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440 build- questions from a novice

DreadPirateRob

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12:23 PM
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Oct 16, 2019
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Location
San Diego, California
Hey guys,

I was driving my 73 Charger (400 Mag, smog engine) last week (around 70 on the freeway) and the engine started revving strange. Tach jumped to about 3700 which is really high for 70, and then it calmed down for maybe a quarter mile. Then the engine started shaking and losing power. I pulled over in time, and had it towed to a mechanic nearby who really didn't give me much info other than "Valve Float - seized engine, metal in oil pan". He quoted me a rebuild cost of $2200 - $3k, which seemed a little high, based on other experiences I've had.

There's a local shop near my home that I've been frequenting, they're closing down for good and I've been buying parts left and right. I realized that I could likely build a bigger, better engine from parts, for less money than the rebuild would cost me.

I picked up pretty much everything I needed and I think my total is around $1300 so far.

The builder i know at the shop referred me to a machinist who he knows, who initially gave me a quote of $275 for testing the block, magnaflux, resurface and bore to .030. That seemed good to me, but I wanted to get another opinion first.

One of my longtime friends is a machinist, and owns a shop. He's very capable and always does steller work. He and I have done lot of projects together and he's honestly a great guy.

I asked him if he'd be willing to work on my parts, even though I know he doesn't like mixing friends and work together. He said yes, and that he'd give me a great deal on the pricing. I told him that I know this is his livelihood, and if he does give me a discount I wouldn't expect anything crazy, his time is valuable and he shouldn't prioritize my job over a full paying customers work just because we're friends.

I went over today, dropping off parts and he quoted me a price which I think sounds fair considering everything that he's doing, but I don't have a good enough baseline to know if its in the right ballpark.

Heres what he's doing for me.

Valve Job, bore and hone (.030 over), very light resurfacing of the block, magnaflux everything, press pistons, doing an r&r on the pistons and rods, installing the cam bearings, main bearings, and baking the engine. Hes also resurfacing, testing and fluxing a set of 915 heads for me, I believe hes including this cost in his price for me.

Without me giving a number, what would a reasonable price be for the work being done?

I want to make sure hes not severely under undercharging. Ive heard a few different answers and you guys are the best people to ask. Thanks!
 
Is your 400 block still good? If so. I might recommend a 400 stroker build. With a 440 crank. You will get better performance than a 440. And will be a better fit with your existing engine bay modules. (Exhaust, intake, even pulleys and mounting brackets. Ect...) JMO of course.
 
I just had a 440 done with pretty much everything you listed. Block prep, bore 30 over, cam bearings, soft plugs, surface. Valve job with new exhaust valves, surface. Turn crank, recondition rods, press pistons, balance. Was just over $1300 in machine work.
 
I just had a 440 done with pretty much everything you listed. Block prep, bore 30 over, cam bearings, soft plugs, surface. Valve job with new exhaust valves, surface. Turn crank, recondition rods, press pistons, balance. Was just over $1300 in machine work.
I assume that was the machine work only? I'm not 100% sure if the OP will be building the engine or his friend will be - maybe I missed something or I am assuming something I shouldn't. :rolleyes:

To the OP: The really critical part of any engine build is to measure everything and ensure all tolerances are what they should be. For example, if the mains are out of spec, then the caps need to be cut and the engine align bored. The crush force on the bearings is critical for proper operation and longevity. This wasn't listed so I am assuming someone has checked this and everything is good. Don't take chances; make sure all appropriate tolerances are carefully checked so you end up with a good engine build.

Finally, I second reusing the 400 block. If that is the original engine to the car you should at least keep it. It may not matter now, but one day it might.

Good luck with your build!

Hawk
 
I assume that was the machine work only? I'm not 100% sure if the OP will be building the engine or his friend will be - maybe I missed something or I am assuming something I shouldn't.

Yes machine work only.
 
You’re asking for an opinion for a comparison on price without telling what he wants/the price is, no one can do that.

In my experience you can’t rebuild a motor with heads etc for $1300 in parts and $275 in machining labour.

I’m doing a 451 right now which will run me about 6 times that amount ($6-10k depending on a few variables would be common in my opinion, ie, valve train, aluminum heads or not, etc)

I think you get what you pay for, even the first guy at $2200-3,000 sound really low to me.
 
Hi Rob, sorry to hear you had motor probs!
Done loads of machining on 400 and 440 motors and it always comes out around a $1000 for basic rebuild work.
It can be double that if you have a seriously worn out motor, with issues...
Any sort of crank failure is a bad start.
A good machinist will look inside and give approximate quotes for all the work he or she can see?
A 400 is a good motor but I would put the money into a 440 with a stroker kit, bigger to start with.
This was a 542 I did a while back...
All 440 Source parts, heads everthing, can't go wrong (well you could if you go cheap on machining)lol

Nick's 543 motor.JPG
 
Just finished a 512ci 440 for a mate and he gets better gas miles with it than the worn-out 383 it replaced!

Go figure...:wtf::screwy:
 
Dont know what you budget is but if its affordable to you, I would look at investing in a set of aftermarket heads if you dont want to do a stroke.
I think you would probably come out money ahead, pretty substantial power gain over stock 915s and take 40lbs of the nose.
 
One of my favourite heads the 915!
Hard to find now, a good set...
Yep, the iron head era is OVER!!!
'Cheap as Chips' aluminum is the only way to go...:mob:
 
Hey guys, thanks for replying!

My friend is charging me $800. He showed me his work book where he writes the job and prices, and showed me that he generally would charge $1100 to a walk in customer.
V5GMVG.jpg

I called the other shop and the $275 fee is good, but their quote to do everything my friend is doing is $1400, so I'll definitely use my friend. I'm going to buy him something nice for Christmas as well to thank him for the work and the discount.

This is a list of what I've spent so far on the 440. I didnt mention in the last post, but I had a credit for trading them a dual snorkel air filter housing I wasn't going to use, which they can sell basically instantly.
V5GeRp.jpg


With the costs thus far, ill be at 2388. I was offered $500 for my 400 block which I have, but I haven't decided anything yet. The first mechanic I towed it to didn't give me a summary on how bad the block was, other than metal being found and a lot of work being required. When my parts shop told me they could get me the parts for a 440 cheaper than the rebuild I decided that was likely my best course of action. I'm not looking for anything crazy power wise, but it won't take much to improve on that stock 400. I have a comp camshaft (21-224-4) that I was going to put in 400 that ill move to the 440 block. I need to find some piston rings for 030 over, a timing chain and I think an oil pump.

I'm not opposed to taking things slow and assembling the engine myself once the machining is complete.
 
You’re asking for an opinion for a comparison on price without telling what he wants/the price is, no one can do that.

In my experience you can’t rebuild a motor with heads etc for $1300 in parts and $275 in machining labour.

I’m doing a 451 right now which will run me about 6 times that amount ($6-10k depending on a few variables would be common in my opinion, ie, valve train, aluminum heads or not, etc)

I think you get what you pay for, even the first guy at $2200-3,000 sound really low to me.


Sorry, I didnt include the heads in my pricing since I was having them done before my engine seized, so in my head its a different project, lol. My friend was charging me 200 to machine those, I don't know if he's including that in the 800 or if its separate.

I think I'm going to hang onto my 400 block after I take it out. I'll hang onto it and over the next year or two I'll slowly buy the parts to build it into a stroker
 
You’re asking for an opinion for a comparison on price without telling what he wants/the price is, no one can do that.

In my experience you can’t rebuild a motor with heads etc for $1300 in parts and $275 in machining labour.

I’m doing a 451 right now which will run me about 6 times that amount ($6-10k depending on a few variables would be common in my opinion, ie, valve train, aluminum heads or not, etc)

I think you get what you pay for, even the first guy at $2200-3,000 sound really low to me.
My 451 build was in the $6k range. (But had 440 crank already cut down and balanced for 451 build) 1/3 cost is heads. (Easily) Like the man said. You typically get what you pay for. In closing? Keep in mind your car was setup to house a B-block. Why not give her a 451 build?
 
My 451 build was in the $6k range. (But had 440 crank already cut down and balanced for 451 build) 1/3 cost is heads. (Easily) Like the man said. You typically get what you pay for. In closing? Keep in mind your car was setup to house a B-block. Why not give her a 451 build?

I get it, and plan on building the 400 into a stroker in the next few years, but based on the deals I was able to get on parts and machining, this will be less expensive. Ive got a 4 kids, (7 month old and 2 1/2 year old + 2 teens) so its hard to justify spending more than a few grand on a build right now.
 
I see the parts list says sealed power pistons. That would be the most important thing to take care of from the get go. You will end up with a 7.5:1 compression turd if you don’t get the pistons right.
 
I see the parts list says sealed power pistons. That would be the most important thing to take care of from the get go. You will end up with a 7.5:1 compression turd if you don’t get the pistons right.

ALL sealed power CAST pistons are 7.5 to 8:1.... NO SUCH THING as a CAST Piston any higher CR from any Manu

This is where the first mistake gets made every single time rebuilding a 440 Mopar.... because now the dork machinist will insist he has "used them all the time".... yada... yada... RUN Forrest RUN
 
@DreadPirateRob please read post 15 and 16. If it’s not too late for you to return the ones you bought you may want to consider doing so. Also, if you you haven’t really begun any of the work/machining you listed in your ‘spent so far list’ you should maybe pump the brakes a little and re group. The cost of doing the 451 isn’t much more than doing a stock 440 like you are planning. Just a little extra machining on the crank to bring the main journals down to fit the 400 block and perhaps a little ‘clearancing’ here and there. Plus you won’t be spending on a core block as you already have the 400.

If you want to stick with the 440 I’m not 100% sure but if memory serves the Keith black hyper U pistons KB236 or KB237 is maybe something you should consider instead of the 7.5:1 cast versions you claim to already have purchased.

I’m sure @Challenger340 and others could shed some light on that and put together a parts list for it or at the very least steer you in the right direction.

Good luck!
 
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@DreadPirateRob please read post 15 and 16. If it’s not too late for you to return the ones you bought you may want to consider doing so. Also, if you you haven’t really begun any of the work/machining you listed in your ‘spent so far list’ you should maybe pump the brakes a little and re group. The cost of doing the 451 isn’t much more than doing a stock 440 like you are planning. Just a little extra machining on the crank to bring the main journals down to fit the 400 block and perhaps a little ‘clearancing’ here and there. Plus you won’t be spending on a core block as you already have the 400.

If you want to stick with the 440 I’m not 100% sure but if memory serves the Keith black hyper U pistons KB236 or KB237 is maybe something you should consider instead of the 7.5:1 cast versions you claim to already have purchased.

I’m sure @Challenger340 and others could shed some light on that and put together a parts list for it or at the very least steer you in the right direction.

Good luck!

Thanks for the reply, but I don't know where anyone got the idea that I bought cast pistons. Sealed Power was just how I wrote it on the notes, I think these are "Speed Pro" Sealed power. Here is the product page for what I have.
Forged Aluminum Pistons with my 915 heads should rate me around 10.17 compression.

https://www.jegs.com/i/Sealed-Power/844/L2355F30/10002/-1

I understand that the 451 isn't too much more, but as I said earlier I've got a bunch of kids and I'm trying to stick to the budget I've got in my head. With the shop I've been frequenting going out of business, I'm able to save quite a bit of money on this build. I do plan on keeping the 400 Block on my engine stand and turning it into a Stroker for future cars / setups.

My 400 engine is still completely assembled in the car, and it hasn't yet been disassembled to assess the damage or repairability of any parts, so I'm building up this 440 motor without the assumption that I'll be able to use any of the 400 Engine parts.
 
As long as you zero deck the block with those pistons you will be up there on compression. Next, with iron heads you might have detonation problems with that much compression. Cam selection may or may not make it better or worse.
 
As long as you zero deck the block with those pistons you will be up there on compression. Next, with iron heads you might have detonation problems with that much compression. Cam selection may or may not make it better or worse.

I've got a thick gasket to toss on there if the compression is too much.
How could I check on compression based on my cam selection? I've got a comp XE284H to put in. I bought it just before my 400 engine died with plans to use that to increase the bottom end
 
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