Corvette Racing
Duntov Motor Co


Duntov Motor Company, LLC

13906-C Denton Drive
Farmers Branch, TX 75234

Toll Free Order Line
(888) 581-3838

Phone (972) 243-3838

Fax (972) 243-3828

Sportscar Vintage Racing

Lake Forest Sportscars
Corvette Grand Sport
Duntov Vintage Racing Cars and Parts
Over the Frame Headers

We make headers for all our racecars. The configuration of our headers is specified by our engine shop, but they always involve equal length runners and at least one step up in diameter. Our headers run over the frame, not under it. We can build your headers in mild steel or stainless, and we can either paint them or plate them using the latest ceramic coating. Call before ordering, as there is more information required than we can fit into this webpage!
Free Freight

Note: Price is an estimate of the minimum cost of a set of Duntov headers. The price will depend on your choice of materials, car and engine type, etc. It is highly recommended that you bring your car to us. They fit better that way! We will give you a firm quote after we have all your information. Allow 2-3 weeks for fabrication, plus shipping time.
RE100 Duntov custom Corvette headers
Duntov Custom Corvette Headers
Est. Minimum; call for a quote
Tilton Clutch Assembly

Thanks to NASCAR, we have a great source of barely used Tilton clutch assemblies. These are all Tilton parts, and include magnesium bell housing, hydraulic throw out bearing, 7.25 inch triple disc clutch, and lightweight steel flywheel. Wear on the discs is less than .005, and everything else is within Tilton Specs. Includes new ARP flywheel bolts and all required torque specifications. The new price from Tilton for this set up is more than twice ours.
Free Freight
RE200 Tilton NASCAR clutch assembly
Barely used Tilton NASCAR Clutch Assembly
NASCAR Racing Transmissions

These transmissions cost less in the long run than M22's. We run ours two seasons between overhauls. M22's are generally good for two races at 10/10ths. These transmissions are not only durable, they are a dream to shift. The RE300 transmissions are new and come with an aluminum case. The RE310s are factory rebuilt and come with a magnesium case and an internal oil pump that circulates the oil and shoots it through the external hose directly to where it is needed most. Every internal part of these transmissions is REM treated. If you are planning on running for more than 90 minutes at 10/10ths, we recommend RE310 and the optional cooler. The shifter is included, but not the shift handle. Check out the operation in the video on the home page. Click-click. You don't even need to use the clutch.
Free Freight
NASCAR racing transmissions
RE310 Transmission with Internal Pump
New NASCAR Racing Transmission with aluminum case (no internal oil pump)
Factory REMAN NASCAR Racing Transmission with Internal Oil Pump
Transmission Oil Cooler, With High Pressure Lines & Fittings
Duntov Racing Differentials

We have been building our own racing differentials for more than 30 years. The differential plays a major role in the handling of your Corvette racecar, and we will help you specify the right differential for your car. All our racing differentials come with the best 4130 HD stub axles, REM coated gear sets and new second design Eaton carriers. You can specify either the 800 lb. preload springs with steel clutch discs, or the 400lb.preload springs and carbon fiber plates. For more information on racing Corvette differentials and their effect on handling, check out our article on the subject here.
Duntov racing differential
All our racing differential gear sets are REM coated. The REM treatment is shown before and after on the ring gear at the right. The REM treated part looks chrome plated. The physicochemical process used to achieve this finish utilizes high density, non abrasive ceramic media and vibratory finishing equipment. The process removes microscopic surface asperities that are inherent in any machining process. Nothing is added to the part’s surface.
REM coated ring and pinion gears
The new style Eaton carrier comes from the factory set up with the 400 lb. springs as shown, with carbon fiber clutch discs. We will change them out to the heavier springs and steel clutch discs at no charge.Corvette Eaton carrier

New Eaton Carrier
Corvette new style Eaton carrier
800 lb. Preload Springs
All our racing differentials are set up with our preload and backlash specifications we have learned the hard way over the years. Please select your preference for 800 or 400 lb. springs.

REM Treated Ring & Pinion • New Eaton Carrier • Choice of 800 lb. Preload Kit with Steel Clutch Discs or 400lb. Preload kit with Carbon Fiber Clutch Discs • Safety Wired ARP Ring Gear Bolts • 4130 Super-Duty Axles • Racing Set-up Specifications • HD Cast Iron Rear Cover

* MPH figures assume 1-1 4th gear and Goodyear 8 inch rear tires
2.73 Duntov Racing Differential -
27.21 MPH/1000 RPM
(Le Mans)
Clutch Pack
3.08 Duntov Racing Differential -

25.89 MPH/1000 RPM
Clutch Pack
3.36 Duntov Racing Differential -

23.73 MPH/1000 RPM
Clutch Pack
3.55 Duntov Racing Differential -

22.46 MPH/1000 RPM
Clutch Pack
3.70 Duntov Racing Differential -

21.55 MPH/1000 RPM
Clutch Pack
3.90 Duntov Racing Differential -

20.44 MPH/1000 RPM
Clutch Pack
4.11 Duntov Racing Differential -

19.4 MPH/1000 RPM
Clutch Pack
4.33 Duntov Racing Differential -

18.41 MPH/1000 RPM
Clutch Pack
4.56 Duntov Racing Differential -

17.48 MPH/1000 RPM
Clutch Pack
Differential Options

With stock untreated gears, heat will cause a drop off in performance after only 15 minutes of 10 10ths racing. With REM treated gear sets, heat induced degradation begins after about 30 minutes, even with superior synthetic gear oil. Most vintage racing sessions are less than 30 minutes, but if you are going to run enduros, you might want to consider a differential cooler. We can plumb your diff case and rear cover with dash 8 fittings if you already have the rest of the system, or you can order the complete package from us that includes a Tilton pump, Earl's radiator and the lines and fittings to hook them up.
Differential fittings options
Add for Dash 8 Fittings in Case and Rear Cover
Add for Substitution of an Aluminum Rear Cover
Rear Alternator Mount

Moving the alternator rearward is a very good idea. It takes about 7 lbs off the front axle and puts it over the rear. The alternator then runs at roughly 1/3 engine speed, which is plenty on a racecar. At the rear, it operates in a much cooler environment, extending its life. We have used this setup since 1984 with no problems whatsoever. The mount requires no welding or attachment to the frame. The entire assembly is mounted to the forward differential mount. Everything is included, including the alternator and belt. You can use your alternator as a spare. Free Freight
RD400 Corvette rear alternator mount
Alternator Rear Mount Assembly with Alternator, Pulleys and Belt
Heavy Duty Diff Cover

Since the differential cover carries the suspension loads through the leaf spring, it might be a good idea to go with this 20 lb. cover. The stock cover weighs 16. It comes with a gasket. Free Freight
RD450 heavy duty cast iron Corvette differential cover
Heavy Duty Cast Iron Differential Cover
Heavy Duty Diff Cover with Fittings for Diff Cooler

If you are adding a cooler to a differential you already have, this cover has all the fittings machined into the right places. If you order a differential from us and you order the cooler option, we machine the drain line into the case itself. Here all the fittings are in the cover. It comes with a gasket. This cover accommodates the 1963-1977 2.25 inch rear leaf spring. If you are running a later model 2.5 inch rear spring, call for pricing and availability.

Free Freight
RD460 heavy duty cast iron Corvette differential cover with cooler fittings
Heavy Duty Cast Iron Differential Cover with Cooler Fittings
Aluminum Diff Cover

Although heavy, the iron differential cover is low and almost all the way back . That makes the differential cover about the last part of your racing Corvette to replace with a lighter piece. However, this part was available from the factory for Corvette racers back in 1963, Part # 0228635. If you want to be both trick and period correct, get one of these. We sand cast these covers in 356-T6 aluminum using an original GM wooden plug. It comes with a gasket. This cover accommodates the 1963-1977 2.25 inch rear leaf spring. If you are running a later model 2.5 inch rear spring, this cover won't work.

Free Freight
RD500 356T6 Corvette aluminum differential cover
356T6 Aluminum Differential Cover
Differential Cooling Package

Your differential will last a very long time if you keep it cool, and for extended sessions you will pick up a noticeable performance boost. This is the entire system. Just mount the pump and cooler and wire the pump. Be sure to circulate the fluid before deciding you have enough lubricant. The right amount is when you have the fill hole open, the pump running and fluid is circulating back into the differential. It should be pouring out from the bottom of the fill hole, not the top.
Free Freight
Duntov Tilton Differential Cooling System
Super Duty Stub Axles

With the streetcar GM stub axles, this was the weak point in the C2/C3 driveline. With these stub axles, is no longer the case. These parts are forged 4130 chrome moly steel. Imagine all that would be wiped out if you broke one of your stock stub axles and the half shaft cleaned out everything in its path. The half shaft is the upper control arm of your rear suspension. When you break a stub axle, the tire on that side tries to lay over, causing a very unsafe moment for the driver. All our racing differentials get two of these. They come as shown with caps, clips and Grade 8 bolts.
Free Freight
RD700 Corvette car set of super duty differential stub axles
One Car Set Super Duty Differential Stub Axles
4130 Half Shafts

If you are running an engine with less than 500 HP, you are probably safe to go with good, solid 3 inch OEM half shafts. If you have any more power than that, it would be prudent to go with 4130 chrome moly half shafts. We supply these with the best Spicer U-Joints and Spicer flanges.

Free Freight
RD800 Corvette 1430 chrome moly half shaft assemblies
One Car Set 4130 Chrome Moly Half Shaft Assemblies
4130 Rear Spindle

Most racecars with as much power as we run have large diameter tubular axles. On the outboard side of our driveline, we are stuck with a 50 year old spindle support housing design that dictates an axle diameter of only 1.063 inches. The original axles handled up to 375 HP on tire patches that were 5 inches wide. With twice the power and twice the tire patch, the load on the spindles has gone up dramatically. We would not race on a stock spindle. These come with ARP 7/16th or 1/2 inch wheel studs in either the stock length (for steel wheels), or 3 inch as shown.
Free Freight

Please specify either stock length or 3 inch wheel studs as shown.
4130 chrome moly Corvette rear spindle
One 4130 Chrome Moly Spindle with 7/16ths wheel studs
Stud Length
One 4130 Chrome Moly Spindle with 1/2 inch wheel studs
Stud Length
ARP Wheel Studs

ARP is the best name in fasteners for racing. We sell these studs in two lengths and two diameters.

Please specify wheel stud length
ARP wheel studs
One Car Set ARP 7/16ths Wheel Studs (20 studs)
Stud Length
One Car Set ARP 1/2 inch Wheel Studs (20 studs)
Stud Length
Aluminum Front Differential Mount

These are solid aluminum bushings that replace the stock rubber bushing. It's really important to keep your differential perfectly still!
RD950 Corvette aluminum crossmember bushings
Aluminum Front Diff Mount

Duntov Motor Company is the exclusive licensee for the continued production of the authentic original Corvette Grand Sport.  Duntov Motor Company is the exclusive licensee for the manufacturing and distribution of the updated street version of this famous car. We service what we sell. We also restore and service 1963-1982 Corvette race, street and performance cars using original and replacement parts including front and rear suspension, brake calipers, brake rotors, brake pads, both J-56 and stock brake caliper pistons, and Corvette stainless steel parking brake parts. We offer the finest original U.S. built Corvette spindles and GM stub axles, along with remanufactured Corvette differentials for both street and race cars. We build both new and rebuilt Corvette trailing arm assemblies for 1965-1982 Corvettes, and offer Corvette street and racing springs and both steel and composite leaf springs in a wide selection of spring rates. Check out our Corvette parts section for shocks, sway bars, upper and lower A-arms, Corvette ball joints, tie rod ends, pitman arms, idler arms, shocks and U-joints.

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