Fixing 243 Head Problems on Your 2020 Chevrolet Corvette

How to Fix 243 Head Issues

This guide addresses potential issues with 243 heads in your 2020 Chevrolet Corvette. The 243 heads are a component of the engine. Many owners consider swapping or modifying these heads to improve horsepower and engine performance. However, this may lead to problems if done improperly. "Personally, I think you should do it all at once and avoid the tune fee repetition cost," advises one owner regarding modifications (source). This guide will cover potential issues, diagnosis, and fixes based on owner experiences.

Symptoms

Symptoms related to 243 head issues in your Corvette can manifest in different ways. The most prominent ones are PTV (piston-to-valve) clearance issues and stalling. PTV clearance problems often arise after modifications, where the valves and pistons might come into contact due to incorrect installation or aggressive camshaft profiles. This can lead to engine damage if not addressed promptly.

Another reported symptom is stalling. This can occur if the engine isn't tuned correctly after the 243 heads or other modifications. The car may stall at idle or during low-speed operation, making it difficult to drive. This issue is often related to an improper air-fuel mixture, which can be exacerbated by modifications that change the engine's airflow characteristics.

Dynamic compression ratio (DCR) can also be affected by changes to the cylinder heads. An incorrect DCR can cause issues like detonation or pre-ignition, which can damage the engine. These problems are often subtle at first but can lead to significant issues over time. It’s crucial to monitor engine performance after a head swap.

These symptoms may not always appear immediately after the work is done. Some issues might take some time to become apparent. It's important to monitor your engine and listen for any unusual noises or performance issues.

Most Likely Cause

The primary cause of issues related to 243 heads in your 2020 Chevrolet Corvette is improper engine modification, specifically when swapping or modifying the heads without proper tuning. "I don't think you'd be disappointed with quality porting from any reputable source whether you had 241s or 243s," says one owner (source). This suggests that the quality and expertise of the person doing the work play a huge role. If the modifications aren't done correctly, you could run into PTV clearance issues or DCR problems.

A key factor is the tuning after the swap. The engine's computer needs to be calibrated to the new airflow and valve timing characteristics of the 243 heads. Without proper tuning, the engine may run lean or rich, leading to stalling, poor performance, and potential engine damage.

Another cause is the installation of other aftermarket parts along with the 243 heads. This can further complicate the tuning process and make it more difficult to achieve optimal engine performance.

How to Diagnose

Diagnosing 243 head-related issues involves a few key steps to pinpoint the problem. You'll need tools to accurately assess the engine's performance.

1. Visual Inspection: Start by visually inspecting the engine for any obvious signs of damage, such as leaks or broken components. Check the cylinder heads for any cracks or signs of overheating. Look for anything that might indicate a problem with the installation.

2. Compression Test: Perform a compression test on each cylinder to check for any signs of compression loss. Low compression in one or more cylinders can indicate a problem with the cylinder heads, such as a valve that isn't sealing properly.

   • Tools Needed: Compression tester.
   • Steps: Remove the spark plugs, insert the compression tester into each cylinder, and crank the engine to measure the compression.

3. Leak-Down Test: If you find low compression in one or more cylinders, perform a leak-down test to determine the source of the leak. This test involves pressurizing the cylinder with compressed air and listening for leaks coming from the exhaust, intake, or crankcase.

   • Tools Needed: Leak-down tester, compressed air source.
   • Steps: Bring the cylinder to top dead center (TDC) on the compression stroke, apply compressed air to the cylinder, and listen for leaks.

4. OBD-II Scan: Use an OBD-II scanner to check for any trouble codes stored in the engine's computer. Codes like P0300 (random misfire), P0171 (system too lean), or P0174 (system too rich) can indicate a problem with the cylinder heads or the engine's tuning.

   • Tools Needed: OBD-II scanner.
   • Steps: Plug the scanner into the OBD-II port and read any stored trouble codes.

5. Data Logging: If you suspect a tuning issue, use a data logger to monitor the engine's performance in real-time. This can help you identify problems with the air-fuel ratio, ignition timing, or other parameters that could be causing the stalling or performance issues.

   • Tools Needed: Data logger, laptop computer.
   • Steps: Connect the data logger to the OBD-II port and use the laptop to monitor engine parameters while driving.

Step-by-Step Fix

Based on what has worked for other owners, here's a step-by-step guide to address common issues related to 243 heads on your 2020 Chevrolet Corvette.

1. Verify the Tune: Ensure that the engine is properly tuned for the 243 heads and any other modifications that have been made. This may involve taking the car to a reputable tuner who specializes in Corvettes. As one owner shared: "I took them to a shop and had em 'gone over' when he put my BTR springs in" (source). This highlights the importance of professional assistance.

2. Check PTV Clearance: If you suspect PTV clearance issues, you'll need to remove the cylinder heads and inspect the pistons and valves for any signs of contact. If there is contact, you may need to install smaller valves or fly-cut the pistons.

   • Remove cylinder heads
   • Visually inspect pistons and valves
   • Address contact issues (smaller valves, fly-cutting)

3. Inspect Valve Springs: After installing new heads it is critical to make sure that the valve springs are within proper spec. It’s possible a weaker spring will affect performance of the engine.

   • Measure valve spring pressure
   • Replace worn springs

4. Check for Leaks: Inspect the cylinder head gaskets for any signs of leaks. If you find a leak, replace the gasket with a new one. Make sure the head bolts are torqued to the proper specifications.

   • Visually inspect head gaskets
   • Replace if leaking
   • Torque head bolts correctly

5. Replace Worn Components: Replace any worn or damaged components, such as valve springs, retainers, or valve seals. This will help ensure that the cylinder heads are functioning properly. "Oil/Filter change after a few hundred miles post 243 head, headers and TSP low lift cam swap" (source). It is good to replace oil and oil filters after major engine modifications.

6. Reassemble and Test: Once you've addressed any issues, reassemble the engine and test it to make sure it's running properly. Monitor the engine's performance closely and make any necessary adjustments to the tuning.

7. Consider Upgrading Components: If you’re running into issues, it might be that the rest of the engine can't keep up with the new heads. Upgrading to a Melling oil pump and throttle body might be necessary to make sure that your vehicle performs the best.

Parts and Tools Needed

• Cylinder head gaskets (Part number will vary based on manufacturer)
• Head bolts (Part number will vary based on manufacturer)
• Valve springs (if needed)
• Retainers (if needed)
• Valve seals (if needed)
• Compression tester
• Leak-down tester
• OBD-II scanner
• Data logger
• Torque wrench
• Socket set
• Wrenches

Real Owner Costs

The cost of addressing 243 head-related issues can vary widely depending on the nature of the problem and whether you choose to do the work yourself or take it to a shop.

DIY Costs:

• Cylinder head gaskets: $50 - $150
• Head bolts: $50 - $100
• Valve springs: $100 - $300
• Retainers: $50 - $100
• Valve seals: $20 - $50
• Tools (if needed): $100 - $500

Total DIY Cost: $370 - $1200

Shop Costs:

• Labor: $500 - $2000 (depending on the complexity of the work)
• Parts: $370 - $1200 (same as DIY)

Total Shop Cost: $870 - $3200

One owner mentioned getting their heads "gone over" at a shop when installing BTR springs (source). This suggests that the cost can vary depending on the extent of the work being done.

It's always a good idea to get quotes from multiple shops before deciding on one. This will help ensure that you're getting a fair price for the work.

Prevention

Preventing issues with 243 heads in your 2020 Chevrolet Corvette primarily involves careful planning and execution during any modifications.

• Proper Tuning: Always ensure that the engine is properly tuned after installing 243 heads or any other modifications that affect the engine's airflow or valve timing.

• Professional Installation: If you're not comfortable doing the work yourself, consider taking the car to a reputable shop that specializes in Corvettes. As one owner suggested, seeking out a "reputable source" for porting or other work is essential (source).

• Regular Maintenance: Perform regular maintenance on the engine, such as oil changes and spark plug replacements. This will help keep the engine running smoothly and prevent problems from developing.

• Monitor Engine Performance: Keep a close eye on the engine's performance after any modifications. If you notice any unusual noises, vibrations, or performance issues, address them promptly.

What Owners Say

Real experiences from CHEVROLET owners:

Owner Experiences

"Quote: Originally Posted by Prop Joe I just looked and they are out of stock on the Brawlers. Take Smitty's injectors (if he finds them), you'll need them at some point." — Midwayman (source)

"Quote: Originally Posted by Stingroo I'm pretty good about that. I don't think you'd be disappointed with quality porting from any reputable source whether you had 241s or 243s." — carl418 (source)

"I don't think you'd be disappointed with quality porting from any reputable source whether you had 241s or 243s. I'm going 243 because I bought them so cheap I couldn't say no, and I don't need to down the car and pull my stock stuff off since my C5 is my daily driver." — carl418 (source)

Lessons Learned

⚠️ "The new one has a 3.9" hole vs the 4.1" on the LS9. I'll be a bit more careful with my right foot till the tune is done and I can be trusted with the power." — JumboShrimp (source)

Pro Tips from Owners

💡 "Personally, I think you should do it all at once and avoid the tune fee repetition cost. You might want to check with Tony, tell him your plan and see if he'll work with you if you throw a set of heads/headers on later." — Midwayman (source)

💡 "I took them to a shop and had em 'gone over' when he put my BTR springs in. I got a little frisky and lifted one (even with ARP studs) - blew out both frost plugs (if you ever have to change them make SURE you use the metric size - not generic 1-1/4")." — JumboShrimp (source)

FAQ

Q: How long does it take to fix 243 head-related issues?

A: The time it takes to fix 243 head-related issues can vary depending on the nature of the problem and whether you choose to do the work yourself or take it to a shop. Simple issues, such as replacing a leaky cylinder head gasket, may only take a few hours. More complex issues, such as addressing PTV clearance problems or tuning issues, can take several days.

Q: Can I drive with 243 head-related issues?

A: It depends on the nature of the problem. If the issue is relatively minor, such as a small leak, you may be able to drive the car for a short period of time. However, if the issue is more serious, such as PTV clearance problems or significant stalling, it's best to avoid driving the car until the problem is resolved. Driving with a serious issue can cause further damage to the engine.

Q: Is this a common issue on the 2020 Chevrolet Corvette?

A: Issues related to 243 heads are not necessarily common on the 2020 Chevrolet Corvette in stock condition. They are more likely to occur after modifications have been made to the engine, such as swapping or porting the cylinder heads. The frequency of these issues depends heavily on the quality of the work done and the engine tuning.

Q: DIY vs mechanic - what's recommended?

A: Whether to DIY or take it to a mechanic depends on your mechanical skills and experience. If you have experience working on engines and are comfortable with tasks such as removing and installing cylinder heads, you may be able to address the issues yourself. However, if you're not comfortable with these tasks, it's best to take the car to a reputable shop. Proper tuning is often necessary, and that requires specialized knowledge and equipment.