G-Comp Buyer's Guide
If you’re lucky enough to own a piece of American muscle car history, you know that it’s hard to beat the feeling of rolling down the road in a 50 year old car that stops traffic and brings back all the best memories. But often the passage of time has caused us to forget that 60’s and 70’s suspension technology wasn’t really that great. America could build beautiful cars with outrageous horsepower, but we weren’t so good at going around corners. If you want a little more out of your muscle car, Speedway Motors has you covered with the G-Comp and Unser line of suspension packages.
So how do we do it? We went to the drawing board and created suspension geometry that’s more like a modern supercar than a 60’s grocery getter. A dramatic increase in camber gain through travel greatly increases the contact patch between those fat tires and the road or track. Coilovers allow fine tuning of the ride and ride height, and rack and pinion steering provides precise feedback in the curves.
We also torture test these suspensions in the real world and at the track. Team Speedway uses their fleet of race cars as rolling testbeds, subjecting all these components to stresses that are hard to duplicate anywhere else. They’re also pretty darn good at setting them up for maximum performance, and all of that knowledge goes right back into the products that we sell.
The Unser and G-Comp line are made in our own state-of-the-art machine shop. From design and manufacturing to testing and order fulfillment, we’re proud to create and support these products right here in Lincoln, Nebraska.
So what’s the difference between the G-Comp line and the Unser version? Put simply, the G-Comp is for street cars that might hit the track and the Unser is for track cars that will see some street duty.
It all started with the G-Comp. Right out of the gate, the difference in handling and performance was dramatically improved over stock. But soon, our test driver Robby Unser approached our engineering crew wanting a little more tuning potential to really push these cars to the edge. And they delivered, with the Unser package offering even more performance potential and almost infinite tuning options.
On the front suspension, the Unser gets rid of the fixed upper spring and shock mount, instead using an innovative adjustable upper mount that provides a huge range of ride height adjustability and shock length options. A tubular hoop adds stiffness to the subframe and provides a convenient place to weld to your car’s rollcage. Unser suspensions also replace the traditional forged G-Comp spindle with a fabricated upright that utilizes Covette-style hubs.
In the rear, the Unser version adds a watts link setup instead of the standard panhard bar. This allows the axle to extend through its full range of travel with no binding, that way all the power stays planted and the car remains more neutral through the turn.
In addition to the truck arm style G-Comp and Unser rear suspension options, owners of first and second-gen F-bodies (Camaro and Firebird) have a third option: the G-Comp Torque Arm setup. This version offers the advantage of being fully bolt-in, requiring no welding or floorboard modification. Also, our testing has shown this setup to have excellent forward bite and neutral handling on turn-in through corner exit.
’62-’67 Novas have notoriously primitive front suspensions. Fortunately, GM made them easy to remove. Once the hood, fenders, engine, and transmission have been removed, only a handful of bolts join the frontend to the firewall. Our G-Comp and Unser front suspension systems bolt right in to those factory locations.
GM’s revision to the Nova in 1968 updated the suspension to use a front clip similar to the F-body. While much improved over the first gen, these cars still benefit greatly from the improved G-Comp and Unser architecture.
GM’s ponycar remains hugely popular, and Speedway Motors offers our entire line of front and rear suspension for this application. From the G-Comp and Unser front to the truck arm and new bolt-in torque arm rear, we have you covered with track tested solutions for your ’67-’68 Camaro or Firebird.
GM hit a homerun with their 1970 redesign of the Camaro and Firebird, taking an already great car and making it even better with European design influences and more room for big engines and big tires. Speedway Motors offers the complete line of Unser and G-Comp suspensions for these cars as well, and we have extensively track tested all of them on our own ’70 Camaro track car.
The Universal G-Comp front suspension kit is a complete weld in front subframe assembly for converting almost any vehicle to modern-day suspension geometry and are available for 60” and 62” track widths. The 56" & 58" subframes are 29-3/4" outside of rails and use 2" x 3" x .120" wall tube. The 60" & 62" subframes are 33-3/4" outside of rails and use the same 2" x 3" tube. _ *Note: installation of these kits will require some fabrication and must be welded by a certified welder._
G-Comp: part #3502000
G-Comp and Unser suspensions are sold without shocks, springs, and brakes, allowing you to customize your order based on your application and expected driving style and use of the car.
Recommended shocks and springs for G-Comp front suspensions:
1061340CT - AFCO Street/Pro-Touring Coilover Shock (non-adjustable)
1063845PTCZ - AFCO Pro-Touring/Race Coilover Shock (single adjustable) (Modification of upper shock tower hole for adjuster knob clearance will be required upon installation)
106284001CR - Afco 8" Chrome Coilover Spring
Recommended shocks and springs for Unser front suspensions:
100205 - AFCO Max Performance/Race Coilover Shock (double adjustable)
106284001CR - Afco 8" Chrome Coilover Spring
Recommended brake kits for G-Comp front suspension:
91031958 - Speedway Deluxe Disc Brake Kit
83514010996 - Wilwood 11" GM Disc Brake Kit
8351407675 - Wilwood 12.19" GM Brake Kit
83514012271 - Wilwood 13" GM Disc Brake Kit
Recommended brake kits for Unser front suspension:
835-1408921 Wilwood 13" Brake Kit
Recommended brake kits for G-Comp and Unser rear suspension:
3501500 Unser G-Comp Style Rear Brake Kit
*Note: requires use of recommended floater-style housing.
G-Comp systems are designed with mounts for SBC/BBC Chevy engines, with available adapters (part #350025) to mount LS engines.
We have built enough G-Comp equipped cars to have a good idea of what will be necessary based on what you intend to use your car for.
Street cruiser-if you want to improve the stance and handling of your muscle car, then simply bolting on a G-Comp suspension will get you there. These systems work well all by themselves and will offer an unbelievable improvement to your cars handling, not to mention the ability to dial in the perfect stance with the adjustable coilovers.
Dual-purpose-if you intend to take your car to the next level and want to spend some time on the track, we recommend a rollcage. Not only will this make the car safer, it will also stiffen the chassis and allow you to get the most from your G-Comp or Unser suspension.
Adjustable shocks are an excellent choice in a dual-purpose car. Not only do you have some adjustability at the track, you also have the option to easily soften the car up for around town driving.
You may also consider improving your car's oil system. G-Comp and Unser equipped cars are capable of generating significant g-forces and can cause oil slosh that can starve the pickup in the oil pan and lead to engine damage or failure. You might consider a purpose-built oil pan with baffling to keep the oil where it belongs, or an oil accumulator like an Accusump. An oil pressure warning light is also recommended to alert you of any oiling issues before it’s too late.
In general, there will be some compromises made in a dual-purpose car. Ask yourself honestly how much time you will spend on the track and how much time on the street and build the car accordingly. That rollcage will make it hard for the kids to climb in and out of the backseat. Those stiff springs that plant the car at the track will be hard to live with driving around town.
Full race-if you are building an all-out racecar for road racing or autocross, the Unser suspensions are for you. The rest of the car will need to be up to the job as well. A full cage may be required by your sanctioning body, but is also a necessity to stiffen the car and keep you safe. Don’t cut corners here, your life could depend on it.
A baffled oil pan or oil accumulator may work well on a dual purpose car, but the g-forces generated by a full race Unser equipped car will almost require a dry-sump oiling system. Our Team Speedway race cars are all equipped with dry sumps and they have eliminated any oil related engine failures.
Cars like this will benefit from big brakes with soft compound pads, big sticky tires, adjustable shocks, and aggressive clutches. They will be unforgiving on the street but competitive at the track. Amateur drivers will benefit from attending a performance driving school to learn how to take full advantage of the car’s capabilities.
Orders for G-Comp systems can be placed over our order line at 800-979-0122 or online at speedwaymotors.com. You will notice that the suspensions themselves are all made to order. Typically, all necessary components are in stock, but occasionally one of the many pieces will need to be made in our machine shop. We also do a final check of all G-Comp orders in our R&D shop, so this will add about a day to the time between order completion and shipping. Most brake and shock kits are also kept in stock and will ship along with the suspension if ordered together.
There’s a lot of information here. Have questions about what’s right for you? Give our tech line a call at 800-979-0122 and we’ll be happy to talk you through the setup that will work best for your car.