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Engine SwapEverything about swapping an engine into your Third Gen.....be it V6, V8, LTX/LSX, crate engine, etc. Pictures, questions, answers, and work logs.
Hello just joined and this is my first post.
I'm in the process of replacing my 305 TBI with a 400 sbc. I ran into a little hiccup and was wondering if anyone else has.
So I was going to swap over the TBI serpentine system with all the accessories but the 400 SBC is missing holes/studs on one head and PS site
Looks pretty normal to me as far as "brackets". ALOT like all the 400s I've had over the years in I can't even begin to tell you how many cars & trucks.
Never really had to run any different "brackets/system" in any cars I've had 400s in as opposed to any other SBCs. Which of course its not to say, that there might be a hole or 2 you have to drill & tap, in some circumstances.
What EXACTLY are you having trouble with? That "rebuilder" temp tattle-tale in the casting sand relief plug under the pass side head next to the WP flange, that has the low-temp-melting metal in it so they can tell if your cooling system was phuqued, as in, that's why you were buying some kind of a minimal "rebuilt" motor in the first place and they want to make sure they can deny the warranty on it for something overheating related? Are you REALLY sure it's a 400? Are you REALLY sure the #1 & #6 pistons are at TDC with that whole mismatch "krome" crap cover/tab and stock crank damper on there? What's the block casting number? What heads are those? (casting numbers)
Butt hay, at least it has a bolt in the oil leeeeeeek bolt hole. Whoever built it, before they just squirted all that random color paint all over it butt didn't bother to keep it off the valve covers, knew that much. Trust me, as someone who, the first time I had a motor (not a 400 at that time) that had that leeeeek and it took me like 2 years before I found it back in the 70s, that's YYYYYYUUUUUUUUUJJJJJJJE, in a good way.
It's the 511 block with the 441 stock heads.
it's a 400 for sure 40 over
And your definitely right that paint job is sloppy lol
I know I can run the v belt setup up but I want to run a serpentine. Your probably right though only option is to drill and tap.
Here are a few pics. This was during the teardown
It's extremely strange that the 2 on the front driver's side aren't drilled & tapped. Those were the original motor mount location in the 50s, and have been used for practically every PS system since they moved the mounts to the sides. That's weird. They almost look kinda like somebody filled them with something.
The one place in the pass side head didn't have a hole until the serpentine systems were introduced so you'll definitely need to drill & tap that one, if you use older heads. I think there's enough meat there but be careful, you might hit water if you get too enthusiastic.
Kind of alot of deck clearance...
Note also, the block is missing one of the critical coolant flow holes on the exhaust side between the 2 center cyls. You for sure need to drill that too, to clear the holes in the gasket; and verify that the gasket holes are also COMPLETELY clear of the 2 round holes and that triangular shape in the corresponding place on the heads.
I'm referring to the ones outlined in magenta in this pic. They need to be totally unblocked, otherwise that place in the head under the 2 exh ports that are right together, which is the hottest spot in the whole engine, won't get enough cooling. In fact you can clearly see on the deck of that head, that the gasket was blown between the 2 center cyls, where they always blow. Probably from the head being overheated and/or the bolts overtightened. I don't see the corresponding marks on the block deck (pass side) so I'm guessing that head must have been the driver's side.
In the gasket pic, red is the dowel pins; yellow is the bolts; cyan is the steam holes (which that head's are completely crudded up on the intake side, which will also cause overheating); grey is oil drainback; and all others including the magenta ones are coolant. The holes in the gasket regulate the coolant flow and direct it to where it needs to go, which is why there are so many large holes at the center cyls, and far fewer & smaller everywhere else.
Last edited by sofakingdom; 10-15-2023 at 09:45 AM.
That is a pre 67 or 68 head. Those early head did not come with acc. holes on the PS side. I think they are 72cc or 76cc chambers. You have to make a template and drill and tap like was mentioned. I did this to a set of double humps years ago.
What are the casting numbers on both heads? Looks like a very early head on the pass. side and a late model head on the left side. Would that have been a marine engine or other special build? That's a weird deal there.
VERY low compression; 76cc. Somewhat decent flow but not "great".
Both heads in that engine pic are from that same era. 186, 041, 441X, then later on 624, 882, 993, 492, 462, etc. all has that same collection of bolt holes. For that matter, so do 416, 601 and so on; up until the serpentine system was introduced, at which time they added a hole to the end of the head that's the pass side one on that motor.
Here's a set of 186 (also 69-70, but these are 64cc, and a very good head) showing that end. Sorry for the pic quality, I had ganked these off of ebay or something a long time ago, to show what the difference between bolt-hole (186) and earlier non-bolt-hole (461) castings.
The 186 of course is the bottom pair.
And here's a partial pic of (guess what) 186 heads, on a (guess what) 400 block.
I see no reason to suspect that there's anything unusual about the heads on that motor, or that they're different castings. Just typical 70s heads, consistent with 441 casting, with no particular casting identifier mark. They very easily might be different casting #s of course, just, there's nothing in the pic that shows that.
Last edited by sofakingdom; 10-16-2023 at 01:44 PM.
Yes indeed, esp the 3rd one down. Thank you, I didn't want to dissect them to the Nth degree on the spot. LOTS of the late 60s / early 70s heads didn't have the induction-hardened valves seat, and that, in combination with the BUTTER stock valves, leads to YYYYUUUUUUUUJJJJJJJJJE valve & seat erosion. GARBAGE in that particular way; repairable, but 441s? maybe not worth it. I.e. the repair will cost more than buying better heads outright, and the "repaired" heads will SSTILL be inferior, and require $1000 or more of work to become competitive with ... something else.
Looking at your deck clearance, and just "assuming" (yeah, I know, I know) the stock chamber volume for that casting, I come up with just a shade over 9.1:1 compression for what's in that pic. Not "horrible", butt, not really exciting either.
What is this motor going into? What do you intend to use it for? What are your goals for it? What's the budget, for what's left? (assuming - again - :facepalm: - that the short block is "ready to run" except maybe for the grinding & drilling we've been talking about)
Last edited by sofakingdom; 10-16-2023 at 07:52 PM.
do you gentlemen know of any shops/mechanics in Arizona
Not a clue. Used to travel out there all the time but didn't pay much attention to "shop" even then. Not that I'm a gentleman, that almost seems like an insult actually.
Do you not have a drill? This is all stuff you can do yourself. It's not rocket surgery or anything, it's just a car. There's like A BILLION of em out there, can't be too hard to figure out. Hell even I can wrap my brain around it. Some of it anyway. Sometimes even both cells at the same time. But even with only 1 willing to participate, it's largely manageable.
You might need a sanding drum or the like also. Fits right up into a drill.
For a set of decent low cost heads for that motor you might look into Summit Racing Iron heads. They have 72cc chamber heads (good with your flat top pistons) with big valves and the modern shaped chamber that would be perfect on that motor for street use. And they are new, complete, good with unleaded ethanol gas. Would need to be drilled for the 400, see Youtube for that info. That shortblock looks like it's worth a few extra dollars to be what it should be.
But that's SOOOOPER EEEEEZZZY. Again, a hand drill is all you need, with about a 3/16" bit. Use the gasket as a template; lay it on the heads, being sure to line it up exactly with the dowel pin holes (you can use 2 drill bits to simulate dowel pins, for accuracy); center-punch the steam holes (the ones between the cyls, outlined in cyan in the gasket pic above); drill the 3 along the exhaust port side straight into the deck until they go through (¼" or maybe a bit more), and the ones on the int side at about a 30° angle away from the head bolt hole (if you go straight in, you'll be drilling along the bolt hole, and you'll never hit the water jacket). You can do that to ANY SBC heads to make them into 400 heads.
That drilling is easy with factory heads but makes me a little nervous with aftermarket castings. To the OP, are the old heads that were on the 400 drilled for the steam holes?
You can see in his photo of a head that they are (or at least, that one is), but the ones on its intake side (the higher-up, therefore more important, ones) are all plugged up with tap-water scale.
I drilled my new aftermarket heads. Easy peasy. I think the angle is 45*. Goggle search there is lots on the subject. Look into the water jacket before you start so you can see where you are supposed to drill into. Use WD 40 frequently.
I had a similar problem when I tried to install a serpentine belt system on my new GM Goodwrench 350 with cast iron heads. The PS head was missing a bolt hole for the PS bracket. So I drilled the hole. When I finished the drilling, I discovered that I drilled into a coolant passage. No way that was going to seal no matter how much sealant I put on the bolt. The metal thickness there was thin. So, I removed those heads and went for Trick Flow aluminum heads with all the necessary accessory holes.
10-14-2023, 11:33 PM
Whoever built it, before they just squirted all that random color paint all over it butt didn't bother to keep it off the valve covers, knew that much. Trust me, as someone who, the first time I had a motor (not a 400 at that time) that had that leeeeek and it took me like 2 years before I found it back in the 70s, that's YYYYYYUUUUUUUUUJJJJJJJE, in a good way.
