400 SBC Build

[REVINKEVIN]

Hey. I have had several 400 SBC engines. I have one right now in fact. It’s in my 1986 C10. I have done quite a bit of research on these and I have never had a problem with them. A big aluminum radiator will make sure that they run cool, even in the Houston heat. Here is what I did when I built the 406 for my truck. I started with a 4 bolt block and had it bored.030 over. It has a turned.010 crank, 5.7 rods, and 10:1 hyperutectic (sic) pistons. It has a custom ground solid flat tappet cam, ported Air Gap intake, 770 Holley Street Avenger carb, and AFR 195 Eliminator heads. The truck has great mid range torque and pulls right up to 6,000 rpm. If you build a similar engine for your truck, you won’t be disappointed.

 

[GO-N-BRK_84]

What fortuitous timing! I just pulled my 400 SBC w/TH400 last night! I will be following this thread closely, I'm shooting for 450-500 hp.

 

[Doppleganger]

Love the 400. Had a 406 in my first square. Torque-monster. Found it in a JY in a '72 Impala with 70k and a 2-barrel carb on it. Always heard the heads were infamous for cracks so had them magnafluxed. I think I bronzed the carb and set it next to my baby shoes.

Would have had one in this truck but really wanted a roller cam and the cost to convert a 400 was twice what the motor cost.

 

[REVINKEVIN]

Hey. I never saw what your budget is for your engine. Like mentioned above, a complete retro-roller cam kit is expensive at around $1,300 and AFR heads are about $1,800. So there’s $3,100 right there without even touching the engine. You can do a stock rebuild with the cam that you first mentioned, Performer intake and 600-700 carb, and some headers and have around 375 hp with over 400 lb/ft of torque pretty easy. That’s a good power plant for your truck.

 

[Dooley]

Last 400 I did has been some while.
#3951511 casting.
I ran stock 3 angle valve grind heads with 9.5 flatop pistons. Bored 30 over.
Wolverine RV cam.
intake and exhaust are .4425
intake and exhaust duration is 288@50
Overlap 64
Lobe centers 107
intake opens BTDC 0
intake closes at ABDC 34
exhaust opens BBDC 44
exhaust closes ATDC 10
Rocker Arm ratio 1.5 :1
Stock intake with a Quadrjet with electric choke.
Pushed an 8.5' Western plow for over 20 years with no problem in a 1980 K10.