[Mustangsaly]

what do you think of a 4 bolt main #511 400 SBC Block ? The 400SBC I bought is a 4 bolt #511 block, it has a worked over set of #187 camel hump heads and is 10.5 or so CR and has a healthy bump stick. it runs real good.

I just heard the 400 2 bolt mains were a stronger block. this isn't a all out strip car but a 16 yr old will be the owner operator. I didn't pay a lot and I got some nice pieces like the heads & M21 ect.


its complete and going in a father son 74 Camaro project. this is a 74 Camaro that will have this 400SBC & M21 4 speed tranny with frame connectors and a 10 bolt posi. I'm guessing the gears are 308s or 342s. kinda hard to tell as the clutch was almost completely out of the car, so it wasn't drove much with the 350 T10 in it. I put a new water pump on the 400 and just had the 4 core radiator gone through. going to run a 6 blade mechanical fan with the factory shroud. and it's an a/c car but most all the a/c stuff is gone, and there no money now for a/c so I think I will pull the a/c condenser till we have all new a/c stuff. then I will go back with a/c components big enough to run a R134a system. I have a complete serpentine belt system with a new R134a a/c compressor.





Mustangsaly

[Double_v23]

Apparently GM Removed some material from the casting to compensate for the additional weight in some of these 4 bolt 400's. The design of the 400 is just not suited to performance applications. The mains and lifter valley's have a tendancy to crack because of the reduced weight. The bores don't have coolant passeges between them which makes running lean a dicey practise.

For mild to mid HP street applications they are fine, just make sure the steam holes have been drilled in the heads to relieve some of the pressure in the block. Or just run the heck out of it and see what happens...if you decide to get serious performance it is probably best to go with an aftermarket block.

[Mustangsaly]

thanks, as I was always told the 400 2 bolt blocks were stronger. this will have a new cooling system. but this 400 is to get him through high school. weather permiting as he graduated in 2010. and it will see 1/4mi track time starting in june.

[Stroke]

Just do it. A good 400, 2 or 4 bolt is worth making into a TQ Monster. That 4 bolt block will handle what you're going to give to a kid for the street. I built a 406 for my boy when he was 17 and stuffed it in his truck. With a 10:1 FT and a 228/228 480/480 cam and a dual plane it was a bit more than a 17 year old kid needed, for sure. A 400 in that car with a 4-speed, now that's COOL. I once had a '79 Camaro that I stuffed a 400 4bolt in - out of my '72 impala. Went through the whole motor and basically kept 'mild', the CR about 9.8:1 and only put about 218* dur with a 114 and 292adv. With those 3.42's it would easily bury the 130 speedo!

[Crazy Mopar Guy]

Originally Posted by Mustangsaly

this isn't a all out strip car but a 16 yr old will be the owner operator.

OK, you gotta chuckle a little bit...?

[Mustangsaly]

Originally Posted by Crazy Mopar Guy

OK, you gotta chuckle a little bit...?

Hey I'm easy going and remember 16 all to well ! but an all out strip car, and a car owned and operated by a 16yr old is a lot a like. this 400 should be 400 + hp pretty easy. witch is prob to much. but after we get it going if its got a ton of balls, I will unhook the secondaries till the boy figures it out. by the time he figures out the secondaries aren't opening he will prob be ready for more. hes 16 in june and the car will be done by april so if he has a handle on it by june I told him he can run it at the 1/4 drag strip.

[Studebaker]

I actually like the 400 chevy blocks. They make a great high torque drag engine, The "Siamese' cylinder arrangement actually lends it to heavy abuse without to many issued. I CURRENTLY HAVE five 400'S. The next one will be for my40 Dodge ratrod drag truck. Some key issues with the 400 block is to use main cap studs, instead of bolts, Also use a stud instead of a bolt to attach the oil pump. Because of the larger main journal diameter, the rear main cap is weak and by using a bolt to tighten down the oil pump it can distort the cap making for a failure point. I had a 400 destroked to 352 by using spacer bearings and a forged large Journal 327 crank and 6.125 rods with custom 400 flat top pistons, solid lifter 270 cam. Felt like a grocery getter until it hit about 3500 RPM, then you better get ready to shift cause the tach stood on 8000-8500 through every gear. Really Quick winder. Big bore /short 3.25 stroke was a wicked combination! It felt like the powerband on a two-stroke dirt bike. I use a good radiator, drill the heads for steam holes using a head gasket as a template and always use head studs on a 400. It almost elimnates blown head gaskets. Because of the increased 1/8 bore, it really increases the breathing potential when using 1.94 and 1.5 valves the small valves keep air/fuel mixture velocity high. this design also unshrouds the valves for better breathing. These engines really respond well to a 750 mech secondary or slightly bigger carb. these make a great street rod engine or a Drag engine.

[racermiketexas]

HEY GUYS, THERES NOTHING WRONG WITHA 400SBC CASTING #511 4-BOLT MAIN BLOCK. I BUILT AN ENGINE FOR A RACE CAR, IT HAD CAST STEEL SCAT CRANK, 6" H-BEAM FORGED RODS, AND 11 TO 1 FORGED WISECO PISTONS, WORLD SPORTSMAN II HEADS, 200CC IN TAKE RUNNERS, LUNATI .665 ROLLER CAM, THENONLY THING I DID TO THE BLOCK TO MAKE IT STRONGER WAS FILL THE WATER JACKETS HALF WAY WITH HARDBLOK. THE CYLINDER WALLS, ARE A LITTLE THIN, ESPECIALLY AT 40 OR 60 OVERBORE. NEVER HAD A PROBLEM WITH OVERHEATING, CAR WAS IN AN 86 CAMARO, ALL STEEL AND GLASS, BACK-HALF CAR, 12 BOLT REAR,4:56 GARS, SPOOL, 32X14 SLICKS, WEIGHED 2925# WITH MY 200LB BODY INIT, RAN BEST 10.54/129 @ 950' CORRECTED ALTITUDE, THAT WAS WITH GREAT AIR! USUALLY RAN IN THE 10:70'S/126. RAN THE CAR THREE YEARS WITHOUT A FRESHEN UP. SOLD THE CAR TO A GUY IN JOPLIN,MO, AS AFAR AS I KNOW HES STILL RUNNIN WITH THE SAME ENGINE. IF YOU BUILD-EM RIGHT, THEYLL LAST, USE GOOD PARTS!!

[Ruthlessmr]

Originally Posted by Mustangsaly

what do you think of a 4 bolt main #511 400 SBC Block ? The 400SBC I bought is a 4 bolt #511 block, it has a worked over set of #187 camel hump heads and is 10.5 or so CR and has a healthy bump stick. it runs real good.

I just heard the 400 2 bolt mains were a stronger block. this isn't a all out strip car but a 16 yr old will be the owner operator. I didn't pay a lot and I got some nice pieces like the heads & M21 ect.


its complete and going in a father son 74 Camaro project. this is a 74 Camaro that will have this 400SBC & M21 4 speed tranny with frame connectors and a 10 bolt posi. I'm guessing the gears are 308s or 342s. kinda hard to tell as the clutch was almost completely out of the car, so it wasn't drove much with the 350 T10 in it. I put a new water pump on the 400 and just had the 4 core radiator gone through. going to run a 6 blade mechanical fan with the factory shroud. and it's an a/c car but most all the a/c stuff is gone, and there no money now for a/c so I think I will pull the a/c condenser till we have all new a/c stuff. then I will go back with a/c components big enough to run a R134a system. I have a complete serpentine belt system with a new R134a a/c compressor.





Mustangsaly

Light use then ok,for big motors though they warp and can pull out the mains