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Author Topic: Ready to build 512  (Read 3654 times)

Offline 73cudabr

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Ready to build 512
« on: October 31, 2016 - 05:35:39 PM »
Hi Team,

As some of you have read my engine came end of life a few weeks ago I've slowly been getting it ready to pull and should have it out of the car and down to the bare short block this weekend. Then it's off to the machine shop. So I've scoured the internet and this forum, and it seems that every engine build is unique to what we want and how we drive. I'm not the most technical person but I've been told some guidelines.

As most say - I'd like a street monster that is reliable, and able to be driven a lot. It seems that if I build a stroker, and set a rev limiter at 5500, I can have all my power in before that, and keep it plenty safe from not running it into the red line. Having a aggressive cam that lets people know it means business would be great, but don't know how big I can go to keep it reliable. 

727 3 speed, 3:23 gear. Might look into adding an overdrive add on if thats a thing. It was suggested but I have not looked into it yet.

512 stroker kit - A few options here. I've seen on youtube and have heard a lot about 440 source. I also have heard suggestions for Muscle Motor's as well. The prices are pretty close to identical. Thoughts?

Edelbrock Performer intake - I already own this, not sure if it's good or bad for this build? Any suggestions?

Holly DP 750 - Everything I see this may be too small for this build? Thoughts? Can I get away with it or should I go bigger for my goals? Will I loose drivability by going bigger?

Heads - Need to purchase. Unless told otherwise I'm thinking super stealth from 440source or Edelbrock. Should I have them machined more after purchase? Any other's to take into consideration?

Cam - Hydraulic Cam - Don't know much about them, just told it's more reliable and if my mechanic was building an engine he'd spend the extra money for this and the lifters up front.

Roller Rockers - Don't know much about these either, but I'm told it's free horsepower

Headman Headers - I own these already

MSD electronic Ignition - I own this already

Stroker Kit - $2200
Intake - 0
Carb - $200 +/_ (guessing I'd have to sell mine and move to a 950?. Don't know what I can get for a holly DP)
Heads - $900
Cam - $800 (lifters and cam)
Roller Rockers - $300?
Machine Shop - $600? - I have no idea what this costs?
Labor - I have a friend who is knowledgeable here

Conservatively I'm thinking 5 - 5500 for parts and machining. Again I have a carb to use or sell. I'm thinking a functional intake and headers. So I'm hoping I can save some coin there. I'f I'm way off on the machining costs then I"ll adjust, but I'm happy spending up to 7K for parts if that's what it takes to do it right. Suggestions are very much welcome. I'd like to dial this in so I can start budgeting this, and running parts by my buddy who is helping me.

Thank you in advance. I hope to be melting asphalt by Christmas and get some Dyno numbers shortly after it's installed.450 hp 500tq to the wheels would be great. My old beat up 440 made 250/308.

This is where i'm at currently. Going to get the flywheel and trans bolts off tonight. then it's one motor mount and ready to go.







Offline dave73chally

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Re: Ready to build 512
« Reply #1 on: October 31, 2016 - 09:03:47 PM »
There are a few 512 recipes on here. Look for anything by chrycho psycho and you can't go wrong. I posted mine a few posts as well as a startup video.

Your machining costs look way low unless you're doing a lot yourself? Mine were about 2600 for bore, hone, hot tank, sonic check, rotating assembly balancing and full assembly of a short block
73 Challenger
512 / 4spd / Hotchkis & QA1 Suspension

Offline 73cudabr

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Re: Ready to build 512
« Reply #2 on: October 31, 2016 - 10:04:17 PM »
There are a few 512 recipes on here. Look for anything by chrycho psycho and you can't go wrong. I posted mine a few posts as well as a startup video.

Your machining costs look way low unless you're doing a lot yourself? Mine were about 2600 for bore, hone, hot tank, sonic check, rotating assembly balancing and full assembly of a short block

We will need all but the assembly of the short block. We plan on doing that. Of course I'll likely be doing a lot of spectating for that. Breaking things down is one thing. Putting it back together is another. I'd imagine a lot of the labor was in assembly? I'll account for more so I'm not surprised when I start talking to shops next week.


Offline 1 Wild R/T

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Re: Ready to build 512
« Reply #3 on: October 31, 2016 - 10:24:31 PM »
First the carb....  Yes strokers like more carb... But... You have a 750, it will work for now, you ask about a smaller carb hurting driveability, actually a smaller carb is better for normal around town driveability, it's weak point is big RPM's & wide open throttle... Up to 4500 it'll scream, to 5K it'll be close to a 850-900 cam carb, over 5K it'll be hurting you...   FWIW according to the math 733 CFM carb will feed a 512 CI engine at 5500 rpm's... Assuming 90% volumetric efficiency which honestly is very optimistic, typically a street engine will be in the 75-80% range  At 80% you only move 651 CFM.... But that means it's absolutely done & has run out of air.... Anyway for now, save you $$... :2cents:

Next Roller Rockers... Any set you buy for $300 will be junk & likely to cause more harm then good.... There are tiny needle bearings that tend to escape the rockers & they do ugly harm to other engine parts when they get out...  The good Chinese roller rockers are $500 & American made close to $800... Personally I strongly prefer old school non-roller Ductile Iron Rockers, Isky if you can find them, if you can't Crane makes a decent piece too & they are much easier to find...

Heads, there have been some very good heads popping up for Mopar Big Blocks in the last few years... Trick Flows are one of them, there are other good options...

Cam, at $800 your high for a standard flat tappet hydraulic but low for a hydraulic roller....  And then you'll need allot of other parts... They do add up...  On the other hand standard flat tappets have a bad habit out going flat & when that happens often there is allot of additional damage....
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Offline HP2

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Re: Ready to build 512
« Reply #4 on: November 01, 2016 - 09:21:04 AM »
I'd agree you're a bit low on some parts and real low on machining. I'd say a build of this sort is going to be closer to $8-10k depending on how trick you get with components and how much work you can do yourself/with assistance.

Do you know what crank/rod combo you currently have?  While not as sexy as 512, a clean up on the crank and rods with a good compression height piston can put a 440 stock stroke into a pretty high power level. Then you choice of heads will actually be able to supply the  needs of the engine. I don't think the Stealth or Ebrocks are up to supply 512 inches at higher rpm.

Offline 734406pk

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Re: Ready to build 512
« Reply #5 on: November 01, 2016 - 06:33:24 PM »
Muscle motors offers a 505 short block, machined, assembled and ready for cam/heads etc... Perfect for a DIY build!
http://www.musclemotorsracing.com/bb-short-block-description
1973 Challenger 440 6 pack auto 3.91 rear
2012 Dodge Ram 3500 dually 6.7 Cummins Fleece EFI Live
1973 Challenger 318 2bbl auto 2.73 rear 22.5 mpg RIP
1970 Challenger TA 340 4bbl auto-Sold and sad
1999 Dodge Ram 3500 dually 5.9 Cummins Fleece tuned VGT-sold
1995 Kawasaki ZX1100E & still alive

Offline 73cudabr

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Re: Ready to build 512
« Reply #6 on: November 01, 2016 - 10:54:24 PM »
Muscle motors offers a 505 short block, machined, assembled and ready for cam/heads etc... Perfect for a DIY build!
http://www.musclemotorsracing.com/bb-short-block-description


Thats not a bad idea...5 grand for a 505 block. Heads and a cam and i'm all done! I think?

Offline Chryco Psycho

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Re: Ready to build 512
« Reply #7 on: November 01, 2016 - 11:36:31 PM »
I agree with most here
 Heads & Cam will make or break the build / engine , the cam Has to match you needs Not sound , heads I would use a better head then Eddy , there are a number of good choices right now , closed heart shaped chamber with smaller CC is better all round as you can still use flat top or dished pistons & maintain needed compression to compensate for heat loss to alum . This is a bad place to save $$
 The cam is the most critical part of the combo you have 4 choices , hyd Flat tappet or hyd roller / solid flat tappet or solid roller coat will vary rollers are not cheap . Also a bad place to save $$
You need to decide on gear ratio / overdrive so the cam will match one thing that really doesn't work is having  a cam thet starts to work at 2600 rpm & you are running 220 rpm @ cruise speed on the highway so the engine is lugging with OD . .
 750 will work for now , intake is a good choice , Holley Street Dom is good also & sits lower .
I agree with Iron rockers or Cast Stainless such as PRW that are bushed not needle brg .
 I would expect $7k as a minimum using most of the parts you have
 You may learn to hate Hedman headers too

Challenger - You`ll wish You Hadn`t

Offline 73cudabr

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Re: Ready to build 512
« Reply #8 on: November 02, 2016 - 11:16:17 AM »
I agree with most here
 Heads & Cam will make or break the build / engine , the cam Has to match you needs Not sound , heads I would use a better head then Eddy , there are a number of good choices right now , closed heart shaped chamber with smaller CC is better all round as you can still use flat top or dished pistons & maintain needed compression to compensate for heat loss to alum . This is a bad place to save $$
 The cam is the most critical part of the combo you have 4 choices , hyd Flat tappet or hyd roller / solid flat tappet or solid roller coat will vary rollers are not cheap . Also a bad place to save $$
You need to decide on gear ratio / overdrive so the cam will match one thing that really doesn't work is having  a cam thet starts to work at 2600 rpm & you are running 220 rpm @ cruise speed on the highway so the engine is lugging with OD . .
 750 will work for now , intake is a good choice , Holley Street Dom is good also & sits lower .
I agree with Iron rockers or Cast Stainless such as PRW that are bushed not needle brg .
 I would expect $7k as a minimum using most of the parts you have
 You may learn to hate Hedman headers too

Thanks for the suggestions everyone. I'll likely go dark until next week when the engine is out and broken down. It also appears I have a lot to learn about how parts work together on the build so I ordered a few books "Big Block Mopar Engines (how to rebuild) by Don Taylor, and "How to Build Max Performance Mopar Big-Blocks" by Andy Finkbeiner. Hopefully I can pick up some detailed information and have a better understanding of why you all are making the recommendations that you do. Then I can also take responsibility for the end result good or bad. I guess if I'm going to spend this much money, I should know why I'm spending it, and make sure it's right.


Offline 734406pk

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Re: Ready to build 512
« Reply #9 on: November 02, 2016 - 11:21:30 PM »
Thanks for the suggestions everyone. I'll likely go dark until next week when the engine is out and broken down. It also appears I have a lot to learn about how parts work together on the build so I ordered a few books "Big Block Mopar Engines (how to rebuild) by Don Taylor, and "How to Build Max Performance Mopar Big-Blocks" by Andy Finkbeiner. Hopefully I can pick up some detailed information and have a better understanding of why you all are making the recommendations that you do. Then I can also take responsibility for the end result good or bad. I guess if I'm going to spend this much money, I should know why I'm spending it, and make sure it's right.


Excellent idea! Do your research before spending on the wrong components, you want to do this build only once! The transmission and drive train will need to be addressed as well to withstand the extra HP. How are the brakes BTW?
1973 Challenger 440 6 pack auto 3.91 rear
2012 Dodge Ram 3500 dually 6.7 Cummins Fleece EFI Live
1973 Challenger 318 2bbl auto 2.73 rear 22.5 mpg RIP
1970 Challenger TA 340 4bbl auto-Sold and sad
1999 Dodge Ram 3500 dually 5.9 Cummins Fleece tuned VGT-sold
1995 Kawasaki ZX1100E & still alive

Offline 73cudabr

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Re: Ready to build 512
« Reply #10 on: November 03, 2016 - 10:05:46 AM »
Thanks for the suggestions everyone. I'll likely go dark until next week when the engine is out and broken down. It also appears I have a lot to learn about how parts work together on the build so I ordered a few books "Big Block Mopar Engines (how to rebuild) by Don Taylor, and "How to Build Max Performance Mopar Big-Blocks" by Andy Finkbeiner. Hopefully I can pick up some detailed information and have a better understanding of why you all are making the recommendations that you do. Then I can also take responsibility for the end result good or bad. I guess if I'm going to spend this much money, I should know why I'm spending it, and make sure it's right.


Excellent idea! Do your research before spending on the wrong components, you want to do this build only once! The transmission and drive train will need to be addressed as well to withstand the extra HP. How are the brakes BTW?

Brakes work - but will need upgrading, likely the suspension as well. Thats the next forum thread I plan on digging into after the engine is out. Should be a good time do that with all the room.

Offline 73cudabr

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Re: Ready to build 512
« Reply #11 on: November 14, 2016 - 06:27:04 PM »
Getting closer. Stroker kit and machining coming next.






Offline 73cudabr

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Re: Ready to build 512
« Reply #12 on: November 20, 2016 - 09:08:43 PM »
taking it to the machine shop tomorrow. And Yes I own a Lincoln town car as my DD, and yes the trunk can likely fit two engine blocks! I've posted a closer look at what I'm thinking of buying. Likely start placing orders Wednesday. Any suggestions are appreciated. I know some may have feedback around heads and my EFI choice. Thinking EFI to make tuning easier/no fuel smell/better fuel milage.

Based on the old adage of 1.25 pound of tq per cubic inch on a quality build I'm shooting for 630 ft pounds of TQ. Which should put me around 650HP at 6000 RPMs at the flywheel. Again - Speculation, but time will tell.

    10:1 Compression / 505 Stroker W/440 block/3.23 gears 3 speed 727 tq flight
      ○ Operating Range - 2500RPM - 6000 RPM (rev limiter based on peak HP)
      ○ I have Performer RPM Intake Already
      ○ Total Cost - $8500 Apprx


440 Stroker kit w/extra lite crank - $2349

CNC - Machined stealth heads (gaskets/ARP Bolts) - $2300

Comp Cams Hydraulic Roller - $320
     .549/.544" lift and 242 intake and 248 exhaust duration at .050

Comp Hydraulic Roller Lifters - $550

Roller Rockers - $300

FiTech EFI 800HP Kit (HP Pump/Lines) - $1500

Misc crap that will add up- $400

Machine Costs (hot tank/Sonic check/bore/hone) - ?
                     







Offline twalker

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Ready to build 512
« Reply #13 on: November 20, 2016 - 09:42:19 PM »
What rockers are you using?  I just finished building my 512.  My roller rockers were $900usd, Harmon Kardon S70015KE. 300 sounds low. 

Trickflow heads on mine.

Following your thread as I'm curious about the FI system.  I have a proform 850 on now.


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« Last Edit: November 21, 2016 - 04:06:46 PM by twalker »

Offline 73cudabr

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Re: Ready to build 512
« Reply #14 on: November 20, 2016 - 10:55:35 PM »
What rockers are you using?  I just finished building my 512.  My roller rockers were $1000USD, Harmon Kardon 1500ske.  300 sounds low. 

Trickflow heads on mine.

Following your thread as I'm curious about the FI system.  I have a proform 850 on now.


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Most likely low - I have not ironed those out yet. I'll research them and up my price point. I'll also check the harland sharp rockers. Hoping to have it together by Christmas.
« Last Edit: November 20, 2016 - 10:58:03 PM by 73cudabr »