Building my first motor!!

Djstorm100 · Nov 30, 2007

Well I'm going to start building my first motor soon. Its stock spec 302 (not bored or stroked) I always have been told the longer the rods the better.

Stock rod length is what?

I know 331 stocker uses 5.4 rods and new crank. Could I use 5.4 rods and get shorter (height wise) pistion?

Also what cc are the stock heads? I'm trying to determine what compression I'll be at with a given CC of combusion chamber

I know you have to take end account the deck height? ( maybe wrong here) Deck height is the distance form center of crank to top of the cylinder (not including the headgasket) correct??

I know you have to take encount the headgasket for sure.

5spd GT · Nov 30, 2007

8.2 is the factory deck height, which can vary by a few thousandths either way.

You are correct, deck height is from the crankshaft centerline to the top of the bore.

A 331 typically has a 5.4" rod, but there are a couple companies that make a 5.315" rod.

Stock 302 rod is 5.090".

A 331 kit comes with a new crank (3.25"), new rods (5.4 or 5.315"), and a new piston (1.175" or 1.250").

A longer rod is good in a few cases, but not the "end all, tell all."

It can increase dwell time (get a cam spec'ed for it), increases the rod/stroke ratio, and usually makes for a lighter piston, since it needs to be shortened to fit in the deck height parameters.

If you want more info, just out the 1st link in my signature about the differences.

Djstorm100 · Nov 30, 2007

reason being I was going to get a short block locally that has stock spec rods and forged pistions. I wanted to have the compression at 9 or so or 8.5:1 for boosting purposes.

The guys has build motors before and is anal but the fact that I didnt build it worries me (paranoid)

its 300 for it all oil pan, block, stock style roller lifters, rods, ect ect just not dizzy, intake manifold, and heads

PUNISHER RACING · Nov 30, 2007

you could make a long rod 302 with a 5.4 rod and stock crank and special pistons they love to rev. the stock heads are 61 cc and when put on a cammed 331 usually make about 350 horse and 400 torque at their flywheel.

5spd GT · Nov 30, 2007

I would not do a long rod 306.

Very cost inefficient if you are looking for extra power.

Building my first motor!!

Djstorm100

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5spd GT

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Djstorm100

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PUNISHER RACING

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5spd GT

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Building my first motor!!

Djstorm100

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"the 5.0 owns all"

Djstorm100

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5spd GT

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