Hot Rods What's the advantage of a 400 SBC?

Don't really like 400's myself, they just dont scream like like a small block. Built a mean one, and stuck it in a 66 Impala 4 dr, with a 2,500 stall, would just fill intersections with smoke from the one legger in the back.

Anyhow..back to the not screaming like a small block, the rpm range of 400's is more like a big block, and since I don't like small blocks in general really, I'd just rather have a big block than screw with a 400 anymore, that being said, if I were to build one again, I would probably de-stroke it with a 350 crank, and make it into a 377...big pistons, and get the rpm back.

Oops, this thread was about what advantages...but I would think that would be fairly evident.

 

400 block with 350 crank = internally ballanced, great reving, reliable, reasonable priced large CI small block. Love mine in OT car!

Russ

 

I'm sold!! On the minimum. What do I want to do to the motor. It's going in a Street rod. I do road tours in the summer. I want it to sound nice when I arrive.I read it has great torque so leaving is not an issue. I will get it to my machine shop right after purchase. Anyone have a thumper cam in one of these? I will have a TH350 behind it. I like the idea of having a big CID in a small block.

 

My 12sec street/strip chevelle has more or less a stock bottom end and I spin mine 7k (oh and engine is 6 years old now- no problems)

 

Just put one up for sale in the classifieds if anyone is interested! Here in Kentucky all the stock car racers buy them up as soon as they find one.

 

Just be SURE to use a flexplate or flywheel DESIGNED FOR THE 400. A 454 is NOT the same. They have different balance characteristics.

 

I had saved this link a while back:
http://www.gregsengine.com/converting-350-heads-to-400.html

 

You might want look into an RV cam for it.... Builds torque in the lower rpm range right where you want it for everyday driving... Nothing bigger than a 650 cfm carb for it.. Hope that helps!!

 

I have a 406 in a 22 ft. boat, it flys.

 

That one went right into my files.... Thanks!

 

had one in my 70 monte carlo, that thing ran like a bastard, sold it, guy totaled it, bought it back and resold it, should have kept the motor, dumbass.

 

Baddest engine ever once you switched over to camel humps heads or better and used true flat tops or forged pop ups back in the day. From a dz302 crank all the way up to stroker 400 block combos..327/350/377/406/421/434

The best block is the 70 model with 2 bolt mains, they dont use the center untapped freeze plug. I just built a 377 using an old de-stroker setup. It contains an 1182 steel crank with spacer bearings, 5.7 pink rods, and shaved TRW 2311 forged dome pistons. The heads are 041x. In other words, its a 1970 lt1 with a 4.155 bore.

 

You could tap the block to use both style starters. Cant beat vortech heads and edelbrock rpm cam kit. Use dish pistons to keep compression down.

 

Could I get one to work with a 153 tooth flexplate? Would I be looking at a big machine shop bill to get it to balance?

 

You just need a starter that has all the holes and tap your block if it doesnt have the third hole -easy do this yourself at home. On stock 400 your flexplate and balancer is you balance with stock weights attached on it. In a 377 you use 350 balancer and flexplate/no weights on it.

 

I thought "all" 400 sbc's from '70-'72 had 4-bolt mains... You might want to look into that...

 

My buddy has a sbc400 with a supercharger and is putting down 550/hp at the rear wheels

 

if I remember correctly, didn't the sbc 400 have center cylinders that were really close together causing possible head gasket failure? That being said, I ran one in my 67 Nova. It ran like scalded dog!

 

Been running one in my home-brew TT for years. latest version has performer RPM intake & cylinder head combo with factory tube shorty headers. truck weighs 6400 empty, but with the stall converter & 3.54 gears she moves out fine buckets of torque, i rarely take it past 5500.

 

They all had 4.400" bore centers including the 400's.

 

Had a 400 SBC in a 78 monte Carlo that would melt the tires from a standstill even with 2:29 gears in the rear. Unbelievable gobs of torque at any speed! Wish I still had it.....

 

If you spend a little time on a 400, it'll rev just like a 350.

My alcohol race motors (dirt circle track) are 406 CID, and we run them up to 7,800 RPM at the end of every straight. That motor made damned near 750 HP while doing that.

Internally balance it, use the splayed 4 bolt caps (in a two bolt block, obviously), and light pistons, and you're good to go.

The point of using the small block is that it's nearly 200 LBS lighter than a big block, while having the same displacement.

Pretty hard to beat that kind of combination without going to an aftermarket alum block.

 

Built one in the eighties. Forged stock trw replacement pistons with dish and double hump heads with 2.02 and 1.60 exhausts. Stock rods resized with new bolts to avoid cam clearance issues. Crane solid cam with around 240 duration @.050 and .550 lift. Edelbrock victor junior intake and 700 holley double pumper. In my 63 Nova ht it ran 11.54 @117 on pump gas shifting at right around 6000 because it seemed to level off after that. Great runner!!!!

 

My advice is to put the Right cam in it for the way you useing it. Forget that Thumper show off crap, I don't even know what the specs are on a Thumper cam.

 

My buddy runs a destroked 400 sbc with old brodix heads and that thing is a animal

 

400 rods are shorter! they make great engines, use a head gasket for a templet to drill the cooling holes and use the largest valve 350 heads you can get your hands on. damper and flywheel are 400 specific, bore .030 max and have a 406, use flat top pistons. enjoy (btw, i use special pistons and 6 inch rods in 350's and 400's for race engines)

 

have a motor home 400....was supposed to be a 350...maybe i'll just keep it...

 

Plug all the steam holes in my 400's to keep the cracks from forming in the deck that usually then spread to the cylinders.In turn don't drill them in the heads either,but i run a stewart h2o pump and have a couple holes drilled in the outer perimiter of the thermostat to help bleed air,The 400 bowtie blocks had no steam holes.Ive ran many without holes in the heads and factory steamholes in the block without a problem,just have to move the water through the block with a good pump and make sure the air is bled out.

 

yeah flex late & balancer-cylinder heads too- I have never heard of the torque convertor issue though -I had a healthy 406 in my Willys wagon that took abuse for a few years then sold it off - saw it a few years later parked by itself withj different wheels/tires and the hood up-waited around about half an hour nobody showed up -I wanted to buy it back - left a note and never saw it again...never had aproblem wi9th the 406 manual valve body turbo 400...

 

Back in the day when the 400 was THE motor to run in your oval dirt track car we never drilled the head for steam holes.. in fact we always tapped and plugged them in the block.
Yes the 2 bolt main blocks with the boss, but no hole, for the middle freeze plug was the best one to start with.
Man we built a ton of those... hard to believe all the blocks havent been used/blown up by now.
With the after market blocks being so much better and stronger these days I havent seen a stocker 400 come through the shop in years