Which Ethanol
A driver checks whether a car can take a higher ethanol blend before filling the tank.
Proof
- 3 steps
- Brand, then model, then year
- Indexed
- Compound index on brand, model, and year
- CDN
- Directory pages served from a static cache
The problem
Higher ethanol blends such as E85 can damage engines that were not built for them. The compatibility notes are scattered through long manufacturer PDFs.
What I built
I built a phone-first lookup. The driver picks a brand, a model, and a year, then gets a compatibility result and a safety note. The dataset covers 30+ manufacturers and 50+ models, checked with AI agents and correctable from an admin panel.
How it helps businesses and services
- A driver, a fuel station, or a workshop can check a blend before it goes in the tank, instead of searching manufacturer PDFs.
- The answer is tied to brand, model, and year, because the same model name can mean a different engine.
- The result is marked as a reference, with a note to confirm it against the manufacturer.
- A wrong guideline can be corrected from the admin panel without republishing the site.
How it works
- 1
Choose a brand
The directory lists manufacturers from the indexed collection.
- 2
Choose a model
Models are filtered to that brand.
- 3
Choose a year
Year narrows to the variant whose guidance actually differs.
- 4
Read the result
The page returns compatibility and a safety disclaimer.
- 5
Correct a row
Admin tools and validation scripts update a record when a guideline was wrong.
The hard part
The same model name meant different engines
Manufacturer guidance changes by year, so a model string alone is not a safe key. A compound index on brand, model, and year makes the lookup exact. Static caching then serves the directory from the CDN instead of querying MongoDB on every browse.
Stack
Backend
Data
Frontend
App
Interface
What I owned
- Brand, model, and year lookup
- Compound index on those three fields
- Dataset of 30+ manufacturers and 50+ models, checked with AI agents
- Admin verification panel and validation scripts
- Safety disclaimer on every result