We have been drag racers and we’ve done our fair share of road racing in Chevy High Performance. Drag racers are not road racers and road racers are not drag racers, and that’s that. With that said, what’s the difference between suspension systems for drag racers and road racers? Plenty.
Drag racers are engineered to shift weight to the rear wheels upon launch to get good traction and move in a straight line as quickly as possible down the 1320 and through the traps. Road racers are more about holding the road at speed through the twisties and onto the straights as quickly as possible. Both forms of racing are about quickness and elapsed times, but that’s about the only thing they have, suspension setup wise, in common.
We’re working with a first-gen Nova hardtop being built at LP Racing in Ontario, California, as a period gasser. It is one thing to have a lot of power for drag racing and quite another to get that power to the pavement for a successful launch and the desired elapsed time. We’ve opted for a 9-inch rear axle from Currie Enterprises coupled with coilover shocks and ladder bars from Speedway Motors. LP Racing is handling the rest.
This isn’t a simple bolt-on affair, but instead consists of readymade steel chassis parts that have to be precisely located and then welded in. LP Racing is up to the task with a terrific in-house fabrication staff ready to show us how it is done. CHP
1. Our classic, first-gen drag Nova is getting this brute-tested tough Currie 9-inch housing and differential set up for a ladder bar installed up its backside.
2. This Currie 9-inch housing can withstand 400-450 horsepower without breaking a sweat. But it’s up to you to decide what gearing and components go inside. The minimums you’ll want are 31-spline axles and a limited-slip differential engineered to get power to both tires without breaking. If you have any questions, Currie’s customer service staff can help you make the right decisions.
3. With our Currie 9-inch, we opted for these huge, large-bearing drum brakes, which are perfect for this particular application. They arrive completely assembled and ready to go. Currie offers several brake package options, both drum and disc.
4. These Speedway Motors coilover shocks are tuned for drag racing, which allow for proper weight shift when it’s time to get it on.
5. The first order of business is to get the rearend set up for installation. This is known as the “mock-up” phase where everything is bolted together for a fitment check to see how the parts mesh together.
6. The Speedway Motors coilover shocks are bolted in place to check for alignment and fit.
7. This is where fabrication skills are paramount. LP Racing has tack-welded the upper shock brackets to the custom-fabricated crossbrace so the coilover is perfectly vertical. These guys pass the fit check.
8. A crossbrace for the front ladder bar brackets has to be fabricated to install between the Nova’s subframe connectors. Any qualified chassis shop should be able to do this for you if you don’t feel up for it. Of course, if you live in the Los Angeles area, LP Racing can take care of your fabrication and installation needs.
9. The adjustable, front ladder bar brackets are located and squared to the crossbrace.
10. LP Racing then TIG-welded the ladder bar brackets to the crossbrace.
11. The subframe connectors are measured as to where to weld in the LP Racing custom-made crossbrace.
12. Once the subframe connectors have been measured for the crossbrace, the surfaces are cleaned up with a disc sander to achieve a good, clean weld.
13. The LP Racing crossbrace has been welded in place. The Speedway Motors ladder bars are nice pieces sporting adjustable Heim joints and great strength. These fully adjustable brackets allow for proper geometry when it’s time to tune at the track. It is recommended to start off adjusting from the middle position.
14. The Speedway Motors ladder bars are fully adjustable to where you can perform axle alignment (white arrow) and pinion angle (red arrow) adjustments via these groovy Heim joints.
15. All the brackets, braces, etc., have been tack-welded during the mock-up phase. We tack weld because we’re seeking a perfect fit and if adjustments are needed we don’t want to have to cut a complete, finish weld apart.
16. The final phase of the Currie/Speedway drag suspension installation is this Panhard bar, which keeps the rear axle centered, and is fully adjustable.
17. LP Racing has mocked up the Panhard bar and welded in all of the brackets. The Panhard bar is installed, followed by a rear axle alignment check.
18. Of course, we’re not going to keep these underpinnings in raw steel. We’re going to tear it all down and get everything treated with either powdercoat or paint. Then, it’s time to go drag racing.
19. A footnote to this installation is the mandatory subframe connectors. When you’re building a classic unibody Nova or Camaro, even for street use, subframe connectors take the flex out of the chassis for a solid ride. We’ve seen builders go to extremes with crossbracing and torque boxes. Yeah, it’s that important.
20. LP Racing does really terrific fabrication work. Check out this bulletproof transmission crossmember fabricated in-house.
21. With all the mock-up work out of the way and LP Racing’s close attention to precision fitment, final welding is performed all over the chassis.
22. We’re really digging these cool Firestone drag slicks from Coker Tire. They are the perfect accent for a period gasser.
23. Our Currie/Speedway rear drag suspension is complete. Keep in mind you need good fabrication and math skills to do this. Otherwise, it is best left to the professionals.
Photos by Jim Smart