435 BBC VS 422 SBC

[ProStreetLuvr]

Hello guys I just finished reading Hot Rod Magazine's "HUFF & PUFF" article in "Horsepower Handbook: Big Block Chevy and "How To Build Big Inch Small Block Chevys".

A few weeks ago at Summit Racing Motorsports Park a fellow I had spoken to on another Forum a few years ago was running Mid 11's which was off pace for his GTX. (He runs a Pump Gas 6-71 Supercharged 446 CID Mopar BB with a Air to Water Intercooler, his times are normally in the low 10's with this simple setup & a Heavy car.)

Both the SBC and the BBC are potent engines as witnesssed by Rob Mixx's 700+ HP E-85 383 SBC and Hot Rod's 825 HP 454 BBC.

A SBC has 1 advantage over the BBC it is lower in weight.

Here are the 2 options Desired output 580-725 HP/520-650 LB FT TQ:

I) A +.040 overbore forged pistons 8.25-8.75:1 CR, 454 block, forged 3.766 inch crank, forged 6.385 rods, a HYD Roller Cam 114 degrees LSA, Edelbrock's New Aluminum heads, an 8-71 Blower underdriven to deliver 6-8.5 PSI, twin E-85 830 DPs.

II) A +.040 overbore forged pistons 8.25-8.75:1 CR, Dart Iron Eagle or World Motown block, forged 5.85-6.0 rods, a HYD Roller Cam 114 degrees LSA, AFR 220 CC ported heads,an 8-71 Blower underdriven to deliver 6-8.5 PSI, twin E-85 830 DPs.

I know option 2 will most likely have the higher price tag but will be able to grow a couple of times.

Which option would you choose for a short wheel based light car like a Chevy Vega Coupe, Datsun 510 Sedan, or Ford Anglia/Thames?

[Michael]

This is a tough one to answer.

I am a huge fan of big-cube small blocks (I actually have a stock GM 350cid small block in the garage that I'd like to bore and stroke to a 396cid one day) and as you said, the small block has the advantage over the big block in that it saves weight. Additionally, small block parts are also cheaper (and much easier) to come by than their big block counterparts.

However, the big block does have a few advantages that the small block will almost never match. Big block cylinder heads, for one, are one area that the small block can't hold a candle to; the splayed valve design of the standard big block heads facilitates much better airflow and a much more efficient combustion chamber design than the straight angled valves of standard small block heads. And while splayed valve heads are available for small blocks, they are INCREDIBLY expensive and typically require custom fabricated intake and exhaust manifolds.

The other (obvious) advantage to the big block is they are designed and engineered to BE high capacity engines. In other words, they have the necessary "meat". A typical big cube small block requires a lot of machining/grinding/clearencing to ensure everything fits (ie connecting rods clear the sides of the block as the crank rotates)

And that's not to mention, of course, that big blocks are just very cool (and are actually becoming more and more rare... at least from what I've seen).

However, given your specific horsepower targets and vehicle application, I would suggest sticking with the whole "minimum weight" theme and go with option 2. Both the Eagle or World Products small blocks are designed and engineered to run large cubic inches, so you won't have to deal with the considerable machining and grinding to get to the target displacement needed; producing the desired horsepower levels won't be difficult either, although I have a feeling the big block will probably facilitate future power increases better than the small block. And given the size/type of vehicle(s) you're considering, shoehorning a small block will prove MUCH easier than trying to stuff a big block between the fenders.

Of course, the idea (and the resulting sight) of a blown big block powered Vega or Datsun 510 would be pretty cool, and very tempting indeed...

[ProStreetLuvr]

In my previous post I neglected to mention the SBC would have a 4.165 bore with a 3.875 inch crank for a CID of 422, this is similar to a 400 SBC with a +.040 overbore and a 1/8 inch stroker crank.

The thoughts of an 8-71 Roots Blower with dual 830 E-85 DPs and a Blower N2O plate sticking through the hood of any of these cars should make the Import crowd's blood run cold. :violent: :evil::laugh::shocked:

I read an article called "Huff & Puff" where a 454 made 825 HP with an 8-71 Blower (12PSI) then they hit it with a Progressive Time Based 175 HP N2O system(196 HP at one point in the RPMs) actual output hit 1007 HP at 6800 RPM.

[vinces427bb]

In my previous post I neglected to mention the SBC would have a 4.165 bore with a 3.875 inch crank for a CID of 422, this is similar to a 400 SBC with a +.040 overbore and a 1/8 inch stroker crank.

The thoughts of an 8-71 Roots Blower with dual 830 E-85 DPs and a Blower N2O plate sticking through the hood of any of these cars should make the Import crowd's blood run cold. :violent: :evil::laugh::shocked:

I read an article called "Huff & Puff" where a 454 made 825 HP with an 8-71 Blower (12PSI) then they hit it with a Progressive Time Based 175 HP N2O system(196 HP at one point in the RPMs) actual output hit 1007 HP at 6800 RPM.

i would have voted for the BBC as it would be more impressive visually

i know this is an older post
but i think either would be great in your truck.
did you get this project rolling???