How to tell 302 from 347?

[1986GT]

What is the easiest way to tell when fully assembled in the car. I was thinking I could pull a plug and try to measure with a piece of wire or something, how long the stroke is. If so what is the 347's stroke off the top of someones head.
A buddy of mine did some dealing on craigslist and the LX he got from the deal is supposed to have a 347 in it. It has TFS twisted wedge heads a runner style TFS R intake, a currently unknown cam, LT's and dumps. I took the car out and ran it and it feels like a strong running 302 but nothing like the last 347 stroker I drove. So I want to figure out for him for sure. Thanks guys.

[Gearhead]

Stroke on a 347 is 3.40" I believe.....

[outlaw85]

Check the weight on the balancer all late model 302's are 50 oz. 331-347 strokers are 28 oz. (half the size weight and probably aftermarket balancer). Its going to be pretty impossible to check the stroke through the spark plug hole considering there's only .400 difference in the 302 and 347 stroke!

[cobra429boss]

yup what he said. Cant be for sure unless you pull the heads off it and pop off the oil pan..
If the car has a stock balencer i bet top dollar its not a stroker motor

[93RedNotch]

Listen to the motor. Its kind of tricky to tell a 302 vs a 347 but there is a diffrence.

stroker-http://www.youtube.com/watch?v=C9ccEQnxGoE

302-http://www.youtube.com/watch?v=7oF36U20j_A

[95turbocharged]

Check the weight on the balancer all late model 302's are 50 oz. 331-347 strokers are 28 oz. (half the size weight and probably aftermarket balancer). Its going to be pretty impossible to check the stroke through the spark plug hole considering there's only .400 difference in the 302 and 347 stroke!

Not to sound like an ass but, my 331 is 50 oz. But if it has smaller balancer on it then it should be a stroker. And a 347 has a depper tone that is very noticable compared to a 302.

[outlaw85]

Ok some may be 50 oz. just saying the majority will be 28oz balance when building a stroker. And telling the difference by sound wow thats a new one!

[1986GT]

I will look at the balancer. I know for a fact the balancer is aftermarket because I noticed but i don't know the weight. It should be a pretty obvious size diff right? I didn't notice anything different sound wise from any other 302. And as I stated before the power was right on par with a 302 with a good H/C/I. I am not hopeful at all that its a stroker. I think he got hosed. I am going to measure the stroke anyways too, to see for myself how it goes. Its easy enough to just try. I will post up what I find.

[93snake]

can I ask where you got the car?

[Jeff88coupe]

Well a so so built 331/347 built with 302 parts will not make much more power than a well built 302/306. As said...checking the balancer is your best start.