Estimated horsepower - stroked 351w?

MintyFresh

Member
Nov 2, 2019
19
7
13
Denver
I just picked up a project car in the form of a 68 coupe. Some previous owner swapped in a 351w that I'm told is stroked to 387. That probably means it has 302 pistons, stock rods, and a 3.85 crank.

Assuming that's accurate, what's a general ballpark for horsepower?

Cheers!
 
  • Sponsors (?)


There's so much involved in making horsepower that anything you find on the internet is likely to be nothing more than a wild guess. Having said that, if it's a stock 351W (quite likely unless you have positive proof of what's in the engine) with 9:1 compression iron heads and a mild cam, it's likely making about 275- 300 flywheel horsepower. If it has a decent intake and 600 cfm carb, maybe 20 hp more. Headers add another 5-10 ponies. Nice aluminum heads add maybe 35-40 hp as long as they have good springs and rockers. It's not hard to yank 400hp out of a 351W in mild tune, but cylinder heads and intake are the key.
 
There's so much involved in making horsepower that anything you find on the internet is likely to be nothing more than a wild guess. Having said that, if it's a stock 351W (quite likely unless you have positive proof of what's in the engine) with 9:1 compression iron heads and a mild cam, it's likely making about 275- 300 flywheel horsepower. If it has a decent intake and 600 cfm carb, maybe 20 hp more. Headers add another 5-10 ponies. Nice aluminum heads add maybe 35-40 hp as long as they have good springs and rockers. It's not hard to yank 400hp out of a 351W in mild tune, but cylinder heads and intake are the key.

That's exactly what I was looking for - thanks a ton! I'm about to take the engine and transmission out so I can start the exterior restoration. I'll learn more about the block, head, and carb during that process. So far driving it feels like it's in the 300+ range. It's a total kick to drive. One of the previous owners put some work into the engine with the stroker kit, but also added traction bars 11" rear wheels, and a few other street mods that make it seem like he was going for a drag race setup.
 
:worthlesb

--and--

If you're going to make that motor, 'MintyFresh', what kind of budget are you looking at? What's the end goal? SOTP street warrior, weekend cruiser, or spend some time at the track?

Welcome to :SN:
 
--and--

If you're going to make that motor, 'MintyFresh', what kind of budget are you looking at? What's the end goal? SOTP street warrior, weekend cruiser, or spend some time at the track?

We're doing a full rotisserie restoration (not concourse). I'm not looking to put anything else into the drive train. It's all in good shape and just needs to be cleaned and tuned up. It's really just a question of wanting to know what I have in terms of performance since it's not the original engine. The seller didn't know anything about the car's history.
 
IMG_0795.jpg
 
  • Like
  • Hell Yeah!
Reactions: 2 users