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Offenhauser 39-53 Flathead Ford 4-Ring Pistons, 3.75 Stroke/3.248 Bore

Specs
Sold in Quantity:
Set
Piston Diameter:
3.248
Stroke:
3.75
Piston Weight:
468
Piston Style:
Flat Top
Dome Height:
1.729
Piston Material:
Cast Aluminum
Garage Sale:
No
Offenhauser 39-53 Flathead Ford 4-Ring Pistons, 3.75 Stroke/3.248 Bore
Offenhauser 39-53 Flathead Ford 4-Ring Pistons, 3.75 Stroke/3.248 Bore
Offenhauser 39-53 Flathead Ford 4-Ring Pistons, 3.75 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.

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

  • 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

Item Details

3.248" bore, 3.75" stroke

Customer Reviews

Rated 5 out of 5 by 1 reviewers.
RATING BREAKDOWN
1 reviews
5 Stars
1
4 Stars
0
3 Stars
0
2 Stars
0
1 Star
0
RECOMMEND THIS PRODUCT:

Pete's Rod Shop
Rochester, OH
Product Rating

Specs are all "right on"

April 25, 2010
I have not installed the pistons yet, but they all mic'ed nicely.
Yes, I recommend this product.
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Was this review helpful? 0 0

Page 1 of 1

Product Q&A

3 questions : 3 answers

wrist pins is it center of or shift ?

1 answers
henri
September 15, 2013

wrist pins is it center of or shift ?

Answers

September 16, 2013
Jason
The wrist-pins in these pistons are centered, so there is NO "left" or "right" to them.

Are the pistons flat top or dome and how tall is the dome? And how much do the piston and wrist pin weigh?

1 answers
Fredric
Sweden
June 11, 2013

Are the pistons flat top or dome and how tall is the dome? And how much do the piston and wrist pin weigh?

Answers

June 12, 2013
Jason
This offenhauser piston has a dome shape and a 1.729" compression height. The piston and pin weighs 468 grams

what is the wall clearance that is recommended for these pistons?

1 answers
Mackman
Houston,TX
April 25, 2011

what is the wall clearance that is recommended for these pistons?

Answers

April 27, 2011
Jason
.0015” - .002” minimum
Page 1 of 1

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1939-53 Flathead Ford V8 4-Ring Pistons, 3-3/4 Stroke, .060 Over
(Part #91015900)
                        

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.

Sizing based on original 3.188" bore. Fits .060" overbore size and 3.75" stroke crank. Sold as a set of 8.

  • 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
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Each piston set includes:

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(Part #56042620)
                        

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

Instructions (PDF) 

 

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