Bottom End Shocker Build

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67autocross

67autocross

A new iron curtain drawn across the 49th parallel
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Okay seeing that my much maligned “free cam build” didn’t go over here as well as my other engine builds like the “old school 340 build “ and the “ mild magnum 360 build “….I think it’s time to leave that free cam build off this site until some of you are more mentally prepared for it… now that does not imply that this Bottom End Shocker Build is going to follow all engine build conventional thinking…but it might be a bit closer to normal than the mild magnum was…

So here is the parts list…and unlike my other builds I will try to post prices(Canadian dollars)and part numbers

Stock bore 340 block $100
Mopar Caps $400
ARP main studs $150
Scat forged 4 inch crank $1000
Rods TBA
Pistons TBA but will be in the 10:1 range with some quench
Heads are Promaxx Shockers CNC ported…. But they will get some additional porting and valve work
Cam will be a solid lifter custom grind
Intake will be an Ed Airgap dual plane that may see some hogging

So keep in mind that this is not going to be some drag strip bracket engine that needs a 4500 stall and 4:10 gears to pull away from the stoplight…. I want the bottom end torque of a big block and peak power at 5500rpm…

as always any input is truly appreciated….but I will still do it my way in the end!
 
missing linc said:
Where the heck did you find a standard bore 340 block for $100?
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Some guy brought them into a local machine shop but he lost/sold the main caps off them…so I bought them because he had more blocks with caps…and he didn’t want to pay for a line bore…
 
$100 for the block, $400 for the caps...about right. Add a >$200 line bore and badabam...$700 block...but its got a straight bore.
 
pishta said:
$100 for the block, $400 for the caps...about right. Add a >$200 line bore and badabam...$700 block...but its got a straight bore.
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I’ll post the price of the line bore when it gets done... but in Canada they won’t unload the block from your truck for $200…
 
67autocross said:
Some guy brought them into a local machine shop but he lost/sold the main caps off them…so I bought them because he had more blocks with caps…and he didn’t want to pay for a line bore…
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I have about the same. Standard bore block with mismatched caps for $100us. I found set of two bolt caps from an R block for $100, so I'll go through with a line bore and such. Looking forward to your progress.
 
mygasser said:
he sold you more than one at that price??? :wtf:[/

The blocks actually belonged to the machine shop…the guy who brought them in just left them because he didn’t want to pay the bill for hot tanking them…they said there might even be a third block somewhere in the back…they have been there for years…I told them who to call if they find it…
I know a couple of years ago a guy picked up a 340 block at another machine shop in town when the owner was retiring…I heard he paid $300 and it had main caps
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gzig5 said:
I have about the same. Standard bore block with mismatched caps for $100us. I found set of two bolt caps from an R block for $100, so I'll go through with a line bore and such. Looking forward to your progress.
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Honestly without caps they are really only worth $100…especially in Canada as machine shops probably charge $500 for a line bore…so you could end up with $1000-$1500 into the block by the time you are ready to assemble
 
67autocross said:
Some guy brought them into a local machine shop but he lost/sold the main caps off them…so I bought them because he had more blocks with caps…and he didn’t want to pay for a line bore…
Click to expand...

Thats so odd as I am beginning a build with a 340 block I acquired for free because of the exact same no caps scenario. J.R.

thumbnail_20210731_110500.jpg
 
67autocross said:
Honestly without caps they are really only worth $100…especially in Canada as machine shops probably charge $500 for a line bore…so you could end up with $1000-$1500 into the block by the time you are ready to assemble
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I charge a minimum of $500 for a line bore as well. A fully machined , ready to assemble block will easily be in the $1500 range. Totally agreed. J.Rob
 
i don't know if 318 caps fit, but if so wouldn't it be cheaper to get a 318 block with caps and use those on the 340 block? obviously not 4 bolt caps but unless it's a race build they're not really needed.
 
mygasser said:
i don't know if 318 caps fit, but if so wouldn't it be cheaper to get a 318 block with caps and use those on the 340 block? obviously not 4 bolt caps but unless it's a race build they're not really needed.
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.
You would think you could pull set of caps off of a 318 and throw them over on another block and have it align bored and honed. But it just doesn't work that way because the caps are mated to the block differently between blocks. As in the Caps maybe side shifted on one block compared to the other. Then you can either weld up the cap where it joins to the block and file fit the cap over or get virgin caps and fit them.
Plus 318 caps are smaller than 340 caps as in less beef.
Last set of caps I got were those four-bolt main ones like in that picture in that box. I think I got them from Rocket here on Fabo.
 
Jadaharabi said:
.
You would think you could pull set of caps off of a 318 and throw them over on another block and have it align bored and honed. But it just doesn't work that way because the caps are mated to the block differently between blocks. As in the Caps maybe side shifted on one block compared to the other. Then you can either weld up the cap where it joins to the block and file fit the cap over or get virgin caps and fit them.
Plus 318 caps are smaller than 340 caps as in less beef.
Last set of caps I got were those four-bolt main ones like in that picture in that box. I think I got them from Rocket here on Fabo.
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I got mine from Rocket also…if I was doing a stock 340 rebuild I would throw 318 caps on it…but I’m going for around 550hp and more torque…
 
That’ll work well at the strip even though that’s not the intended build - :poke:

Just get a new car on a serious diet and you’ll zoom along pretty good!
 
sweet, interested to see a build with the Promaxx CNC heads. Are they pretty nice? Hardware is good?
 
rumblefish360 said:
That’ll work well at the strip even though that’s not the intended build - :poke:

Just get a new car on a serious diet and you’ll zoom along pretty good!
Click to expand...

This 416 engine will end up in my purple beater….the 340 that is in now will get a refresh
 
cookietruck said:
sweet, interested to see a build with the Promaxx CNC heads. Are they pretty nice? Hardware is good?
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I don’t have the exact set of heads in my hands yet…Promaxx had one set show up available this week so my local shop who is their Canadian dealer ordered them….saying that I have a friend that has built at least 20 small/big block Mopars with them and they have all been great…I have looked at lots of them personally and can say are well made…saying that the old EQ heads could make the same power for half price
 
cookietruck said:
sweet, interested to see a build with the Promaxx CNC heads. Are they pretty nice? Hardware is good?
Click to expand...
I just put a set on a 10.5-1 - 340 w/a XL285HL on a 108. I’m a little ways from start up as there are other issues stopping me.

Ops… (EDIT….) I swap out stock port Edelbrock heads for these knock off’s. ProMaxx’s CNC job does leave some port work on the table but yet gets some good numbers out of them. The power gain even with the same cam was very good.

But yea I do like everything that it came with. I did do some work on the spring seat area for matching valve springs to the cam being used.
 
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I did some (Pittsburghracer) mods while I had them off the other engine. Just to get a little wider and what ever that offers. Which I have no idea…. LOL
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