1973 360 Rebuild

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Cerwin

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Basically, What all goes into rebuilding a motor..

in point form..
im curious as to what im going to be paying someone for.

thanks
Cerwin
 
To do it right;

* clean and magnaflux the block to check for cracks and sonic check the cylinders for adequate wall thickness.
* measure the block to determine what machining is necessary. Bore, deck, line hone the mains, etc.
* machine as necessary and install new cam bearings
* clean and magnaflux the crank to check for cracks
* measure the the bearing surfaces and machine as necessary.
* clean and check rods for cracks
* resize and install new high strength bolts
* measure and weigh all pistons.
* balance the rotating assembly
* clean and magnaflux heads to check for cracks
* machine as necessary

Assuming you are going to assemble the engine your self you are done with the machine shop.
 
My builds detailed a little more than Dave's above...
- clean inspect, check block, heads, crank, rods for cracks or damage.
- Block: fit studs or new bolts, align hone mains, bore, plate hone, square deck to provided spec for finish and deck height. (optional: clearance for stroker crank, deburr, drill oil passages, tube right/left lifter galleries, install lifter bore bushings, final wash block, install and clearance cam bearings, freeze plugs, oil system pipe plugs, assemble short/long block or complete engine including figure compression ratio, degree cam, verify lifter rotation, provide spec sheets )
- Crank*: check for straightness, index/correct stroke, grind journals, polish/chamfer journals
- Rods*: Match length, install ARP bolts, resize big end, pin hone small end
- * internally balance assembly
- Heads: replace seats/guides as needed, cut guides for positive seals and retainer clearance, cut spring seats as needed(double springs), 5 angle performance Serdi valve job, set spring installed heights, assemble heads

A few notes, the blueprinting steps always cost more. The internal balancing on most Mopars is the same cost as external...except cast crank engines the need Mallory metal. A good valve seat machine will need new guides in 95% of the jobs. So figure on guides at minimum, 8 unleaded seats in most cases too. Align boring IMO is a necessary step. Some blocks are ok with factory tolerances, but if your shop uses a BHJ fixture or has a Rottler type plate/table, the main bore align honing will guarantee the bores and deck surfaces are the best they can be because the machines index off the crank centerline. Anything is better in most cases than factory machining in terms of quality. Any shop that doesnt give you a multi page spec sheet for your engine should tell you why they dont want to. It's easier for them to skip a few steps and not have to document the work. But that guide can be very helpful for you later.
 
FWIW, the cost to have my block and crank done per my notes was $1300, the shop specializes in race engine work and does the engines for the IHRA Top Alchol Funny Car "The Cape Codder". That included them painting the block and a CD of pictures at every step. I did not have them do any head work since my son got me the heads from the dealership he works at.
 
Dave, is that a race engine you have or street? The reason I ask is, that seams like a pile of money for a street engine that doesn't really get beat on.

Jack
 
wow, i called the 3 places here on the island and went from 3500.. to 2100.. to 1500.. now i have to decide who even knows what they are doing and what do i ask to make sure is getting done.. i love the idea of the cd with pictures, it just give your proof that this and that actually happened..

anyone wanna come with while i go and drag my block all over town trying to find the right guy to rebuild it?

haha

oh all the quotes were for the same thing..

basic rebuild..

bore and hone
replace this replace that.. its all french to me...
with a 340 cam
paint block..
150.00 extra for hardned seats
335.00 extra for balancing

what should i do.. do you think thats pretty good since its my only option..??
 
JB Precision built mine. I would guess that the prices you got have totally different amounts of machine work included, not everyone Magnafluxes so it may be included in the high bid but not in the lower ones. Same goes for parts, the low bid is probably a bare bones parts list.
 
right now jb on oak is the most exspensive one..

cords in langford is the middle.. the one im leaning towards.. now i have to ask him all the questions..

but i was just offered by a customer that comes in here who does this for a profession..

j&m racing??
jim..

hes in here(napa) like every 20 mins..

funny/good guy.
 
They're probably the most expensive because they are the most extensive, so no stone is left unturned. If you go to the cheap place odds are they'll keep adding costs along the way, their quote was for the basic buildup, we thought we could re-use this and that, blah blah blah. J&M racing, Jim, hmmm, that sounds familiar, that might just be the guy my chiropractor (major gearhead) knows, if so, he had lots of good things to say about the guy. I think he's a chebby guy but it's all the same when it comes down to it.
 
Coyote Jack said:
Dave, is that a race engine you have or street? The reason I ask is, that seams like a pile of money for a street engine that doesn't really get beat on.

Jack
Click to expand...

Street Engine! No one item was out of line on cost but they weren't the cheapest around but there is no question on the quality of the work either.

Clean (bake and soda blast), sonic check, magnaflux and measure the block was $200

Clean, measure, magnaflux, turn/polish the crank was $225

Measure and balance the rotating assembly (I used new rods would have been more with stock because they would have need some balance work) was $275

Deck & square the block, bore for 0.030 over with final hone using deck plates (the mains did not need to be line honed but were checked) and install cam bearings was $575

Can't imagine that you could do a whole bunch better at a reputable shop.
 
Since this is along the same line, I figured this was a good place to ask. Can anybody here recommend a good shop in the Sioux Falls, South Dakota area? I have a 340 that was disasssembled years back & the block has some rust in it. It will need cleaned, bored, etc. I want deck plates used when it's honed, if the mains need honed I'll want that done too. I'll want it balanced. All of the usual stuff for a good rebuild. Sioux Falls is a little over 100 miles from me but that is doable for a good job, especially if it's just one trip out & another to bring it home. The last shop I had do an engine Jeep) told me repeatedly that it would be ready & I made several trips, 60 miles each way, & had to stay on them just to get things done.

Another question. If there isn't somebody close, is there a reputable shop that somebody can recommend that I could send my parts to & trust to do what is needed & send them back? Somebody that I don't have to hold their hand to make sure they're doing what I need done? I figure I'd probably pay at least $100+ in shipping, but I'd pay close to that in gas driving back & forth.
 
Coyote Jack said:
Hey moper, just out of curiosity, what would all that machining cost? Just a ballpark figure.

Jack
Click to expand...

Here's what I (and my customers) pay:
disassemble/wash/mag block- $150
deburr and airless shot block - $125
disassemble and mag heads- $100
measure, wash and mag crank/rods- $50
fit bolts/studs and align hone (not including fitting caps or doweling)- $300 (includes cost of parts)
bore/plate plateau hone - $325
square deck - $250
index, grind,polish crank $325
internal balance (no mallory included) $250
resize rods (includes ARP bolts) - $150
performance valve job - $325
mill decks beyond clean up (to set chamber size) $75/head
mill intake flanges or intake $70
Assemble complete engine w/spec sheet - $500
Total is $2850 without needing heavy milling on the head surfaces. To be honest, I can cut come off that easilly. My blocks I sell magged and ready to machine for $300. Many engines are not re-using cranks or rods. By disassembling and bring in just the cores you can save a little too.

The thing is, all operations correct for factory based issues. I hear a lot of "that's a race engine deal..." It is a performance call. Good performance means more than 600hp. It means smooth operation, long service life, no future probelms after the install, better gas milage, better emmissions if you need to worry...And it means more power. Lifter bore bushings are definately more race oriented. But if you've ever had persistant low oilpressure from worn lifter bores, you also see its a repair for a block that would be tossed otherwise. Square decking as opposed to std milling gives you a correct quench distance, matched performance from each cylinder, better gasket sealing over the life of the engine on both head and intake, less valve train noises from pushrods being a hair too long or short...etc etc. I had a deck on a 340 that had been rebuilt. It was .028" different from end to end. If you had .040 preload on the front lifters, the rear would have .060. That can cause a cam to be wiped out. All because the miller used years ago wasnt used by a skilled machinist. Play with a calculator and see what the dfference .028" makes in compression. The front hole is .4 of a pt lower than the rear. If this had detonation problems on pump 92 and you couldnt figure it out, you'd be swapping cams, changing igitions, or mixing in race gas. Not to mention the intake sealing against oil and crank case pressure for more than a few hundred miles. There is a lot to be said for dropping ina new engine and needing only to set up carb and timing and change oil. An aweful lot of issues we read about over and over are the result of cutting costs during a build, and having to do things over or replace damaged parts after the fact.
 
moper said:
Here's what I (and my customers) pay:
disassemble/wash/mag block- $150
deburr and airless shot block - $125
disassemble and mag heads- $100
measure, wash and mag crank/rods- $50
fit bolts/studs and align hone (not including fitting caps or doweling)- $300 (includes cost of parts)
bore/plate plateau hone - $325
square deck - $250
index, grind,polish crank $325
internal balance (no mallory included) $250
resize rods (includes ARP bolts) - $150
performance valve job - $325
mill decks beyond clean up (to set chamber size) $75/head
mill intake flanges or intake $70
Assemble complete engine w/spec sheet - $500
Total is $2850 without needing heavy milling on the head surfaces. To be honest, I can cut come off that easilly. My blocks I sell magged and ready to machine for $300. Many engines are not re-using cranks or rods. By disassembling and bring in just the cores you can save a little too.

The thing is, all operations correct for factory based issues. I hear a lot of "that's a race engine deal..." It is a performance call. Good performance means more than 600hp. It means smooth operation, long service life, no future probelms after the install, better gas milage, better emmissions if you need to worry...And it means more power. Lifter bore bushings are definately more race oriented. But if you've ever had persistant low oilpressure from worn lifter bores, you also see its a repair for a block that would be tossed otherwise. Square decking as opposed to std milling gives you a correct quench distance, matched performance from each cylinder, better gasket sealing over the life of the engine on both head and intake, less valve train noises from pushrods being a hair too long or short...etc etc. I had a deck on a 340 that had been rebuilt. It was .028" different from end to end. If you had .040 preload on the front lifters, the rear would have .060. That can cause a cam to be wiped out. All because the miller used years ago wasnt used by a skilled machinist. Play with a calculator and see what the dfference .028" makes in compression. The front hole is .4 of a pt lower than the rear. If this had detonation problems on pump 92 and you couldnt figure it out, you'd be swapping cams, changing igitions, or mixing in race gas. Not to mention the intake sealing against oil and crank case pressure for more than a few hundred miles. There is a lot to be said for dropping ina new engine and needing only to set up carb and timing and change oil. An aweful lot of issues we read about over and over are the result of cutting costs during a build, and having to do things over or replace damaged parts after the fact.
Click to expand...


Looking at those numbers it doesn't seem so bad. If you took your basic 360 block, assuming that it is good, added a stroker kit ($1400), a set of Eddy heads ($1400) and add a good cam package you should be able to have a pretty stout engine in the $5000 to $5500 range. That is also assuming that you have the other goodies like intake ,carb. headers and ignition to start with.


Jack
 
It's all the small items that will add up. You'll need pushrods...and some type of rocker/shaft system. You still need block hardware and cam bearings, fuel pump eccentric or block off plate, tin (oil pan, timing cover, valve covers...it all adds up fast. but from what I've done...A non standard stroke engine needs the all the same parts plus a little, and all the same labor plus a little. So a 360 is around $5K. A 408 will be about 15% more. 20% more stroke for 15% more money??? Such a Deal!
 
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