Is this just a matter of the scarcity of the 400 blocks vs 350's and the availability of stroker cranks, or are there other more important performance reasons I'm not getting? :confused: Or have I missed the fact and there are just as many 406's? graemlins/clonk.gif Given the chance between a 400 and a 383 for a performance street engine wouldn't going for the cubes be better, all things being somewhat equal. :confused:

Thanks Bill

Yes a similar 406 will always outperform a similar 383. Now in my case I have perfect 350 block, but the crank needs to be turned. So I can get the crank turned for $120 or buy a brand new 383 crank for $230. I need new pistons (~$100 more) as well, so the decision is pretty easy to build the 383 for $210 more.

Steve

Basically, there was a heck of a lot more 350 blocks produced (and still are) than there was 400s.
Given the choice, I'd build a 400.

1)Scarcity of 400 blocks.
2)A lot of people already have a 350 block.
3)Maybe price of pistons?
4)It takes better heads (sometimes more expensive) to feed the extra cubes.
5)The circle track guys hog the 400 cores.

That's about all I can think of.

Thanks a bunch, that was what I was thinking but usually I think wrong on these things and miss the big point. ;)

Thanks again Bill

The reason i went with a 383 is because I couldn't find a 2 bolt 400 block,(couldn't wait, because I have no patience) or I would have did the 406 thing. I found a 400 4 bolt block, but my engine builder was against the idea of using it...I don't regret going with a 383. For mainly street driving, to me, my 383 would just as much fun if i had a 406.

Originally posted by Slowpoke70:
5)The circle track guys hog the 400 cores.

when i bought my 400 sbc a few years ago in NW PA, (while living in NE OH), i kept hearing that the circle track guys had sucked up all the 400's. i seriously considered building a 383 since i had the 400 crank and a 350 block but when i surveyed the engine builders about which was best for street use they almost unanimously said i would like the 406 better. so i eventually found a block in the erie, pa area and went with that. cant say i'm sorry i did but then i dont have the 383 to compare it to. as a person who owned several muscle cars of the late 60's early 70's i can honestly say this 406 (as built now) would be competitive to almost all of them.

I would say its maybe becuz theres so many 350 4 bolt main blocks out there.Seems to be harder to find the good solid 400s.At least thats why i went with a 383 instead of a 400 on my last engine build.I wanted to build a 400, but just coudnt find the right block.Plus all the horror stories i heard about guys i knew at the dragstrip that had problems with there 400 blocks, and they were all telling me to go with a 383, so i did.Im not dissapointed at all with my 383,as its been a great street engine thats sent my chevelle in the 12.20s! Which is all i wanted.

I've heard machine shops like to lie to people saying "Oh, we founds cracks in your 400 block" just so they can build a killer engine for nothing to sell for a high price to someone else.

But then again I believe Dart makes aftermarket 400 sbc blocks.

I picked up a 400 block for free a couple years ago. It came with a broken cam, and 2 broken con rods and a dented crank. Other than a small chip out of the bottom edge of #8 cylinder, the block is fine. I offered it up cheap at a swap meet once since then, nobody bit. No problem, it's tucked away for a future build now.

its mainly because 350's are a dime a dozen, and 400's are really hard to find. personally, i prefer a 400 over a 350, because everybody and their mom doesnt have one, and they have the BB tq, in a SB package.

right now i will probably be building a 350/383 just because it would be cheaper to build than the 406 my buddy has in the garage. 383 needs a set of rods, and a top end. the 350 needs everything, including a bore, and the 406 is all fresh, just needs bottom and top end.

so for right now, on a highschool budget, the 383 will probably be the engine for me, even though i dont like the idea.

aaron

Bill - And then there are some of us who just what to be able to say "I can beat your 406 with my little 383". smile.gif smile.gif

Calling: CHRIS_USMALE

Noticed your earlier 406 vs. 383 comment. I also have a 383, soon going into my 70' Elky. (approx. 450+ hp.) Curious to know your engine and vehicle specifics. Basically, what's your set-up .. to run those 12.20's, with that "street" motor? Thanks, Brian

The 400 has a rep for cooling problems and cracking. IMO many don't want to take the chance of building one up only to have problems. Combine that with them being harder to find and you can see why the 383s are so popular. If the aftermarket blocks were $600-700 instead of $1700+ the trend would probably reverse.

I have 2 400 blocks and I'm building a 383 for my malibu. 400's have a bad reputation for cracking and heat problems (they have pretty thin cylinder walls) A local guy that builds TONS of small block chevs for different racing applications told me go with a 383 instead of a 406 and siad I wouldn't really notice the difference in power too much and the 406 would always have you wondering when its going to let go. He has sonic checks every 400 block engine he has built and only about 1/2 of them have thick enough bores to go .030 over safely.

I know around here, the 400 blocks are commanding higher prices for bare blocks, when they are available, so price and availability I believe often determine whether a 406 or 383 gets built.

Originally posted by brimac:
Calling: CHRIS_USMALE

Noticed your earlier 406 vs. 383 comment. I also have a 383, soon going into my 70' Elky. (approx. 450+ hp.) Curious to know your engine and vehicle specifics. Basically, what's your set-up .. to run those 12.20's, with that "street" motor? Thanks, Brian I'd also like to know......

Originally posted by CHRIS_USMALE:
Plus all the horror stories i heard about guys i knew at the dragstrip that had problems with there 400 blocks, and they were all telling me to go with a 383, Chris, I never knew this was a big thing. :confused: If they are that bad, then I would wonder why the circle track guys have the market on them. There is no one that beats on a motor more than those guys. :eek: Is this a big enough reason to stay away from them? So as not to post a double tread I have asked this question in the Engine Forum.

Bill

Originally posted by Junkyard Dawg:
I've heard machine shops like to lie to people saying "Oh, we founds cracks in your 400 block" just so they can build a killer engine for nothing to sell for a high price to someone else.

But then again I believe Dart makes aftermarket 400 sbc blocks. It might also be that they make more money doing 383's over 400's. If you think about it, in a 383 you have to clearance the block to clear the crank (most of the time), as well as grinding on the rod bolts to clear the camshaft (once again, most of the time), plus all the balancing and assembly you would do on a 400. In a 400 or 406, all they do is clean up the block, bore it, balance it, and assemble it. They lose hours of labor for the work that they would normally do on a 383.

But then again I could be wrong.

If that were the case that could further back the theory why they recommend a 383 over a 406.

I raced circle track a few years ago and there were alot of 406/377s but I also heard a lot of guys say they have a heating problem and arent as reliable. A majority ran 400 blocks and I think most were satisfied. I ran a 383, but by seeing what I did, I dont think 400s caused too many problems, maybe just another common myth.

So whats a 2 bolt 400, running in a car go for? motor came out of a 74 caprice. Jim

If a Pontiac 400 small block is the same as a Chevy 400, then I can attest to at least one on my cousin's 65 Tempest. The darn thing ALWAYS ran hot, from a mild build up to the current "hotter" configuration.

Finally, an aluminum radiator and an electric water pump have cured the problem (very expensive).

Ricardo

Pontian engines and Chevy engines share almost nothing in common as far as I know.

Slowpoke is correct. Pontiacs 400 is a big block as well.

Actually, I don't think Pontiac has small and big blocks do they? I thought they were all pretty much the same external dimensions, same family (except for the 301)? So there was Big Cube Ponchos and Small Cube Ponchos.

I remember reading you could put 455 heads onto a Pontiac 400 or 350 and that the swap from Small to Big Pontiac was not much of a hassle compared to SBC/BBC

Slowpoke70----They don't Pontiac has only one size block, we are talking the older blocks, my buddy has a 400 and a 350, and if he wanted he could bore out the 350 to a 455, they just used one block, and inch to inch the pontiac ones put out a ton of more foot #'s or tourqe, but reved not as high. so ya the heads are inter changeable.

I just thought of something else.

I was thinking about building a 400-based engine for my malibu but here's a few things I ran into:

1) 400s and 454 blocks around here command about the same price for a bare block. So if I was going to be spending that much for a bare block I might go with the BB even though it will be more expensive in the end because of the rest of the swap. 454 blocks are also easier to come by around here. But the fact is that I don't want a BBC, it doesn't fit into my plans for the car.

2) 400 blocks never came factory stock with roller cams. On the other hand, 350's that are roller-cam ready (hyd roller at least) are all over the place. They were produced from 87 to 92 as the ONLY 350 blocks. Some have flat tappet cams but they still have the provisions for the hold-down and bores made for the stock roller lifters. And production didn't stop at 92, that's just when the LT1 came in and some 350 cars used the LT1 but the Gen I roller 350 didn't die until a year or two ago (granted the mech fuel pump provision was deleted).

So there's another reason to go with a 383, I can build it with a hyd roller and just re-used the stock rollers instead of buying expensive aftermarket retrofit rollers. No more break-in to worry about.

My plan is to find a 87-93 5.7L Camaro and drive it til it starts to smoke or doesn't pass SMOG. Then I'll yank the motor and 700r4, part out the car as much as I can and send it off to the junkyard. Then I'll have the roller block to make a stroker with, complete serpentine belt drive and a 700r4 core along with other goodies.

Just a few more incentives to go 383.