Stupid question of the day (stroker motors)

Stever89

5 Year Member
Dec 14, 2009
536
9
39
Biloxi, MS
If you didn't know, how would you know if you had a stroker motor?

I got my '89 back in December. I got it from a guy who'd only had it himself for a month or so, and he had no clue what had been done to it. He bought it from the guy that built it. Aside from tracking down the guy who built it, how would you know if a motor was a stroker?

Can you tell by ear? :idk:

Aside from pulling the motor apart, what would/could one do?

Measure the displacement? How would you do that?

Just wondering. I have yet to pull the header and starter to get the engine code. I'm guessing it's a 302, but some who have "heard" it say it could be a 351 or a stroker. I haven't been around enough stroked motors to know the way a stroker would sound compared to a stock motor.

Any input or thoughts are appreciated :)
 
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NIKwoaC

中國製造
10 Year Member
Oct 31, 2006
5,500
912
214
Chengdu Province
The only way you can tell if its a stroker motor is take a head off, rotate the engine until one of the pistons is at BDC, and measure from the block deck to the piston. If it is 3.000", you have a stock stroke 302. If its 3.500", you have a stock stroke 351". If its anything between those values, you have a stroked 302, if you get more than 3.5, you have a stroked 351.

That is simplifying, but you get the idea.

That is, of course, assuming you have zero deck pistons. If you have high compression, high dome pistons or low compression dished pistons, you need to take a measurement of piston height in relation to the block deck at TDC, and then take that measurement into consideration on the numbers I listed above.

I would call :bs: on anyone who claims they can tell a sound difference between a stock stroke and a stroker engine.
 

90lxcoupe

15 Year Member
Oct 7, 2003
3,594
351
134
kind of a longshot, but my crank has is stamped on the front with "3.33" which is the stroke. You could pull the balancer and try that.

they also have some kind of tool that can tell you the displacement of the motor i think, I though i heard them doing this at races that have a max CI limit
 

Stever89

5 Year Member
Dec 14, 2009
536
9
39
Biloxi, MS
The only way you can tell if its a stroker motor is take a head off, rotate the engine until one of the pistons is at BDC, and measure from the block deck to the piston. If it is 3.000", you have a stock stroke 302. If its 3.500", you have a stock stroke 351". If its anything between those values, you have a stroked 302, if you get more than 3.5, you have a stroked 351.

That is simplifying, but you get the idea.

That is, of course, assuming you have zero deck pistons. If you have high compression, high dome pistons or low compression dished pistons, you need to take a measurement of piston height in relation to the block deck at TDC, and then take that measurement into consideration on the numbers I listed above.

I would call :bs: on anyone who claims they can tell a sound difference between a stock stroke and a stroker engine.

Thanks for the quick reply... I found a website that expands on your explanation.

Stroker Motors Explained - Stroker Engines | FordMuscle.com

I was hoping for a quick and accurate method without pulling heads, but it's not looking good :lol:
 

Stever89

5 Year Member
Dec 14, 2009
536
9
39
Biloxi, MS
kind of a longshot, but my crank has is stamped on the front with "3.33" which is the stroke. You could pull the balancer and try that.

they also have some kind of tool that can tell you the displacement of the motor i think, I though i heard them doing this at races that have a max CI limit

Good info. Thanks, that's good to know, if I ever have to pull the balancer, I'll be looking.

I'd sure like to know what they use to check the CI limit. :)
 

90lxcoupe

15 Year Member
Oct 7, 2003
3,594
351
134
I dunno but i have heard of them doing it on drag week to make sure the small blocks are under 427ci
 

cjrpony

Member
Jan 23, 2010
439
0
17
West Michigan
or if it's an option pull the oil pan and see if the cylinder walls are notched for the rods. If they aren't there's a chance it isn't.

Or if you pull the pan, slowly turn the crank and look for numbers on the crank counterweights you can cross reference. I verified a 331 one this way once.