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400 SBC question.

rjfguitar said:
I thought about selling my 400 long block after I pulled it, but changed my mind. I wouldn't want to do that to someone. I'm going to do the world a favor and throw mine in the garbage.
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K5Titan83 said:
iv also spent a lot on my 400, but im still gonna try and sell it, im gonna tell em all that's wrong with it and if it sells it sells if not il scrap it or use it as a big paper weight haha. but I can understand your frustration to with all that youv had to go through with yours
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I'll take both those 400s off your guys hands. Nothing wrong with a 400. I have been messing with the sbc400 for some time with good success. Lots off things go into engine temp (cooling system, ignition timing, carb size, etc,etc) so it can be hard to diagnose on why it would run hot. None the less I honesty believe for every one person that says 400 are junk their is some like me that love the little mouse to death.

Personally I would rebuild that mouse, 400s are the sbc torque king, perfect for truck applications.
 
Now excepting donations for "FAB's wayward home for 400sbc":laugh:

Absolutely love my 400s.
Short stroke one, rev it to the sky, not a worry in the world.
Leave it log, with the right setup, they are still a great motor.

PS- just ran 70 down the hwy for an hur. then sat in zoo traffic for 1/2 hur. the 400 sat right at 210 the entire time("stock" radiator/fan).
 
K5Titan83 said:
I might be wrong but i don't think that block used a roller cam, its a 93' TBI350, I don't think they started using roller cams in them till the vortecs did they?
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They did not, but 99% of them are still roller blocks. You just need to buy the parts, and drill and tap a few holes.

Martin
 
beags86 said:
I'll take both those 400s off your guys hands. Nothing wrong with a 400. I have been messing with the sbc400 for some time with good success. Lots off things go into engine temp (cooling system, ignition timing, carb size, etc,etc) so it can be hard to diagnose on why it would run hot. None the less I honesty believe for every one person that says 400 are junk their is some like me that love the little mouse to death.

Personally I would rebuild that mouse, 400s are the sbc torque king, perfect for truck applications.
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Anybody that wants my 406 long block is welcome to have it for free. It has a spun main or rod bearing, I believe.

I did nearly everything on mine. Right away I installed a new 4 core big block radiator, different water pump, multiple thermostats, new hoses (thought the lower once was collapsing by chance), installed Flexalite dual electric fan truck setup that pulls 4600cfm of air. Perfect timing and advance, had the carb professionally tuned with a sniffer to get the ratio as good as a qjet could do, pulled the heads off to confirm the machine shop gave me the right heads that had steam holes, new head gaskets, mechanical coolant gauge installed because I wondered if the electric gauge was not accurate.

It did not flow coolant through the engine properly. It would warm up QUICK. One thing that was weird, if I ran the heater hoses through the heater core, it would not stay cool at all, running the heater hoses plumbed to one another with a nipple would help keep it managable. Thats another thing, I froze my ass off as a kid because of that stupid engine, no heater. I believe there is something that went wrong in the foundry with the bad 400's, a casting issue in either the block or the heads. Mine hasn't been the only one. There is a reason GM discontinued that engine after only a few years of producing it.
 
FAB454 said:
Now excepting donations for "FAB's wayward home for 400sbc":laugh:

Absolutely love my 400s.
Short stroke one, rev it to the sky, not a worry in the world.
Leave it log, with the right setup, they are still a great motor.

PS- just ran 70 down the hwy for an hur. then sat in zoo traffic for 1/2 hur. the 400 sat right at 210 the entire time("stock" radiator/fan).
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You are in Michigan and it's April? What thermostat do you have? That sounds warm if you are running a 180. Mine would run 210 or so, but punch the throttle, turn on the a/c, hook to a trailer, and 220-240 pretty easy.
 
70* day probably 180(maybe 195) stat, no A/C, no summer trailer pulls yet...Ill let you know if the dunes mid summer cause temp issues.:dunno: not saying they dint have a tendency to run hot(what other motor needs steam holes in the heads?) this one just seams happy.

I probably just jinxed myself:ignore::haha:
 
rjfguitar said:
Anybody that wants my 406 long block is welcome to have it for free.

I believe there is something that went wrong in the foundry with the bad 400's, a casting issue in either the block or the heads. Mine hasn't been the only one. There is a reason GM discontinued that engine after only a few years of producing it.
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If I lived anywhere remotely close to you I would be on this like flies on sh!t. A free 400!! Sign me up!

Your correct that the foundry had some issues, during early production they had some a hard time getting sand out of the block due to the freeze plug design. I believe that it may have been the difference from one foundry to another. (they didn't just use one foundry) They also then changed the design. There are other rumors out there on what went on but the sand removal issue is the most accepted reason. Some say it's debatable if their isn't sand in some of these engines to this day!

Personally I wouldn't say a 10 yr production run isn't just a few years. And being 35 years removed from that date I think it's hard to speculate on why it was discontinued. I think it had to more with emissions and GM's grand scheme to streamline production for corporate reasons.(cough*cost*cough) Around this time is when they started to phase out Buick-Olds-Pontiac power-trains and go with the "Corporate" engines. (even though the BOP line still lived though 87)

Also I don't really give GM much credit for that era anyways, these are the people that introduced to us the 5.7L (olds) diesel and turned the average US consumer away from diesel. (the effects of this are still seen today!)

I am also not saying that they don't have a tendency to run hotter, they do. My 400 in my cutlass ran around 195-200 most days, (IIRC 160 stat) but who I am to say that's not right? Just because a SBC350 runs cooler? The fact that it puts out 400 CI naturally means it will run hotter. Is that the difference? IDK. I like the strength of the design of the siamesed cylinders, but do they run hotter? IDK

No doubt the 6.0 LS based engine is a much better the the gen 1 SBC, can't argue that. Good luck with the 6.0 no doubt you will like it.

*Thread Jack Off*
 
1970 - 1
1971 - 2
1972 - 3
1973 - 4
1974 - 5
1975 - 6
1976 - 7
1977 - 8
1978 - 9
1979 - 10
1980 - 11

That actually is better for your argument, not?

Martin
 
Oh I totally get it, but alot of people see a range like 70-80 and say ten. Guess I tend to say the same. Yes, your right to the argument aspect.

But it doesn't much matter. People are VERY opinionated about the SBC400 and most people have it pre-disposed before they even know anything about them. From what they hear. They run hot, blah, blah, blah.

I don't really know why I bother.
 
I thought it was 73-80, but it doesn't really matter anyway.

400's have higher combustion chamber temps too. Mine would ping all the time with a lowly 9.2:1 compression ratio. I had to always run Chevron premium, and if I was going to pull a trailer I had to dump in a bottle of octane booster to keep it from pinging.
 
rjfguitar said:
I thought it was 73-80, but it doesn't really matter anyway.

400's have higher combustion chamber temps too. Mine would ping all the time with a lowly 9.2:1 compression ratio. I had to always run Chevron premium, and if I was going to pull a trailer I had to dump in a bottle of octane booster to keep it from pinging.
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yeah I had the same problem with mine, if I didn't run at least 91 octane I noticed a big difference in how the engine ran and could hear the pinging

and I agree 400's aren't a very liked engine. I personally don't mind them, the problems im having with mine could be problems in just about any sbc I would think.
 
I had a bad water pump on my big block once. It was a brand new one from Napa. IT WOULD NOT MOVE WATER!! No heat in the cab, but plenty in the engine. I got disgusted and bought an Edelbrock pump. Cured it completely!
Anyway, my '70 400 has been fine with an old water pump and a 3 row radiator, and now it has an Edelbrock on it for the cam stop bolt.
 
beags86 said:
I'll take both those 400s off your guys hands. Nothing wrong with a 400. I have been messing with the sbc400 for some time with good success. Lots off things go into engine temp (cooling system, ignition timing, carb size, etc,etc) so it can be hard to diagnose on why it would run hot. None the less I honesty believe for every one person that says 400 are junk their is some like me that love the little mouse to death.

Personally I would rebuild that mouse, 400s are the sbc torque king, perfect for truck applications.
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if you were closer id sell it to ya. haha. my 400 has been a good engine, iv been pretty pleased with it. the stuff that's going wrong with mine is from pervious owners not taking proper care of it and I believe the machine shop I took it to for the lower end to be built screwed some things up, im just over the thing, had a couple people basically tell me the same stuff and im just not going to mess with it anymore.
 
I just prefer one piece rear main roller blocks, so that takes 400's out of the equation for me.

Martin
 
82355 said:
I just prefer one piece rear main roller blocks, so that takes 400's out of the equation for me.

Martin
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I'll agree with that, but raise you that I prefer LS based engines now, if were only talking gas burning of course. I'll never mess with an old SBC or BBC again.
 
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