400 sbc combos

[bigblockwilly]

Hay everybody,

I have a 400 block that I was looking to build up. Shooting for around 450 hp and 500 tq. I currently have the block a stock crank .030 over forged flat top speed pro pistons and a comp XE274H cam. Anything and everything is open to suggestion.

Thanks in advance
Willybang

 

[Don Jacks]

Biblockwilly what you'll need for this engine to hit your goals is a set of heads in the 200-215cc intake runner size,and a Performer rpm intake .Your cam will support what you want.With your quench in the .040 range,you'll be right at 11-1 with a 64cc combustion chamber.This will be too high if you use iron heads,ok with alloy heads and this cam.I'd suggest a head with 72cc's if you are using iron heads to lower your compression,especially if it's going in a heavy car.A 1-5/8th's tube size header tube will be ok here,but a 1-3/4 tube size wouldnt hurt.You will need to make sure that your pistons are made for a 5.7 in rod,and get an aftermarket bros set with "stroker clearencing"built in for rod-cam clearence.All of these parts are commonly available,and you wont need to exceed 6000 rpm to get where you need to be.

 

[7d9_z28]

LISTEN TO DON!

hes got the low down on all the best ways to do this stuff!

 

[Bugsy]

Don remember sometimes you need a small base circle camshaft too for rod clearance. this is the same combination that we ran except we had 64cc heads when you had the black nova and Bruce was running the camaro. it was good for mid 10s.

 

[Don Jacks]

Thanks,but no I dont know it all by ANY means,but I've been running a 408 in small block for about 10 years now,so I can speak a little here.

 

[jr.W]

Just some info to think about.
Last year I helped a guy at work build a 383.
Here is the combo.

6" rod, flat top piston short block. .040 deck cl.
AFR 195 eliminator heads
Single pattern isky hyd. roller cam(230 deg. @ .050, .525 lift .560 with the 1.6 rockers) ground on a 106 lca.
Compression was about 10.3
RPM air gap intake
750 pro systems carb.
MSD ignition.
On the dyno it did 522HP and over 510ft/lb torque
on pump gas. Hp peak was at 5900 rpm I think.

I think with a 400 short block and the cam ground on a 104 lca
it would make close to 550 hp.

This scat rod http://www.summitracing.com/parts/SCA-25700716/?rtype=10
is the ones you want. They are know for having more clearance than most.

 

[bigblockwilly]

Thanks for the replies guys, I was looking to run an iron head to try and keep costs down I was thinking along the lines of Darts iron eagle 210 seems to me people have noting but good to say about them and they seem like a good head for the money. So shot for about 10 to 1 with iron heads and keep it pumpgas friendly. With the compression hight of the piston im limited to a 5.7 rod, so my question now is what if I offset ground the crank and used small journal rods to get more cubes, because we all know there is no replacement for displacement. Once again thanks for the replies.
Willy

 

[425/409ER]

Thanks for the replies guys, I was looking to run an iron head to try and keep costs down I was thinking along the lines of Darts iron eagle 210 seems to me people have noting but good to say about them and they seem like a good head for the money. So shot for about 10 to 1 with iron heads and keep it pumpgas friendly. With the compression hight of the piston im limited to a 5.7 rod, so my question now is what if I offset ground the crank and used small journal rods to get more cubes, because we all know there is no replacement for displacement. Once again thanks for the replies.
Willy

Redo a set of production vortecs and you will be making 500 lbs. of tq. No need for fancy aftermarket heads to do that on a 406. Super chevy did that and got a ton of tq. with vortec heads. Cheap and plentyful.

 

[Don Jacks]

The Vortec head is what I use on my 408.You wont make 450 hp from the production head,they wont support it,but 425-430 is do-able.You'll easily make 500-525 ft.lbs.using the cam you have.You'll need to change pistons,as you'll be making about 11.5-1 on these flat tops you have.Your choice of the Darts with a 72 cc chamber will get you about 10.5on your pistons.The Dart iron eagle Platinum series with your cam should put you in the 460-475 hp range,and 525-535 ft.lbs.Remember,horsepower is largly a state of mind,it's torque that moves the car.This is largly why strokers are so much fun.If you could spend the money,the AFR heads mentioned by wjr.should put you in the 500 hp range,with no loss in torque,altho it will peak about 1000 rpm higher,they'll set you back about 1500 a set.When it comes to bang for the buck,the Vortec cannot be beaten.

 

[dq409]

The SBC is one of the best engine ever built!!!
Their are sooooo many combo you can build them into and just as many parts that can be swapped from one size to the other and one year to another that make them unlimited to what you can build!
Any combo from a 400 block with a 283 crank that spins like a banshee screaming down the highway at unbelievable RPMs to a 350 block with a 400 crank that will pull down trees with all the torq they can produce.

These little monsters can be a blast to build and run AND for a very modest price!

 

[bubbletop1961]

These all sound like good combos. I've been running 400's for about 10-12 years. The. One in the 61 now has a stock crank, stock 5.7 rods, and KB hyper pistons. Basically stock. The comp. Is only 9.0:1. It has a comp sollid roller blower cam. 575 lift. Iron eagle 215 heads. Victor Jr. Intake. 750 Carb.
Its not the best configuration I've had it in, but it still moves the 3800# impala to low-mid 12's. And driver all day on pump gas. Hope that helps some. It's been a great engine. I'd build another in a heart beat.

 

[dq409]

Why the blower cam???:?

 

[bigblockwilly]

Thanks Bubbletop I think I'm going to build a set up similar to yours only with an offset ground crank and higher 9's compression wise.

 

[bubbletop1961]

Why the blower cam???:?

I was experimenting with a Turbo at the time. Engine was out so I swapped to that cam and took the compression out of it. Before that it had 11.0:1 comp and a 617 lift sollid roller. It sure did run good then. It liked to be shifted at 6500-6700. This engine was put thru hell. It has been the best engine ever. Just for thought. I've had the best luck with timing at 32- 34deg.
What does everybody else run for timing in there 400's?

 

[Don Jacks]

Mine likes 34 degrees.

 

[dq409]

If I remember right doesn't the 400 have steam holes in the heads unlike other SBC heads?

 

[58 Apache]

Don you are right steam holes.

 

[Don Jacks]

On a street engine ,the heads will need to be drilled for steamkoles[simple and cheap],on a strip only engine,you dont need to.

 

[floyd]

My next project is turning a sbc 400 into a vortec motor for my 99 suburban.Let me know how your motor turns out

 

[Don Jacks]

Are you sticking with the factory fi system or switching to a carb,Floyd?