400 sb with 3" stroke?

rayfin · 08-03-2009, 09:41 PM

I always wondered what a 400 sbc with a 283 crank would run like. Anyone ever tried this? I know the 302 sbc (4" x 3") was a hard runner. Just curious.

Mark Markow · 08-04-2009, 05:04 PM

my modified motor is a 4.155 bore and 2.970 stroke. it runs good, but expect a high reving piece. peak power was at 9200rpm.

rayfin · 08-12-2009, 08:41 AM

Any videos on youtube?

masracing · 08-15-2009, 04:33 AM

If you have a good set of heads on it, it should work very well. I am by no means an expert but I know they have found with the comp motors big bore and short stroke will make more horsepower/cubic inch. It stands to reason bigger piston means you can run bigger valves without shrouding. You have a larger surface area on top of the piston which when you think of the laws of hydraulics would generate more force on the piston for the same cylinder pressure. The catch to it is having a good enough flowing cylinder head to efficiently fill that large bore at high RPM.

Just my understanding of it so take it for what its worth.

B.J. Masiello

rayfin · 08-25-2009, 01:07 PM

Thank you for the feedback guys.

Bill Baer · 10-26-2009, 08:22 PM

Quote:

Originally Posted by masracing

If you have a good set of heads on it, it should work very well. I am by no means an expert but I know they have found with the comp motors big bore and short stroke will make more horsepower/cubic inch. It stands to reason bigger piston means you can run bigger valves without shrouding. You have a larger surface area on top of the piston which when you think of the laws of hydraulics would generate more force on the piston for the same cylinder pressure. The catch to it is having a good enough flowing cylinder head to efficiently fill that large bore at high RPM.

Just my understanding of it so take it for what its worth.

B.J. Masiello

Mr. Masiello pretty much right on target but if your bracket racing especially if your using an auto trans, a longer stroke/bigger motor will make the same or more power, more torque and at a lower RPM range and it's torque that moves the car.
It could be fun if you had a tunnel ram, Titanium valves and a five speed! (At least until you break a couple of valve springs!)

08-03-2009, 09:41 PM	#1
rayfin Member Join Date: Mar 2009 Location: sioux city Posts: 134 Likes: 1 Liked 0 Times in 0 Posts	400 sb with 3" stroke? I always wondered what a 400 sbc with a 283 crank would run like. Anyone ever tried this? I know the 302 sbc (4" x 3") was a hard runner. Just curious.

08-04-2009, 05:04 PM	#2
Mark Markow Senior Member Join Date: Apr 2008 Location: east hartford ct. Posts: 539 Likes: 1 Liked 9 Times in 3 Posts	Re: 400 sb with 3" stroke? my modified motor is a 4.155 bore and 2.970 stroke. it runs good, but expect a high reving piece. peak power was at 9200rpm.

08-12-2009, 08:41 AM	#3
rayfin Member Join Date: Mar 2009 Location: sioux city Posts: 134 Likes: 1 Liked 0 Times in 0 Posts	Re: 400 sb with 3" stroke? Any videos on youtube?

08-15-2009, 04:33 AM	#4
masracing Junior Member Join Date: Nov 2008 Posts: 60 Likes: 0 Liked 0 Times in 0 Posts	Re: 400 sb with 3" stroke? If you have a good set of heads on it, it should work very well. I am by no means an expert but I know they have found with the comp motors big bore and short stroke will make more horsepower/cubic inch. It stands to reason bigger piston means you can run bigger valves without shrouding. You have a larger surface area on top of the piston which when you think of the laws of hydraulics would generate more force on the piston for the same cylinder pressure. The catch to it is having a good enough flowing cylinder head to efficiently fill that large bore at high RPM. Just my understanding of it so take it for what its worth. B.J. Masiello

08-25-2009, 01:07 PM	#5
rayfin Member Join Date: Mar 2009 Location: sioux city Posts: 134 Likes: 1 Liked 0 Times in 0 Posts	Re: 400 sb with 3" stroke? Thank you for the feedback guys.