Racing Epoxy for Engine and Metal Repairs
Racing epoxy is a two-part repair material used on compatible engine and metal surfaces. Depending on the formula, two-part epoxy putty may be used to fill, shape, or repair intake manifolds, cylinder-head intake ports, heads, blocks, and other properly prepared surfaces. Before choosing a product, compare service-temperature limits, cure time, fluid resistance, machinability, and approved applications. Not every metal repair epoxy is suitable for structural cracks, exhaust components, or exposure to gasoline, oil, or E85. For related repair products, shop racing adhesives, racing gaskets and seals, or review Moroso A&B Epoxy.
Shop Behrent’s for Racing Epoxy
Shop racing epoxy for compatible engine and metal repair applications. Compare cure time, temperature limits, fluid resistance, machinability, and approved surfaces before choosing a formula.
Item Number: EDE9290
$50.95
Usually Ships In 3-5 Business Days
How to Choose Racing Epoxy
Match the epoxy to the surface, service conditions, and type of repair before comparing cure time or workability.
| Product Type | Best For | What to Verify |
|---|---|---|
| Two-part epoxy putty | Filling, shaping, and building up compatible surfaces | Mixing ratio, working time, cure time, approved surfaces, and machinability |
| Metal repair epoxy | Approved repairs on clean metal components | Surface preparation, temperature range, fluid resistance, and whether the repair is structural or cosmetic |
| Engine block repair epoxy | Formula-approved engine block, head, or lifter-gallery repairs | Pressure exposure, temperature, oil or fuel contact, and whether welding or machining is required instead |
| High-temperature epoxy putty | Repairs exposed to elevated operating temperatures | Maximum service temperature, cure requirements, and material compatibility |
| A/B epoxy | General two-part repair work where a moldable or spreadable formula is specified | Mix ratio, pot life, cure schedule, sanding or drilling capability, and fluid resistance |
What Else to Check Before Ordering
The strongest repair comes from matching the product to the job rather than assuming all epoxies perform the same way.
- Approved surfaces: Confirm the epoxy is intended for the metal or component you’re repairing
- Temperature range: Check the service limit for the actual application
- Fluid exposure: Verify compatibility with oil, gasoline, coolant, E85, or other fluids
- Cure time: Compare working time, handling time, full cure, and return-to-service timing
- Machinability: Check whether the product can be sanded, drilled, or tapped after curing
- Repair type: Structural, pressurized, or safety-critical damage may require welding, machining, or replacement instead
How to Use Two-Part Epoxy Putty
Use the product instructions for the exact mix ratio, working time, and cure schedule.
- Confirm that the product is suitable for the surface, temperature, fluids, and type of repair.
- Remove paint, grease, oil, loose corrosion, and other contaminants.
- Roughen the surface if the manufacturer recommends it.
- Mix parts A and B completely in the specified ratio.
- Apply and shape the epoxy within its stated working time.
- Allow it to cure for the required time and temperature.
- Sand, drill, tap, prime, or paint only when the instructions permit it.
- Wait for full cure before exposing the repair to heat, pressure, or fluids.
Important: Don’t treat racing epoxy as a replacement for welding or mechanical repair on structural, pressurized, or safety-critical components.
Frequently Asked Questions About Racing Epoxy
Can you paint over epoxy resin on a race car?
Some fully cured epoxies can be painted, but compatibility varies by product. Let the repair cure completely, then sand and clean it as directed. Use a compatible primer and paint system, and follow both the epoxy and paint manufacturers’ instructions before coating the repair.
Can you apply epoxy over rust?
Not over loose rust, scale, paint, oil, or contamination. Remove unstable material first and leave a clean, solid surface. Only apply epoxy over residual rust when the manufacturer specifically approves that use. Never use standard A/B epoxy as a rust converter.
What’s the difference between A/B epoxy putty and paste?
Putty has a thicker, moldable consistency that works well for shaping and filling gaps. Paste is generally more spreadable and can be better for coating or filling shallower areas. Both use separate components that must be mixed thoroughly in the specified proportion.
What can racing epoxy be used to repair on an engine?
Applications depend on the formula. Some brands are formulated for intake manifolds, cylinder-head intake ports, heads, blocks, lifter-gallery crevices, and installing filter screens. Not every engine block repair epoxy can replace welding or machining for serious cracks or structural damage.
How long does A/B epoxy take to cure?
Cure time varies by product and ambient temperature. Some A&B epoxy can harden in 60 minutes at 75°F, but don’t apply that timing to every formula. Check the individual product instructions for working time, full cure, and return-to-service timing.
Is racing epoxy resistant to gasoline, oil, and E85?
It depends on the product. For example, Moroso states that its A&B Epoxy is unaffected by oils and gasoline but is not recommended for E85. Don’t assume the same fluid resistance applies to every epoxy unless the product documentation confirms it.