Yet another 408 stroker recipe thread

[rt-man]

So, I'm looking ahead to 2024 and have decided to shelve the idea of putting a 400/440 in the SSP cuz too many other things need to be changed out for a SB-BB swap. I'm thinking stroking the 360LA that's in it will give me what I'm looking for: a lower rpm, stump puller type 408, budget street build. High RPM isn't in the cards. It's pulling a heavy B-body, looking for the low-end torque of a big(ger) block without a vacuum-killing camshaft. But I have some restrictions that the speed group will get aggravated with: staying with existing 340 HP manifolds, existing cast iron heads (already ported for larger int/exh valves), existing Edelbrock Performer dual plane intake. Yes, I know I'll be giving up top end HP but am good with it.

So "budget' means what/who's stroker kit, correct cam for the parts mix, probably a bigger carb (currently 600cfm Holley/Summit knockoff), machining the bottom end for clearance. What am I missing?

**Currently a rebuilt 904 behind the combo now, but I have a SB 727 in the parts bin that will get rebuilt and go behind the stroker, get the driveshaft cut down, etc.

Thanks in advance for the recommendations. Street car only, pulling a '73 B-body.

 

[rt-man]

Bores are .040 over, current cam is a Hughes grind (flat tappet hydraulic)(I think its this but can't put my hands on the cam card right now):
SB HYD FLAT TAPPET CAM 224/228 -111ºLSA

LOBE LIFT .345"/.353"

3.55:1 gearing

 

[rmchrgr]

I'm always for more cubes but that combo of parts seems pretty mild, might not be worth the expense of going the stroker route? 360s are inherently stump pullers. Think about what they originally came in - big, heavy trucks and vans and wagons that were used for plowing or towing.

If the stock crank and rods are good and don't need a lot of work ($$) perhaps consider getting some 'better' stock stroke pistons for better squeeze and the 367" mighht perform the same or slightly better than a 408". That cam will likely 'act bigger' with less stroke. You want port velocity and cylinder pressure, the extra volume might reduce those factors.

OTOH, if the stock rotating assembly needs a bunch of machine work ($$) like grinding, re-sizing, balancing, etc., the 408" is often the same cost and you have new parts so at that point it's kind of a no-brainer. You can usually get kits that are internally balanced too which makes the damper and flex plate easier.

Either choice will be a low RPM deal but the 360 will rev a bit more.

 

[Dodge Bros]

I’d keep the 904 if your going the LA route. We ran a 72 b body with a 904 with a B&M shift kit behind a turbochargered 318 that made more torque than most big block cars. No reason I can think of to use a 727.

I don’t think you’d regret going the 408 over a 360.

 

[dvw]

I second the idea to stay with the 904. It's plenty strong enough. It's lighter and uses less HP. There is a factory 2.74 low gear set available as well. It will give you the overall 1st gear ratio equivalent to a 3.91 used with a stock ratio 2.45.
Doug

 

[rt-man]

Thanks you for all the thoughtful responses. I'll be going back and forth on this. While it hustles (I forgot to mention a RR torque converter, I don't recall what stall), it is pulling about 3900 lbs with me in it. And the two B-bodies I had before this one both had 440s.

Oh, to have big-block penis envy