McAfee SECURE sites help keep you safe from identity theft, credit card fraud, spyware, spam, viruses and online scams
Phone

800.979.0122

Bill Smith
Founder, 1929-2014
Speedy Bill
Since 1952
Speedway Motors Logo
America's Oldest Speed Shop ®

Search

Offenhauser 39-53 Flathead Ford 4-Ring Pistons, 4.00 Stroke/3.248 Bore

SAME DAY SHIPPING! Order within the next 8 hours 23 minutes and receive same day shipping

Specs
Sold in Quantity:
Set
Piston Diameter:
3.248
Stroke:
4.00
Piston Style:
Flat Top
Piston Material:
Cast Aluminum
Garage Sale:
No
Offenhauser 39-53 Flathead Ford 4-Ring Pistons, 4.00 Stroke/3.248 Bore

Click image to enlarge

Please NOTE the following about this product:

  • This item is sold as a set.

Details

Reviews

Q & A

What's in the Box

Original Flathead pistons used four rings, were somewhat round, had questionable wrist pins and locks and were made of cast iron. These pressure-cast aluminum pistons share the four-ring design, but are cam ground and use modern steel wrist pins and real snap rings. They’re a great upgrade when rebuilding your 1939-1953 flathead Ford or Mercury V8 engine.

  • Original 4-ring design
  • Pressure cast aluminum construction provides great strength and durability
  • Precision cam ground
  • Modern steel wrist pins
  • Snap ring style retainer clips

The original bore size was 3.188", which makes these .060" oversize. Sold in sets of eight.

Item Details

3.248" bore, 4.00" stroke

Customer Reviews

This product has no reviews.

Product Q&A

2 questions : 2 answers

What is the diameter of the piston axle?

1 answers
henri
france
June 17, 2013

What is the diameter of the piston axle?

Answers

June 17, 2013
Jason
The wrist pin diameter is .748"

My question is if the pistons for 4" stroke fit a Mercury 255, 1951

1 answers
Leif
Vendelso, Sweden
August 11, 2011

My question is if the pistons for 4" stroke fit a Mercury 255, 1951

Answers

August 12, 2011
John
These pistons are specific to the Flathead Ford V8 and will not work on the Mercury motors. Pin location in the piston is different between the Ford and Mercury and will create dramatic problems. You may want to check with Egge Machine for availability of pistons for your Mercury motor.
Page 1 of 1

You may also be interested in:

1939-53 Flathead Ford V8 4-Ring Pistons, 4 Inch Stroke, .060 Over
(Part #91015902)
                        

Original flathead pistons used four rings, were somewhat round, had questionable wrist pins and locks and were made of cast iron. These pressure-cast aluminum pistons share the four-ring design, but are cam ground and use modern steel wrist pins and real snap rings. They’re a great upgrade when rebuilding your 1939-1953 flathead Ford or Mercury V8 engine.

  • Original 4-ring design
  • Pressure cast aluminum construction provides great strength and durability
  • Precision cam ground
  • Modern steel wrist pins
  • Snap ring style retainer clips

Sizing based on original 3.188" bore. Fits .060" overbore size and 4" stroke crank. Sold as a set of 8.

Arias Forged Flathead Ford Pistons, 4.00 Stroke
(Part #14528080)
                        

If you are going to spend the time and money to build the flathead of your dreams, you just as well spring for Arias forged pistons. Arias forgings work great with nitrous and up to 10 psi on blown engines. They come as a set of eight and include wrist pins, locks and piston rings. They are a three ring design and work with the stock 7" rod length. Stock flathead bore size was 3.188"

Each piston set includes:

  • (8) Forged Aluminum Pistons
  • (8) Wrist Pins w/ Locks
  • (8) Cast Ring Sets
Rings for Offenhauser 4-Ring Flathead Ford Pistons, 3.248 bore
(Part #56042620)
                        

The original bore size was 3.188", which makes these .060" oversize.

Instructions (PDF) 

 

Flathead Ford 4 Ring Set, 3.188 Bore, +.060 Oversize
(Part #91015904)
                        

Fits 3.188" bore Speedway Custom 4 Ring Pistons for Flathead V8.  Set of 8.  Cast Iron top and 2nd groove rings.

+.060" oversize.  Oversizes based off original 3.188" bore size.

Ford Flathead V8 Builders Handbook
(Part #91085211)
                        This book covers every facet of your Flathead Ford V-8. Rebuilding? Get one of these books! 200 images. 154 pages.