Considering you can make 400hp with a set of lowly $250 used 461 Casting Camel Hump/C2 Heads on a Roller Block with a ZZ4 or LT4 Hotcam and a $300 carb....a horribly easy 400hp at that.

1. Ditch the Factory TPI Manifold it won't flow the air needed
It was made to produce torque... you need air for the top end..
where the factory TPI manifold strangles the life out of the motor.
There won't be any lack of Torque with a good cam selection...
and if you go 383 you sure won't be lacking torque.

2. Get Heads that Breathe... just about anything aftermarket from
with 185 to 200cc's of runner and proper induction up top
will get you over the 400hp barrier.

My number 1 player would be my manifold choice... hands down..
because that block can make 400hp with very plain jane
junkyard heads and nothing special cams.

 

First off, here's something I always advise when questions like yours pop up on this and other Forums.

When wanting to increase the power of an engine while, at the same time, keeping the engine streetable and a daily driver, you should expect 1.1 to 1.2 HP per cubic inch. Select your parts accordingly.

Using that tried and true expectation will show that, when doing the math, more cubic inches will result in more power. Comparing apples to apples a 383 will make more power than a 350/355; a 406 will make more power than a 383, etc. That is assuming that the engines will be comparably built.

In search of more power, it actually boils down to the four 'C's:

Cubic Inches
Cylinder Heads
Camshaft
Compression

That's the basic order to attack the issue.

Here's where your budget HAS to be taken into account. You may not be in a position to buy and have machined a 400 block, a block that will put you above 400 cubic inches; but then again you might be in a position to do that.

Best recommendations would be to go with all forged internals - crank, rods and pistons. Now, of course you could run a cast crank or stock rods with better bolts or even hypoeutectic (sp?) pistons, but BEST would be all forged aftermarket parts. So here again, budget rears it's ugly head.

Best course of action would be to sit down and decide on just much money you have to spend on the project. That dollar figure will guide you in your parts selection.

Since there are so many companies making good parts for our engines, if you want to see actual part numbers and prices, go to a site like CNCMOTORSPORTS.COM and they'll be posted there.

For me, selecting an engine for a L98 type car, I'd do this:

400 block bored .030; tanked, honed, decked, align honed, Oliver four bolt main caps on the center three.

Forged EAGLE or SCAT crank and rods with SRP forged pistons.

Standard tension ring set; Clevite bearings

AFR 195cc Eliminator heads with 7/16" rocker studs and springs capable of handling more that .600 valve lift. Watch the combustion chamber size in their offerings so you don't give up any compression.

1.6 or even 1.7 roller rocker arms; I like Scorpions, NON-SELF ALIGNING

.080" wall, one piece, hardened TrickFlow pushrods of the correct length

CompCams Hydraulic roller camshaft- 230/236 @ .050, XFI series

TPIS Mini-Ram

BBK 58mm Throttle body

Injectors determined by the person re-programming the PROM

Higher stall converter if you're running an A/T; 2500 to 3000 stall with a trans cooler.

If your budget can handle it: Full length 3/4" headers, Random Tech Cat, free flowing mufflers (this is a personal preference thing and depends on how much sound you can live with). Lower ratio rear end gears.

Those are just my choices, others probably have theirs. A lot of it really depends on how much money you have to spend on the project.

Jake

 

Three words, Sonny crate motor.

Or a 383 with solid roller cam and high rise single-plane intake w/holley 750. Hood scoop optional.

 

He wants to make 400 HP, not 800.

 

I run a stock short block with Ported heads, ZZ9 cam, Miniram and a 4K stall torque convertor. The combo goes right around mid 11's at 119 MPH.

I have driven Superram setup and they feel real good on the street, very Torquey. A Miniram flys at the track and is ok on the street.

Vic

 

No budget, does not compute

Good Heads alone, by themselves, cost $1900-$2300, it adds up quick

 

Hey Vic, very strong combo there; will we see it again in 1 1/2 weeks??

 

The new 892ci Sonny crate motor pumps out something around 1800 HP without power adders, and they will set it up for nitrous if desired.