Big - Small Block or Small - Big Block Question

I am currently running a Dart Block based 406 SBC 594 hp/540 ft. lbs. tq. For my boat, I think it is the best way to go. Very balanced setup!!

The small block strokers make some impressive numbers, but they have limiting factors esp. in marine applications!!!
 
You can't compare apples and oranges. If you had a 454 big block vs a 454 small block and both had same compression ratio setups and equally equipped etc., etc., and were in the same boat, the small block should win the race hands down every time because it's much lighter in weight than the big block. There are so many facets to this argument that you could go on forever, but I remember back in the 70's when Smokey Yunick built a 208 cubic inch small block Chevy for Indy that had something like 900 horsepower, and they don't lift the throttle at Indy for 3 hours. Anyone that would argue a small block won't hold up to endurance hasn't turned on the TV on Sunday's for the last 30 years.
 
So much depends on the geometry of the engines. Two engines with the same bore, stroke, rod length, compression and airflow numbers would theoretically generate the same power curve. In that case, the lighter engine should win out every time.

The LS series engines are a whole different kettle of fish. Not only are they more like a "mid-block" in terms of displacement, most of them are aluminum as well. Personally, I'd love to see more development go into marinizing these engines.

It's are pretty amazing if you think about it. The basic small block is now 54 years old and has grown from 265 to over 400 cubic inches, and the big block is over 40 and has grown from 396 to over 500 cubic inches. If you count aftermarket blocks, the numbers go even further. Granted, there have been many "Generations" of these engines, but the basic architecture has to have been pretty d@mn good.
 
I am currently running a Dart Block based 406 SBC 594 hp/540 ft. lbs. tq. For my boat, I think it is the best way to go. Very balanced setup!!

The small block strokers make some impressive numbers, but they have limiting factors esp. in marine applications!!!



I am working with the Furniture Row Nascar Team right now and I am building 2- 434ci small blocks using the Dart raised deck and raised cam block. I am using their SB-2 heads right off their car engine. I also am putting fuel injection right on their Intake manifold also. The engine will 9.1 compression to run on pump gas.
 
I do agree Sean BUT it seems i need more HP and less TQ in my boat to spin my surface drives more rpm

It happens try changing your cam profile a little bit and see what happens... I am no engine builder so you would have to get with one of the guys from the board here to get an exacting definition from one!!!!!!
 
Easy Sean.....

small block high revver low torque
big block low revver high torque
Offshore boat torque is good

Easy Sean, you know my latest build is with twin smallblocks! LOL

Agreed, cubes are always better, but I am trying something different this time. That is lighter boat / good power to weight ratio. 76% of the power we had in our Top Gun, but less that 50% of the weight. Plus less power drag going from #3SSM's & tranmissions to Bravo XRE's. Lower CG too.

Barry
 
So I say to my boat, "Boat: are you gonna lose any weight? You are one heavy sombinch."

Boat says "No, I am not. This is the way that Bobby made me. Are you gonna tell that lake to calm down?"

I say "No. She doesn't calm down."

And the Boat says: "Good. Build bigger big blocks."

There you have it.
 
Did someone say "Big Block"?

How about one of Sonny Leonard's 932 cube monsters... Or maybe two of them... :D

http://www.sonnysracingengines.com/sar932.html

The biggest problem I've found with the huge cuin stuff is everything is one off, no parts to be had at all. And it's almost impossible to find the stuff with cooling in the blocks.

I think about 800 cuin is the biggest out there with cooling systems and you're still looking at Big Chief heads etc.
 
Smallblocks... The efficiency of the new ls motors is great. We are within 1 hp on the dyno wih the motors we are running. They have not missed a beat.

Complete AVR LS7 engine,headers,dual cooler bellhousing,clutch,fnr offset transmission,chromoly steel engine mounts = less wt / then HP. :sifone:

pat W
 

Attachments

  • x1 027.jpg
    x1 027.jpg
    75.8 KB · Views: 25
It happens try changing your cam profile a little bit and see what happens... I am no engine builder so you would have to get with one of the guys from the board here to get an exacting definition from one!!!!!!


Yup i want to do that it is in the works as we type!!:)
 
Smallblocks... The efficiency of the new ls motors is great. We are within 1 hp on the dyno wih the motors we are running. They have not missed a beat.

The LS platform is truly awesome! :drool5: How much "work" has been done to those things?
 
We have done some work to them but they we are running them between 5000 and 7300 rpm 90% of the time. The stock cam makes it idle real well, we lost that right away. Nothing like a bang stick to wake up an engine. We are trying to keep the engines as stock as possible. They are really good out of the box.

pat W
 

Attachments

  • P3160016.JPG
    P3160016.JPG
    73.1 KB · Views: 18
  • P2240014.JPG
    P2240014.JPG
    72.3 KB · Views: 14
  • P9130008.JPG
    P9130008.JPG
    77.5 KB · Views: 17
Back
Top