FAQ
TL;DR: In 2023 LPG cuts Polish running costs by 45 % versus petrol [PolishUOKiK 2023]; "There is nothing like a large naturally aspirated engine" [Elektroda, andrzej lukaszewicz, #17546907]. For ≤70 k PLN you can gas Honda Accord 2.4 201 HP, Volvo S80 V6, or Chrysler 300C 3.6. Why it matters: You avoid fragile downsized turbos while keeping brisk 0-100 km/h below 8 s.
Quick Facts
• Honda Accord VIII 2.4: 201 HP, 7.9 s 0-100, 8.9 l/100 km petrol [Honda Spec 2014]
• BRC Sequent 32 LPG kit (4-cyl DI/PI blend): approx. 5 500 PLN installed [ACSA 2024]
• Valve clearance check Accord K24Z3: every 40 000 km, 90 min labour [Honda Service]
• Polish fuel Jan 2024: LPG 3.2 PLN/L; 95 RON 6.5 PLN/L [e-Petrol 2024]
• Average LPG gives 10 % power loss vs petrol, fuel bill −40 % [AC Autogas 2023]
1. Which 2014-on cars fit 70 k PLN, ≥200 HP, and like LPG?
Honda Accord 2.4 201 HP, Volvo S60/S80 2.5 T 231 HP, Chrysler 300C/Lancia Thema 3.6 286 HP, Ford Mondeo Mk5 2.0 EcoBoost 240 HP (needs DI kit), and Lexus IS 250 208 HP meet the brief. All have proven valve seats; only EcoBoost needs manifold swap for durability [Elektroda, multiple posts #17529475 #17527198 #17543415 #17568874].
2. Why do forum members prefer naturally-aspirated over direct-injection turbos for LPG?
Indirect injection keeps petrol injectors cool during LPG operation and avoids costly high-pressure pumps. Turbo DI heads run hotter, risking valve recession and coked intake valves [AC Autogas 2023]. "Most modern DI engines have problems on gasoline alone" [Elektroda, andrzej lukaszewicz, #17546907].
3. How fast and stable is a large SUV like Mazda CX-9 at 150 km/h?
At 190 km/h top speed, the 2-ton CX-9 feels soft-suspended and needs more steering corrections than a sedan; reviewers note 0.80 g skid-pad versus Accord’s 0.87 g [Car&Driver 2015]. Driver Nix prefers sedans for highways [Elektroda, Nix, post #17529789]
4. Is the Mazda 3.7 V6 engine good for LPG?
Yes. The Ford-derived MZI V6 has chain-driven cams, wide valve seats and no direct injection. Many run 200 000 km on sequential LPG with only 0.2 mm shim adjustments needed every 120 000 km [Elektroda, Nix, #17527184; GreenCarReports].
5. What hidden cost exists in Volvo S80 AWD?
Early P3 S80 bevel gears wear; rebuild costs 2 000–3 000 PLN though parts are common [Elektroda, paszczakq, post #17551401] Acura Legend’s SH-AWD replacement exceeds 8 000 PLN and parts ship from the US [Elektroda, Nix, post #17547272]
6. How do I LPG-convert a direct-injection EcoBoost safely?
Use a dual-fuel DPI system that adds 15 % petrol for injector cooling. Maintain OE spray angles. Follow this 3-step retrofit:
- Install cast-iron exhaust manifold PN BM5G-9430-AE.
- Fit Stag 400 DPI ECU with six Keihin injectors.
- Program petrol addition map above 4 000 rpm [Elektroda, paszczakq #17570490; Stag Manual 2023].
7. What edge-case failure should I watch in Ford 2.0 EcoBoost?
The stock aluminium manifold cracks near the turbo flange around 90 000 km, leading to over-boost and turbine damage [Elektroda, paszczakq, post #17572832] Cast-iron retrofit removes the risk.
8. Are BMW/Audi/Mercedes totally off-limits?
The OP excluded them. However, US-import BMW F10 with N52 motors accept LPG well [Elektroda, piotrek0007q, post #17556853] If brand neutrality matters, skip them.
9. What maintenance keeps a Honda Accord 2.4 healthy on LPG?
Change oil every 12 000 km, adjust valves at 40 000 km, replace LPG filters at 20 000 km, and monitor injector trims monthly. Users report 350 000 km without head work [HondaService; Elektrode, tida1, #18434496].
10. Does LPG reduce engine power?
Expect about 3-5 % lower peak power and 1 s slower 0-100 km/h, negligible in 200 HP cars [AC Autogas 2023].
11. How much will I save annually driving 20 000 km on LPG?
At 8.9 l/100 km petrol vs 11 l/100 km LPG, fuel spend drops from 11 570 PLN to 7 040 PLN, saving 4 530 PLN per year [e-Petrol 2024].
12. Why did the thread opener choose the Accord?
It met power, year, and LPG compatibility while avoiding premium German brands. Final post: "Accord 2.4 bought – closing" [Elektroda, tida1, post #18434496]