking components a better choice.  As both come standard with coil-over shocks, and the Kugel also with a sway bar, both will out handle the base Mustang II IFS.  Kugel Komponents and Heidts kits are offered and both are excellent choices.  The Kugel kit offers exceptional quality and looks, with upgrades such as their Show Package and Cast Stainless control arms that really set it apart.  Their crossmember design and pre-assembled components also eases installation.  The Heidt’s Superide and Superide II also have great looks and performance, and offer an excellent IFS for a little less money.


Pros: best looking and performing IFS; fits where Mustang II does not; easier installation (Kugel IFS)

Cons: more expensive than MII

Recommended Applications: fenderless cars; Pre-1933 full fendered Fords; pre-1934 full fendered Chevys; street rodders wanting the best looking IFS
Mustang II IFS
  Mustang II – Originally these parts were pulled from the wrecking yard and re-purposed on street rods and trucks.  The original geometry works very well, and the aftermarket kits available today have all been beefed up to handle the higher horsepower and weight of the cars we are building.  The Mustang II IFS will greatly improve the handling and ride of your rod, especially with optional coil-over shocks and anti-roll bars.  We offer Mustang front ends from two leaders in the industry: Heidts and Total Cost Involved/TCI.  Both make excellent systems that we use on the chassis we build.  Each company offers a slightly different options, pricing, and applications.

Pros: least expensive IFS, very good performance

Cons: not the best looking, best if used under full fendered cars and trucks

Recommended Applications: full fendered cars and trucks; 1933 and newer Fords; 1934 and newer Chevys; many others
Pinched-Nose IFS
  Pinched Nose IFS – Both Kugel Komponents and Heidts offer an IFS specifically for pinched nose hot rods.  This is most commonly seen on a ’32 Ford where the front from horns are removed and the frame rails are moved inward to match the hood side line and terminate behind the grill shell.  The IFS systems made for this application have a narrowed crossmember and lengthened control arms to maintain the desired appearance and proper track width.  We have also used these in our pinched-nose ’33 Ford Low Boy Roadster and our ’27 Ford Trac T.  Each is offered with traditional coil-over shocks within the control arms as well as an inboard mounting design that hides the coil-overs behind the grill.

Pros: Only IFS system available for pinched nose applications; great looks and performance.

Cons: more expensive than other IFS systems; sway bar not available

Recommended Applications: any pinched nose street rod

Products Offered: (CALL for details and pricing)

Kugel Hi Boy IFS – Comes only in fully polished stainless, it is also available as a completely assembled frame stub that eases installation.    

Kugel Indy Style IFS – Moves the coil-overs inboard, behind the grill.  Comes only in fully polished stainless, it is also available as a completely assembled frame stub that eases installation.    

Heidts Open Wheel   - Available in plain, paintable steel with polished stainless available as an upgrade.  Full assembly required.

Heidts Inboard Shock Open Wheel  - Moves the coil-overs inboard, behind the grill.  Available in plain, paintable steel with polished stainless available as an upgrade.  Full assembly required.

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