Anybody know where I can find one of these? Up here in the hills all the dirt track guys buy them up. So i cant seem to find one.

Im looking for a stock longblock to rebuild for college next semster.

It has to be complete to the heads, i don't need the accessories or the intake/carb.

I live in western maryland. The closer the better as I'll have to borrow a truck or pay for gas which in turn will really cut into my budget.

Thanks

Blyth

What's your goal?

Just wondering because you can wring HP from 350s and they're a dime a dozen.

Just something ive wanted to build since I found the car...extra cubes, no extra weight.

If it comes down to it i will build a 383, because like you said I can find a 350 any day of the week.

400s weigh more than 350s - when I replaced my 355 with a 406 my 79 Z's front end dropped down to the top of the front tires. I had good clearance with the 355 before swapping engines. I think the extra weight comes from the crankshaft and maybe the block itself. If you use aluminum cylinder heads that will reduce the 400's overall weight. Just bear in mind that your front/rear balance will be upset by using the 400 or 383.

Thanks that is something I was curious about. I do plan on aluminum heads..but that depends on how much and how far I have to go to get the block.

Just a heads up.....400's were used mostly in trucks. Trucks in the 70's and early 80's were second class vehicles and were a brunt of many abuses. Have the seller magnaflux the block with the understanding that you will pay for the check if the block checks out OK. I have had several 400 builds of various kinds and 3 out of the ten were cracked.

A general prep that I have found useful is vat clean and mag. Then I put an old set of freeze plugs in the side water jackets. I fill the water jackets with muratic acid found at pool supply stores and home improvement stores. This removes rust and preps the block for the next stage. I drain the acid, flush and run a solution of water and baking soda to nuetralize the acid. My next stage is to do a "street fill" with Hard Blok water jacket filler. This stiffens the block and will not cause overheating if you purchase the street fill which is premeasured. Then I purchase the Moroso deck stiffeners. They are a threaded plug with a hole in the center for water cooling. I open those holes in the center a bit. Then it's off to the machine shop for decking, boring and what have you. Use head studs as the steam holes on a 400 are very close to the inner bolt holes and they have a tendancy to crack there if head bolts are used instead of studs.

Thanks bilster. I was planning on head studs and maybe a short "street" fill. I'll look into and definately consider youre recommendations.

If they do weigh more (and I'm very skeptical) then it won't be by much at all. I've swapped in a few 400s and never have noticed anything. The crank is within a few pounds and if the block has more material somewhere, just remember the eight big holes are even bigger. I have a complete 406 sbc short block and a complete 355 long block that I'll be taking the intake/heads off of this week...I'll weigh both of them as short blocks and post back as it has me wondering now.

Anyone have hard numbers on 400 block weight vs 350 block weight and then crank weights?

curious...


Costas
cars and such...

Yeah, I don't have hard numbers, just know what happened to me when I switched engines. Nothing else changed - same headers, water pump, and intake were swapped over to the 406 from the 355. Would be curious to see weight comparisons too.