Well I'm getting my 400 block cleaned up to go to the machine shop in a week or two and I figured I'd put my plans on here for you guys to give me suggestions on it. I've done a ton of research but this is the first motor I've completely rebuilt so I would like advise from everybody. It's going into a 66 F100 that I plan on driving a lot, maybe not my DD but atleast 5k miles a year. With this motor I want to go for really good mileage because I am 17 and gas is expensive here in Indiana. I got the motor for free with the heads, oil pan, and 2 rods/pistons off(from the same crank journal), they all came with it though. Supposedly it had been in his friend's 70s 250 and had a weird knock or something. I took it all apart and the crank was rusted some on the journal were the rods were taken off. Not sure if the knock was actually from bad bearings on those rods or not since they were taken off. The rest of the rod bearings were fine. The heads I'm not really sure about because it looks like he cleaned them with a sander on a dremel tool maybe? It looks kinda bad. I took all the valves out and they all came right out. The pistons are all in pretty good shape, no excess of carbon or anything. It's bored .40 over and had typical rebuilder pistons so I wondered if the knock was bad quench effect maybe? Anyway I have been sanding on the decks and cleaning the threads with bottom taps and it's cleaning up pretty good. I haven't checked the bore taper yet but he talked like it didn't have many miles on it. I'm hoping I don't have to bore it past .50 or I'll be somewhat concerned on reliability... The budget on this build is somewhere in the $1500 range to have it in the truck running. I plan on having it acid dipped and then the block decked however much to make it straight, probably just .10 because it looks pretty good. Same for the heads. Then I'm probably going to need to turn the crank because of that rust. Next I will order a rebuild kit from TMeyer, probably getting a Lunati High Effieciency cam, but I also thought about a Hyd Roller so not sure yet. I plan on completely reworking the heads because they are stock. I'm going to do a very conservative porting job and put new valves, springs, and hopefully roller rockers. I'm sure I'll think of more to say but that's it for now. I'll post some pictures tomorrow. Looking forward to hearing you guys' input, sorry it's a long read haha.

 

My question is on the block? .040 is alot for this block, might not clean up? also on the rod/main bearings on the back it will tell you the sizing of journal. .010 or .020 on back of bearing. once past .020 might be looking for crank. check out your bearings and tell us whats on the back of bearings! Mild cam and budget build your gonna go hyd cam and be sure to use zinc addative oil during new startup. cylinder heads Knock out all big bumps and use common sense on mild port. also port match your intake and cylinder heads, it all matters! Be sure to polish exhaust smooth, knock out bumps and port match. it all matters. the little things really make a difference in the end no matter what build!

 

Yeah I wish it wasn't bored .40 but I can't really help it now haha I need to measure the taper and if I'm really lucky it won't need bored at all ... I am planning on using the ring end gap method of measuring the taper, is that ok or do I need to spend the money on an inside mike or something similar? That is a good idea I haven't thought to look and see if the bearings are oversize already. Should I do the port work before or after I take them to the machine shop? Also is it worth polishing the rods and/or putting in ARP rod bolts with this mild of a build? What about shot peening the crank? I also plan on having it balanced since that may gain a little bit of mpg. Basically I want to see what kind of mpg is possible with a 400 and I figure I'll have plenty of power for a 3500lb truck even with a complete mileage build.

 

i would take it to a machine shop and let them mic the block. buying the proper tools is not cheap! Can buy a Inside diameter micrometer, little bit of money but a good tool to have on hand. Definelty check the backs or bearings to see what you have on crank previous machining. good luck!
confirm block is good then work on the rest of componets. yes balancing is a good idea and helps in the long haul! Nice port work really helps these engines. Nice header for your application would be in the 1 5/8" low end torque for crusing. max 1 3/4" on header port diameter for your application. I also working on a fuel mileage performance towing application. Installing fuel injection! Been a big carb guy for a long time and still. If any question drop a message. 650 cfm would be a good place to start in your application.

 

Thanks! I'm sure I will have plenty of questions haha. My plan for carbs is to swap the Holley 600 4160 from my 80 onto this motor and then get a 650-700 double pumper for my 80 since it will be more of a fun truck once I get the 66 running. I love the throttle response on my friend's 390 with a double pumper. I pretty much have to go with a vaccuum secondary carb for mileage on this motor though right? I'm good at keeping my foot out of things when I want to but I feel like the VS will still be more efficient.

 

. The 'rebuilder' .040" pistons prolly sit well down in the hole, giving lowish compression ratio and poor engine quench effect... possibly engine-damaging 'pinging' as well when accelerating... Unfortunately, I don't think TMI and/or KB offer any improved pistons with higher compression height in the .040" oversize, either... and custom pistons are pricey...

. In gentle driving vacuum secondary or double pumper carb.'s should offer about the same MPG... tuning to proper jet sizes and power valve sizes is most important... the vacuum secondaries are mainly to prevent dumping in all 4 barrels at a lower RPM than the engine can efficiently eat them... which produces a bog and wastes gas...

. With your compression ratio, will need to be very conservative with cam size to have any MPG... like 204/214 or less duration at .050" lift... or even stock cam making sure it is installed straight up rather than advanced or retarded as factory did on emissions engines after 1970...

. Summit's budget 1 5/8" headers and dual 2 1/2" - 3" exhaust plus 4 bbl. carb. should wake up even the stock engine noticeably...

. Machinist should be able to glance at your crank and rod bearings and be able to tell you if that's where your knock is coming from... or, at least, with some simple precision measurements... some knocking sounds may also come from a worn out timing chain or worn out transfer chain in 4WD box... he can also check your oil pump's clearances...

 

A couple months ago I emailed Tim(the project got put on the backburner for a while) and he said he has from .20 to 0.60, I need to ask him again and make sure though. I'm definitely NOT using typical rebuilder pistons. I am planning to have the comp ratio at around 9.5 because I am going to run 90+ fuel in this truck. Do you think that's about right? I'm planning on those summit headers and 3in duals for exhaust. Yeah I figured I'd have the machinist look at it. I think I'm just going to get a new oil pump with the kit I'll get from Tim.

 

i have a 400 and my set up is not budget friendly but definitely what i wanted. Cleaned up the block and got it deck milled and crank grinded down( definitely recommend), running lunette hydraulic flat tappet 262/268 (sounds like a beast!), 3/8 hardened push rods, comp cam roller rockers, ordered TMI rebuild kit, running 351c 4bbl closed quench heads NOTE: if you run 351c heads, you MUST use spacers for your intake due to the deck height difference. My spacers are from Price Motorsports and are matched to my heads which cost me 3 bills and some change. 625 cfm summit carb since this will be everyday driver. Sanderson headers, 3 in dual exhaust with x cross-over and glass pack mufflers. Like i said, this is definitely not budget friendly but if you have a couple bucks to spend, these parts are worth the money. Tim helped me out a lot and is always willing to help out others with any questions so he's your man if your ever stuck and don't know what to do. FYI, this is going in a 69' F100

 

Man that sounds like a beast. Doesn't sound like much of an efficiency build haha. If I wasn't a teenager with no money for gas(or the motor parts for that matter) I would do that, but it just wouldn't be practical

 

Cole - You should have told me to come here to look for your thread. Anyway, it sounds like we are going down much the same track at the same time.

On the pistons, Tim told me the other day that they have the KB2344's in 20/40/60 over, but I don't know about the pistons you are talking about. However, if you are running the stock heads you won't have quench so might not be able to get by with as much compression as I will with either the Aussie or TFS heads, which can stand 9.5 & 10.5, respectively, on 87 octane according to Tim. Anyway, make sure you clear that up with Tim.

And on the carb side you won't need a big one for the 400 if you aren't going to wind it, so the 600 may be enough. I'd been planning on running a Eddy 1406, which is a 600 CFM AFB-style, but Tim said most of his work has shown the Eddy 1806, which is a 650 CFM AVS-style carb to be the one to go with. Anyway, another something you might want to ask him about.

 

Yeah I thought about it but I didn't want to seem demanding haha. I figure with 90+ octane fuel I can run a 9.5 comp ratio with a small cam on stock heads. And it will be getting a Holley, just because that's what I'm familiar with. I'll mess with Eddies some day but not now when I have more important things to learn about than a second carburetion system.

 

Ok. But I'm subscribed and will be following your build.

 

Thanks, I'm sure I'll need plenty of help. I wanted to take it to the machine shop this week but I've been so busy I haven't got the time to finish prepping the block and heads. The girlfriend takes up a lot of the time that would be for trucks haha...

 

Sounds like the girlfriend needs some wrench time! Either she likes it or not. Might help you with a girlfriend upgrade? Once had a girlfriend who wouldn't pee in the woods, she didn't last long! She was cute but she had to go! chat later! keep us updated on the new mechanic?

 

I found a girlfriend for you. Went into the machine shop that I'm going to use for my 400 build and the guy's daughter was running the boring machine.