QA1

QA1 coilovers and suspension for muscle cars, classic trucks and street cars: Pro Coil front coilover systems, rear coilover conversions, Proma Star and Mod Series shocks, coilover springs, control arms and sway bars. Pro Coil systems here cost $911 to $1,304, and coilover springs start at $106. Many listings show the spring rate, and all show the QA1 part number.

Who QA1 is

QA1 makes suspension, steering and chassis parts for muscle cars, classic trucks, street cars and race cars. Its mission, in its own words, is to "build high quality, affordable solutions." QA1 is part of a family of performance brands with Detroit Speed, Speedtech Performance and Proforged, and it also makes rod ends and shock absorbers for industrial and OEM customers.

QA1 is best known for adjustable coilover shocks and bolt-in coilover systems that replace the factory springs and shocks on older American cars and trucks. Its shocks can be rebuilt by authorized rebuild centers, which matters if you plan to keep the car for years.

QA1 product lines on our store

We list 274 QA1 products. Check each listing to see whether it is a single shock or spring, a pair or a complete system.

LineWhat it isListingsOur price
Pro Coil front coilover systemsBolt-in front coilovers, single (GS) or double (GD) adjustable27$911 to $1,304
Rear Pro Coil conversionsRear coilover kits that replace factory coil springs and shocks13$1,013 to $1,340
Proma Star coilovers and systemsAdjustable coilover shocks and struts, single or double, plus systems27$280 to $2,124
Mod Series4-way adjustable shocks with QuickTune valve packs, plus kits13$126 to $2,732
Stocker Star shocksAdjustable shocks that bolt in where the stock shock goes43$232 to $393
Coilover springsHigh-Travel and Pro coilover springs by rate67$106 to $146
Full conversions and lowering kitsC10, F-100 and Mopar coilover conversions; Ford truck and GM truck lowering kits14$3,139 to $6,829
Arms, bars and chassisControl arms, sway bars, trailing arms, ball joints, rod ends, bracesAbout 70$86 to $1,990

How to choose QA1 coilovers

Pro Coil vs a full coilover conversion

A Pro Coil system is the bolt-in route. QA1 says its front GM Pro Coil kits use a conical spring that sits in the factory upper spring pocket on the frame and onto the QA1 coilover shock at the bottom, so you keep your stock control arms and frame. Our front Pro Coil systems cost $911 to $1,304. Rear Pro Coil conversions do the same job at the back for $1,013 to $1,340.

The C10, F-100 and Mopar conversion systems are full packages with the parts to convert a classic truck or car to coilovers front to rear. They cost $3,198 to $6,829 on our store. Pick one if you are rebuilding the whole suspension, not just swapping springs.

Single vs double adjustable

QA1 single adjustable shocks have 18 clicks, and one knob changes compression and rebound together. Double adjustable shocks have 18 clicks of rebound and 18 of compression, set separately, for 324 combinations. QA1 says a single adjustable is fine for a street car or a casual track car, and double adjustable is for racing or owners who want to fine-tune. On our store the step from a GS single to a GD double Pro Coil system is $911 to $1,168.

Proma Star, Stocker Star and Mod Series

  • Stocker Star: an adjustable shock that mounts in the stock location. It is the simplest upgrade when you want to keep your springs.
  • Proma Star: QA1's adjustable coilover shocks and struts, used in many of its systems.
  • Mod Series: QA1 calls this a 4-way adjustable shock with QuickTune valve packs, made for drag race, pro-touring and track cars. It is the most expensive line.

Picking a spring rate

Most QA1 coilover springs on our store list the rate in pounds per inch, often in the part number, such as the 7HT400B at 400 lbs/in. Our spring rate calculator helps you pick a rate for your car's weight before you order.

Fitment coverage

Many QA1 listings show only a part number, but about 80 name a make or model in the description:

Make named in listingListingsExamples on our store
Ford and Mercury391964 to 1973 Mustang, 1965 to 1979 F-100, 1993 to 2004 Ford models, 2021 to 2025 Ford trucks
Chevrolet and GMC371963 to 1987 C10, 1960s and 70s GM cars, 1999 to 2006 GM trucks
Dodge and Plymouth91960s Mopar engine mounts and conversions, 1982 to 2004 Dodge shocks
Pontiac, Buick and Oldsmobile71964 to 1972 GM A-body rear conversions

For more ways to set up these vehicles, see our C10 lowering kits, Mustang coilovers and lowering springs, Camaro coilovers and F-150 lowering kits.

QA1 vs other brands we carry

QA1 vs Detroit Speed. Detroit Speed is in the same family of brands. It leans toward complete, premium chassis upgrades, while QA1 focuses on adjustable shocks and bolt-in coilover systems at a lower price.

QA1 vs Classic Performance. Classic Performance sells lowering and suspension parts for classic trucks and cars, at $83 to $2,364 on our store. It is a good fit for a budget drop; QA1 is the pick for adjustable damping.

Install notes

  • Set the ride height first, then get an alignment.
  • Start shock settings in the middle of the range and adjust from there.
  • Full conversions may need welding or a shop, depending on the kit.
  • Warranty terms are set by each brand.

Popular picks

Related guides

Sources

QA1 FAQ

What is a QA1 Pro Coil system?
It is a bolt-in front coilover kit for classic and muscle cars and trucks. QA1 says its GM front kits use a conical spring that fits the factory upper spring pocket and sits on a QA1 coilover shock, so you keep the stock arms.
What is the difference between QA1 single and double adjustable shocks?
Single adjustable shocks have 18 clicks on one knob that changes compression and rebound together. Double adjustable shocks have 18 clicks each for rebound and compression, set separately, for 324 combinations.
Do I need double adjustable QA1 coilovers for the street?
Usually not. QA1 says a single adjustable shock works fine for a street car or casual track car, and double adjustable is for racing or fine-tuning.
Are QA1 shocks rebuildable?
Yes. QA1 says its drag racing and street performance shocks can be rebuilt by authorized rebuild centers in the U.S.
How do I pick a QA1 coilover spring rate?
Most of our QA1 spring listings show the rate in pounds per inch. Use your car's corner weight and our spring rate calculator to choose a rate before you order.
How much do QA1 coilovers cost?
On our store, QA1 Pro Coil front systems cost $911 to $1,304, rear conversions $1,013 to $1,340, and full C10, F-100 and Mopar conversions $3,198 to $6,829.