C i d #

[trike84]

I have a 59 AB that has a bore of 3 3/8 by 4 1/8 stroke, what the displacment. I used a C I D caculator on line, it said 226 CI. the piston are domed. 3 3/8 with 3/16 LC (low crown) measured stroke from outside edge of piston to top of bore. piston tops out at the the top of cylinder.

[Neal]

295 cu.inch. I figured that out without an online calculator but I think I am closer than what you got. The dome of the piston doesn't matter as long as the dome is the same at both ends of the stroke.

Neal

[Bored&Stroked]

I always heard that LC meant 'Long Crank' - as all the old Jahn's pistons were marked?

Question: Is the edge of the piston just flush with the deck? It should be, or the combination of parts may be incorrect.

Have a picture?

[ironman123]

295.22448 or just 295 CI. Neal has the answer.

[51 MERC-CT]

Sounds like what we used to run in stock cars back in the 50's (295.2 ci )

[Ol' Ron]

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I built one of these for my friend Ron Horrell's 35 PU about 15 years ago and it's still running. The engine has a set of 4 ring stock typr pistons that are fir with .002" clearance. I've never seen another set like this and I can't remember who made them. Crank is an old Merc offset ground and 21A rods, L-100, C-4 trams.

[trike84]

thanks for the Information, and the clairification on the LC stamping. my father built it to run in a 32 roadster he was going to build. I'm going to build it, So I will be asking a lot of questions. By the way, I knew it wasn't 226 C I.

[flatjack9]

I always took LC to mean low crown.

[rotorwrench]

It goes to show, you can't believe every thing you find on the internet!

[trike84]

well that is what I thought LC stode for low crown, or is it, some clairification on these stampings from the OL barners would be apreciated.

[trike84]

I did some digging on the H.A.M.B. blog and found thread from Jet mek. l c= low crown, the piston pin is located 3/16 higher in the piston than a stock 3 3/4 stroke piston. this must be to allow for the dome and not require head work.

[V8COOPMAN]

Any time a piston pin is located higher on a replacement piston, the DIFFERENCE in height generally amounts to 1/2 of the INCREASE in stroke length.....IF the rod length remains unchanged.

Hoping this doesn't resurrect a firestorm from yesterday. DD

[Pete]

Originally Posted by flatjack9

I always took LC to mean low crown.

Correct.

The dimensions given in the original question were always referred to as a "3/8 x 3/8" engine. That was derived from a 3 3/8 bore and a 3/8 over stock Ford stroke.
It was also called a "296" from rounding the math off to the next highest number. A common practice.

[Ol' Ron]

LC= Low compression.

[trike84]

What would be a ballpark HP rating? speed equip as follows Fenton heads and intake,2 97's, headers. Cam is an unknown, lift is approx. 1/4 to 5/16 (eyeballed) Harmon-collins 1400 dist.

[trike84]

Ol Ron , why would it have 3/16 stamped in it if it just mean low comp.

[Ol' Ron]

I'm not sure where the term LC was first used on pistons to denote the stroke. However back in the 50's when the 4" Merc crank came out the pistons were marked 1/8 LC. I asked what that ment and was told Low compression because if used with a stock crank it would be 1/8 down the cylinder. Never gave it much thought until today.

[Walt Dupont--Me.]

Back in the 50's I built an engine with a 4-1/8 crank and used 1/8 LC pistons instead 3/16LC, the piston came up 1/16 over the top, I used 2 head gaskets for awhile and later had the heads domed. Used to drag at Sanford Maine. Used an Alumquest cam, 3 carbs, Lincoln Zef dist. Wish I still had the engine. Walt

[scooder]

Originally Posted by trike84

What would be a ballpark HP rating? speed equip as follows Fenton heads and intake,2 97's, headers. Cam is an unknown, lift is approx. 1/4 to 5/16 (eyeballed) Harmon-collins 1400 dist.

That's quite a wild guess at cam lift. 1/4" = .250" 5/16" = .312" less than stock lift - more than stock lift.
Cams are normally marked on the front face or around the part that the timing gear bolts on. Harmon and collins cams are marked Luke the latter, in tiny writing. Some cams have intentional mis markings to fool nosey folk at the pits.

As for power, it's anybody's guess. I will quote a Bell Auto Parts advert from April 1952. Balanced stroker assembly. 133 hp for your stock Ford with no other special equipment. It was a 4" Merc crank with 3 5/16" or 3 3/8" bore 275 or 286 ci respectively. Your Ford heads will give you 7.8:1 compression and your engine will develop approximately 133 hp. Same engine will produce a smooth dependable 170 hp with addition of a 3/4 cam, dual manifold and dual exhaust system.
$184.
That's the add. Interesting they don't say a difference in power between the 3 5/16 or 3 3/8".
Take from that what you will.
Your cam needs to be known really.
Remember with a flathead the numbers on paper meen a whole lot less than the feel in your pants.
Martin.

[trike84]

thanks scooder, Ill pull the timing cover and gear and check.