400 sb
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400 sb
so i came across a 400 thats been bored over 0.030 the guy built it to put in a camaro but now he is selling it. he wants 550 for it its a complete motor is this a good deal? and what casting numbers should i look for to make sure it is a 400 this is my first swap. just want to get it right
#2
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youre lucky to find a 400sbc at all for that price, let alone one thats bored and presumably good running/low miles
thats actually really dirt cheap if he has all that work into it, i would be weary probably, the block alone is easily worth this much, let alone the crank, rods, pistons, and so on
he must be rich and doesnt care, or he is hiding something
rather than go with casting numbers check the flexplate for a weight attached to it, and also the balancer that it is solid and has metal area removed from the back outer edge of it ill try and get a pic or two from my 400 in my 77
but, if theres no flex plate and youre not sure on the balancer(it isnt perfectly smooth all the way around and hollow inside the back) the 509 is the most common casting number of the 400 blocks- cept some earlier years ones,
if its a 509 block then it will say 509 in large numbers on the side of the block
also there will be a bulge at each cylinder on the outside of the block, noticeable
thats actually really dirt cheap if he has all that work into it, i would be weary probably, the block alone is easily worth this much, let alone the crank, rods, pistons, and so on
he must be rich and doesnt care, or he is hiding something
rather than go with casting numbers check the flexplate for a weight attached to it, and also the balancer that it is solid and has metal area removed from the back outer edge of it ill try and get a pic or two from my 400 in my 77
but, if theres no flex plate and youre not sure on the balancer(it isnt perfectly smooth all the way around and hollow inside the back) the 509 is the most common casting number of the 400 blocks- cept some earlier years ones,
if its a 509 block then it will say 509 in large numbers on the side of the block
also there will be a bulge at each cylinder on the outside of the block, noticeable
Last edited by Randy82WS7; 12-25-2007 at 05:35 PM.
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thanks for the info. can you take a pic of the buldge? this is my first camaro and this is going to be the first project of this size for me
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Car: '89 Firebird
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Man ... I paid 500$ for mine and it was a piece of junk with no carb and a 2 barrel intake manifold , had to pay another 800$ to rebuild it ...
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well im supposed to go look at it tomorrow. im going to put a wrench on the crank and turn it a few times and make sure that it doesnt catch any while turning it. if i get im going to tear it down and check all the internals i already have a felpro sbc gasket kit
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Doesn't matter whether it turns or not; that's not really what you're buying.
You're looking at a 400, not an engine whose crank turns. You need to be paying attention to stuff that matters to its usefulness as a 400. The ONE MOST IMPORTANT THING is the bore diameter; whether it's been bored, if so how much, and what condition the cyl walls are in. If that's OK, then it doesn't even matter if it has a crank, let alone whether it turns. If they're not OK, then it doesn't matter if it has a crank, let alone whether it turns, or even if it has 5 cranks and they all turn.
So break that down logically: if the cyl walls are good, then the crank turning doesn't matter; and if the cyl walls are bad, then the crank turning doesn't matter. So, under what conditions does it matter whether the crank turns?
Lesson:
Take a micrometer and a bore gauge with you, not a wrench.
None of the 400s I've ever owned or built (not that it's that many, probably not over 15 or 20 I suppose), not even the one sitting outside in my garage right now, has any "buldges". I don't know what that's all about.
I don't think I've ever had to pay ANYTHING for one. One of the best ones I've had, came in the trunk of a car I bought; the PO didn't care because it was only a small block. Most I've ever even had a friend pay was $250, and that was for a guaranteed running one, not just a core. But nowadays, in the last 15 years or so, they're getting harder to come by; so maybe they're worth more.
You're looking at a 400, not an engine whose crank turns. You need to be paying attention to stuff that matters to its usefulness as a 400. The ONE MOST IMPORTANT THING is the bore diameter; whether it's been bored, if so how much, and what condition the cyl walls are in. If that's OK, then it doesn't even matter if it has a crank, let alone whether it turns. If they're not OK, then it doesn't matter if it has a crank, let alone whether it turns, or even if it has 5 cranks and they all turn.
So break that down logically: if the cyl walls are good, then the crank turning doesn't matter; and if the cyl walls are bad, then the crank turning doesn't matter. So, under what conditions does it matter whether the crank turns?
Lesson:
Take a micrometer and a bore gauge with you, not a wrench.
None of the 400s I've ever owned or built (not that it's that many, probably not over 15 or 20 I suppose), not even the one sitting outside in my garage right now, has any "buldges". I don't know what that's all about.
I don't think I've ever had to pay ANYTHING for one. One of the best ones I've had, came in the trunk of a car I bought; the PO didn't care because it was only a small block. Most I've ever even had a friend pay was $250, and that was for a guaranteed running one, not just a core. But nowadays, in the last 15 years or so, they're getting harder to come by; so maybe they're worth more.
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i got a steal on my complete 406 for $500. only 2000 miles on the build and it spun a main after 12 years (gas in the oil). came with a dual carb intake (selling that), drag race cam (selling that), and a set of crappy double hump 1.94/1.50 (using them til i can afford AFRs. already has forged flat tops and i'm keeping the stock crank and rods (limiting revs). going performer RPM intake, demon 750, voodoo 60103, 1 3/4 LTs, and eventually some nice done-up AFRs. even if it doesn't turn over (i'm assuming you'd be rebuilding it, i would personally) that is still a good price, i've seen the bare unbored blocks go for $750 alone. good luck with it if you do get it, there really is no replacement for displacement.
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well i went and looked at it today it appeared to be in decent shape. i gave them some money to hold it till i get my tax return in a month. it wasn't seized up. yes im going to tear it down and go through it all and fix anything that needs fixing plus all new gaskets on everything cant hurt anything
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Car: 1989 FIREBIRD FORMULA WS6
Engine: TPI 305
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Are small block 400's really that hard to find??? I just found a running one for 200 bucks.Thinkins about swapping it in for my knocking 305 tpi motor.
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well its going to be the end of next month or so before i can pick it up. im going to put new gaskets, rings, and main bearings in it and anything else that might need fixing. the guy said he would refund my money if there is something terribly wrong with it. its a 511 cast which happens to be a 4 bolt main
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Car: 92 Camaro RS 25th aniversary editio
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if i use the manual fuel pump will i still need a pressure regulator? im just going to modify the intank pump to just be a pick up. i may switch over to an electric pump later but not for shure. im going to use a 750 eldebrock perfomer carb on this motor
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A mechanical pump doesn't need a regulator. I hope you're modifying the pick-up as stickied on the Carb forum.
I would never pay money for an Edelbrock carb. I might let someone pay me to take theirs, though.
I would never pay money for an Edelbrock carb. I might let someone pay me to take theirs, though.
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there really werent any motors in the late 70's that were really good anyway
I'd only let somebody pay me to take one of those carbs, if they also paid the 2-way freight so I could also get rid of it.
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Car: 89 Camaro RS
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I had purchased the 400 i had from a friend, along with the rest of the truck it came in, for $500. One of the things I was told about these was that the 2 bolt mains were actually stronger than the 4 bolts, due to the design (i hope i'm not incorrect on that info, someone correct me if i'm wrong). the other was to make sure you have a flywheel/flexplate and harmonic balancer that is correct for the 400. these are externally balanced unlike the rest of the sbc's. one of the previous owners of my motor had put on a standard sbc flywheel and messed up the crank.
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Yes that are getting harder and harder to find. If its a good black snag it up.
the 2 bolts are stronger then the 4 bolts..
Good luck on your build. They are fun motors. Ive built a few of em.
BTW if anyone else is looking I just posted up a (509) casting good virgin bore 400 in the F/S section
the 2 bolts are stronger then the 4 bolts..
Good luck on your build. They are fun motors. Ive built a few of em.
BTW if anyone else is looking I just posted up a (509) casting good virgin bore 400 in the F/S section
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hopefully the IRS isn't slacking to much and will get me my money this week like they're supposed to so i can go get the motor. i was wondering if yall think this cam would work fine for alittle performance and driveability. its part # LUN-00010LK advertised 292/292 and @0.050" 230/230 Max lift .480/.480
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It's an "old standby", run-of-the-mill, unexceptional cam.
You can do better no matter what you're trying to accomplish.
What heads?
You can do better no matter what you're trying to accomplish.
What heads?
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Car: 84 Camaro
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the two bolt mains are stronger then the 4. iv always been told to look for 73 and earlier 4 bolt 400 hundreds b/c of the 74 and up 2 bolts being ****, but hey idk thats just what iv been told. anyway i have a 72 4-bolt 400 in my 84 camaro its a bad *** swap good luck
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If you are planning 500hp or less, 2 and 4 bolt are fine. The 4s have thinner walls due to the outer cap bolt. With a 4 bolt, probably don't want to go go above 30 over unless you sonic check it - maybe a good idea with either. I've read that the blocks check very differently depending on production run, etc. I have a stock bore 4 bolt from a 73 Impala sitting in the garage that will eventually be in one of the Camaros.
-Dan
-Dan
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Car: 84 Camaro
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here is a link to some pictures of my car that the 400 swap is in... http://s86.photobucket.com/albums/k1.../The%20Camaro/
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the guy said it had vortec heads on it. is there any way to make sure that they are vortec heads and not just a newer model head? i know it has the center bolt valve covers.
LiveFastDieFun what starter did you use on your 400
LiveFastDieFun what starter did you use on your 400
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Look at the intake manifold, or if it doesn't have an intake installed, the intake mount bolt holes. There are only 8 total mount bolts, two on each corner, and they go straight down into the head rather than being perpendicular to the gasket face. Some Vortec heads are drilled to accept either type of manifold, but I don't think I've seen non-Vortec heads drilled to accept a Vortec intake.
The surest route is to pull the valve covers and get the casting #'s.
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Re: 400 sb
if i remember right the two center bolts on the intake went in at an angle because the intake bolt holes had been sloted some for the bolts to fit
any suggestions on a cam? i would like to get a cam and lifter kit
any suggestions on a cam? i would like to get a cam and lifter kit
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Center two bolts? In that case, not Vortecs. Get the casting #'s. They're probably LO5 swirlports.
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Re: 400 sb
I scored a 75 2 bolt block that is a low mileage untouched short block that has new pistons, rings, bearings and ARP hardware. The block didn't need to be decked or bored and I am getting my parts together for a summer build with my Trick Flow Twisted Wedge heads, which are already drilled for steam holes, and I am going to run a hydraulic roller cam in it. I am going with the Trick Flow #TFS-31402001 cam which is designed for their heads, Comp Cams hydraulic retro roller lifters, Beehive springs, retainers, and locks. Compression will come in at 9:95:1 with the pistons and the depth in the hole they sit. Hoping to get some good power and torque from this combo. I say, go for it and have fun..
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Re: 400 sb
so does any one have any ideas on what a good cam would be i dont want to have tohave a stall
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Re: 400 sb
matt i went to the parts store and just told them hey i have a 400 out of a 72 blazer and its in my 84 camaro and they gave me a starter. so just tell them what you have and if you go to a decent store they should know what there talkin about, and help you out. im goin to work on it today so ill look for what it is but idk if it will say it on the starter itself and i havnt got the box anymore
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Re: 400 sb
so does any one have any ideas on what a good cam would be
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Re: 400 sb
i haven't got the money yet but i am going up there this weekend to get a spindle so i will check on the heads. its my understanding that all spindles are the same on camaros as long as it aint 1le right?
#38
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Re: 400 sb
here is a link to some pictures of my car that the 400 swap is in... http://s86.photobucket.com/albums/k1.../The%20Camaro/
im putting a 400sb in my car also. i bought the engine for 75 and bought a new scat crank . i bought a rebuild kit from northern auto that came with an r.v cam. basically from your pics we have the same car. i also have a 700r4 and all the chrome.
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Re: 400 sb
Go with an aftermarket Hitatchi mini starter and it will probably have 2 sets of mounting holes such as mine so it fit a small block with a 153 or 168 tooth flexplate. If you run a 400 then you will need an externally balanced flexplate and harmonic balancer or you could do what I am going to do and go with a balance plate that bolts between the crank and the flexplate to make my 153 tooth flexplate an external balanced unit since they don't make an external balanced 153 tooth for a 2 piece rear main seal only for a 1 piece. Hope this helps..
#41
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Re: 400 sb
well the 305 were wierd and could have either pattern
on the 87 305 TBI trucks they were 168 tooth and staggered
but the 83 305 LG4 cars were 153 tooth and straight across
it was funny like this
you will just have to look and see
being a 400 or not doesnt matter,
but the pattern does
staggered, or straight across
thats it
on the 87 305 TBI trucks they were 168 tooth and staggered
but the 83 305 LG4 cars were 153 tooth and straight across
it was funny like this
you will just have to look and see
being a 400 or not doesnt matter,
but the pattern does
staggered, or straight across
thats it
#42
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Re: 400 sb
To use the 153-tooth starter, or a starter with both patterns, you MUST have the extra hole. if the block doesn't have the hole, then the hole in the starter won't line up with a hole in the block, to put a bolt into. You CANNOT use the existing hole in the block if it's not the 12.8" one, because a bolt in that hole if there was one, would go RIGHT THROUGH THE MIDDLE of the starter drive.
#43
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Re: 400 sb
i just did a cross reference on advance auto's web page and found no starter compatible with both the 305 and 400. im not saying that its not possible just not on there site.
#44
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Re: 400 sb
you guys are over-complicating things here
most all blocks had three starter bolt holes, except for most or all of the 400 sb engines
and you cant go by the listing at these stupid parts stores,
first of all you have to know exactly what year makes and models of the 305 equipped vehicles used what size plate and therefore what starter nose pattern it would have used
a 305 large diameter plate/staggered bolt nose starter will work and fit on a 400 with the same, and vice versa
same ones
all the the difference is in the plate diameters and bolt patterns
have to match them up
regardless of engine size and application
it seems that most or all the 400sb came with the large flexplate/staggered bolt starter, like my 77 one has,
and all of the carb 305 80-up seem to have small diameter plate and therefore straight across bolt pattern
oh, and FYI: there was no sb400 in the trucks until 73
http://www.chevytrucks.org/resources...evy_trucks.htm
"Chevrolet's 1970 pickups continued without appearance changes. The 396 V8 was replaced by the 400 V8 (402 ci), this was the only engine change"
the 400 in the trucks before 73 was the bored out 396(402)
GM called this engine(marketed them as) the big block 400(70-72 years only)
vs. the small block 400 in the 70-80 cars and 73-up trucks
the starter they gave you if you asked for a 72 truck 400 one would be a 402 one and most likely staggered bolt pattern and would work on the 400 small block and on any 305 with large flexplate
he is just going ot have to look at the bad starter on the 305 real quick and see what pattern the nose bolts are
really simple
alot of the 87-up 305 were staggered, unlike in earlier years
good luck
most all blocks had three starter bolt holes, except for most or all of the 400 sb engines
and you cant go by the listing at these stupid parts stores,
first of all you have to know exactly what year makes and models of the 305 equipped vehicles used what size plate and therefore what starter nose pattern it would have used
a 305 large diameter plate/staggered bolt nose starter will work and fit on a 400 with the same, and vice versa
same ones
all the the difference is in the plate diameters and bolt patterns
have to match them up
regardless of engine size and application
it seems that most or all the 400sb came with the large flexplate/staggered bolt starter, like my 77 one has,
and all of the carb 305 80-up seem to have small diameter plate and therefore straight across bolt pattern
oh, and FYI: there was no sb400 in the trucks until 73
http://www.chevytrucks.org/resources...evy_trucks.htm
"Chevrolet's 1970 pickups continued without appearance changes. The 396 V8 was replaced by the 400 V8 (402 ci), this was the only engine change"
the 400 in the trucks before 73 was the bored out 396(402)
GM called this engine(marketed them as) the big block 400(70-72 years only)
vs. the small block 400 in the 70-80 cars and 73-up trucks
the starter they gave you if you asked for a 72 truck 400 one would be a 402 one and most likely staggered bolt pattern and would work on the 400 small block and on any 305 with large flexplate
he is just going ot have to look at the bad starter on the 305 real quick and see what pattern the nose bolts are
really simple
alot of the 87-up 305 were staggered, unlike in earlier years
good luck
Last edited by Randy82WS7; 03-29-2007 at 10:31 PM.
#46
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Re: 400 sb
well i finally got the motor yesterday and got it tore down. the casting numbers on the block are 3951511 and the casting number on the heads is 14102193 are these vortec heads? everything looked to be in good shape. the only problem i found was one cylinder had some rust in it which wasn't bad. it should clean up when i get it dipped and honed.
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Re: 400 sb
193 ?? hmmm isn't that the L98 iron head casting number ? Don't have the casting number list handy right now
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Re: 400 sb
so are these heads even worth using? i dont have alot of money. its only going to cost me $140 to get the block diped, honed, and new cam bearings put in
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They aren't performance heads. Fast355 will argue otherwise, but they aren't good for high lift or high RPMs. Keep the lift and RPMs down, and you'll be fine.