400 motor- block casting 230

[Garys1969RR]

Just for those who may be looking for one of the 400 "Super Blocks", just saw one on the Ft Collins, Colo C List. This is the strongest 400 block the factory produced, and fairly hard to find. He is asking $1000 for it. Heading under Mopar B Body parts, Denver C List.

 

[moper]

Means mothing until it's sonic tested. It's a 50/50 shot that it's got no extra thickness anywhere due to core shift.

 

[5.7 hemi]

Holy crap! That’s pretty pricey!

 

[moparmarks]

Means mothing until it's sonic tested. It's a 50/50 shot that it's got no extra thickness anywhere due to core shift.

They have thicker webbing on the mains. Not around the cylinders.
Also there 2 different 230 blocks. The ones cast before 12-11-71 are the cold weather blocks. The ones after that date are not.

 

[moparmarks]

I gotten 600.00 just for the blocks. They are by far the strongest wedge block that Mopar made. Have a couple that I'm hanging on to.

 

[Lefty71]

I've always wondered about this oddity, if you will. Are'nt all B engine blocks beefier in the bottom webs, due to the smaller journals?? And whos really ever heard of issues with any of them, meaning the later 400's which are way easier to find. Theyre tough as nails.... And if you are truly building the killer engine, then isn't it time to go with an aftermarket block anyway?? Just my two cents, and maybe lack of experience with the bad. (knocking on wood, with my Mopar luck ;-))
It does appear from the ad that hes offering the trans with it for the $1k, but as far as the motor goes, you're likely to discard literally everything and use the block and caps only, and probably not even the caps lol.

 

[moparmarks]

Yes the 400 blocks have a beefier lower end than the 440 blocks. With the price of aftermarket blocks to find a good 400 block that soniced out good is a good way to build a 512 when on a budget.

 

[Chilsam]

Got mine..owned it since 83

 

[andyf]

I've owned a few of those blocks over the years. I have my own sonic tester so I can check to see if they are any good. Out of the several 230 blocks I've owned only one of them was worth any money. Complete pig in a poke buying one of those blocks. No way would I pay anything close to that much money for one unless it came with a sonic sheet. Ma Mopar didn't know squat about quality control back in the 70's so those blocks can easily have one or more thin cylinder walls.

 

[Garys1969RR]

I agree with what has been said. The 230 blocks have the biggest and strongest main web of any big block I've seen. 440 source goes into more detail about this on their website, and makes for some interesting reading. Of course, you need to make sure the cyl walls have adequate thickness, too. I used a 630 block for my 400 based 451 build, and it ran Great! I think this motor is worth around $300, but he is unlikely to sell it for that.

 

[fratzog lover]

Andy is correct. Web thickness is great. Core shift is not. Nothing more fun than spending 1K for a block for your stroker and cracking a cylinder on your 6th pass down the strip. But hey, if you need another overpriced mopar big block...


https://www.ebay.com/itm/440-Dodge-...nal-engine-2-12-71-casting-date-/253895781750

 

[Cranky]

I've owned a few of those blocks over the years. I have my own sonic tester so I can check to see if they are any good. Out of the several 230 blocks I've owned only one of them was worth any money. Complete pig in a poke buying one of those blocks. No way would I pay anything close to that much money for one unless it came with a sonic sheet. Ma Mopar didn't know squat about quality control back in the 70's so those blocks can easily have one or more thin cylinder walls.

How many of the Big 3 had much quality control back then plus the blocks were probably overbuilt for what their intended use was. Having core shift bad enough to be a race engine was probably just fine for a grocery getter....

 

[moparmarks]

Yep core shift was common in this era.

 

[fratzog lover]

How many of the Big 3 had much quality control back then plus the blocks were probably overbuilt for what their intended use was. Having core shift bad enough to be a race engine was probably just fine for a grocery getter....

Who thought back then that there would be 650HP 500 inch strokers driven on the street? I thought having headers, an Edelbock intake and a used 600 Holley made me a bad boy in 1979. The stuff we take for granted was a pipe dream back then!

 

[Cranky]

I thought having headers, an Edelbock intake and a used 600 Holley made me a bad boy in 1979. The stuff we take for granted was a pipe dream back then!

Having that in the late 60's wasn't even good enough lol

 

[Challenger340]

Means nothing until it's sonic tested, and by the looks of the orange repaint in the Engine posted it's already been rebuilt ? already over-bored maybe ?

 

[fratzog lover]

Means nothing until it's sonic tested, and by the looks of the orange repaint in the Engine posted it's already been rebuilt ? already over-bored maybe ?

Yes! Did the seller even think about what the correct color should be?

 

[andyf]

How many of the Big 3 had much quality control back then plus the blocks were probably overbuilt for what their intended use was. Having core shift bad enough to be a race engine was probably just fine for a grocery getter....

It is a fair question but once you spend some time in a machine shop with a sonic tester you'll know the answer. Chevy had fantastic quality control on their blocks, especially the big block engines during the 70's. I don't know why, but they did. Very few BB Chevy blocks have core shift and most of them have very thick cylinder walls. Whoever ran the casting plant for Mopar in the 70's wasn't working very hard or didn't care about quality control. Mopar blocks cast during the 70's are very inconsistent with most blocks having at least one thin cylinder.

You are correct about the fact that they are good enough for a grocery getter. The Mopar blocks don't have problems until you get up past the 650 or 700 hp range and then they start to come apart. You should be able to run them at 500 or 600 hp for a long time but if you're going to build a serious engine then you most likely need to start with a pallet load of blocks and pick the best one.

 

[Cranky]

Yeah, I've read that the rat motors were really decent but when you hang cutter into the metal and hear a real difference in sound vs a Mopar, you know the grade of cast iron was fairly soft and that was the case on their mouse motors. I would imagine with today's rings, that's not an issue but it was for the guy running chrome rings back in the day and for some reason, a lot of guys thought using chrome rings was the way to go. Didn't hang out too much with dirt track guys but I'm thinking that thought process came from them....and it wasn't too long ago that I read up on the strength of the old Chevy big blocks. And maybe softer cast iron is stronger since it might not crack as easy.....?

 

[fratzog lover]

Yeah, I've read that the rat motors were really decent but when you hang cutter into the metal and hear a real difference in sound vs a Mopar, you know the grade of cast iron was fairly soft and that was the case on their mouse motors.

Nickel. The underappreciated Stepchild of metals.