Plastigauge

Plastigauge for Porsche

Plastigauge ® is a precision clearance gauge for the measurement of clearance (separation) between fitted surfaces. It is particularly useful for measuring clearances in split bearings or in situations where a feeler gauge cannot be inserted, and is widely used on Porsche engine builds and inspections.

A Quick Look at Plastigauge

Plastigauge information on this page is based on details supplied by the manufacturer or distributor, plus any OE references provided with the parts.

Choosing the Right Fit for Your Porsche

Where Plastigauge is listed for Porsche, use the supplied model coverage and OE references to confirm suitability. Check details that commonly affect fitment such as model year, engine variant, and the clearance range printed on the pack so you are measuring within the correct window.

• Used during Porsche engine builds to confirm bearing clearances quickly and validate machining or measurement work.
• Helps catch clearance issues before first start-up, reducing the risk of bearing problems from incorrect tolerances.
• Common risks when clearances are wrong include bearing knock, low oil pressure, spun bearings, and premature wear.
• Misleading results usually come from dirty journals, incorrect torque procedure, mixing shells, or using Plastigauge on oiled surfaces or outside its range.
• Use Plastigauge as a cross-check alongside micrometers and bore gauges, not as a replacement for proper measuring tools.
• Work clean and dry, torque to spec, and record results so you can compare to Porsche workshop data.

Browse by Category

If you already know the area you are working on, start with the category and then filter by Porsche model. Where real-world symptoms and typical reasons to replace are provided, use them to keep the wording grounded.

Engine Rebuild Parts — Typically used during a Porsche engine rebuild or major internal repair, where you may also be checking clearances with Plastigauge while renewing gaskets, bearings, chains, guides, and other wear items to avoid repeat strip-downs.

• Before committing to a rebuild, carry out compression and leak-down tests, borescope inspection, and check the oil/filter for debris.
• When the engine is apart, replace hard-to-access wear items “while you’re in there” to improve long-term reliability.

Engine Bearings / Shells — Closely related to Plastigauge use, as shell bearings rely on correct oil clearance for pressure and durability; often changed during rebuilds, after low oil pressure events, or when wear is suspected from mileage, contamination, or track use.

• Always inspect crank journals, measure clearances, and address root causes such as oil pump condition, debris, or overheating during bearing work.
• Remember that low oil pressure can appear before audible knock, so don’t rely on noise alone as an indicator.

Connecting Rod — Connecting rods and their big-end bearings are another common area checked with Plastigauge; rods are replaced or upgraded when bent, cracked, out of spec, or when aiming for higher RPM and cylinder pressures.

• Re-use rods only if they pass detailed measurement and reconditioning, including bolts and small-end bushes where appropriate.
• Over-rev, oil starvation, or detonation are typical root causes of rod damage, so ensure these are diagnosed and corrected.

Crankshaft & Parts — Crankshafts and associated parts depend on precise bearing clearances and journal condition; Plastigauge helps verify that clearances are within spec after machining or polishing.

• Crankshafts may be reused if they measure within specification and pass crack testing; otherwise rework or replacement is required.
• During crank work, it is normal to renew bearings and thrust elements to restore oil pressure and protect against repeat failure.

Explore Plastigauge at Design911

View the current Plastigauge range for Porsche at Design911, then filter by model and category to narrow down to the right parts and measuring ranges for your engine project.