1970 Challenger Restore Planning Phase

[NoMope Greg]

A Hemi is an engine with a hemispherical combustion chamber, as opposed to a wedge-shaped combustion chamber in the head.  The advantage is that it allows the valves to be positioned in such a way to give incoming air a straighter shot into the engine and allows the spark plug to be centrally located.  The disadvantage is that the valve gear is generally more complicated and combustion at lower engine speeds may not be very efficient.  Lots of manufacturers have built hemis; Chrysler just trademarked the name.

Here's a Hemi head (From this site: http://www.classichemi.com/hemiwhat.shtml)  Notice the circular and smooth shape of the combustion chamber.)


Here's a Hemi piston.  You can see how it fits up into the rounded combustion chamber:


Here's a wedge-head combustion chamber.  Most domestic engines V8s use wedge heads.  They mostly fall into one of two categorier - open-chamber or closed chamber.

This is an open-chamber head.  Notice how the shape of the chamber is flatter than the hemi head, with a deeper recess around the valves.   Notice also how the spark plug comes in from the side.


This is a closed-chamber head.  Notice that the recessed are is all that seems to be there - the open circle part of the chamber is machined flat.  This offers better combustion because all of the incoming mixture is kept in a more confined area near the valves and the plug.


Wedges use either flat top pistons or quench-dome pistons.  I'm sure you know what a flat-top looks like; here's a quench piston:

[geminiviper]

Ah...  I see.  Cool info, thanks.  From what I gather I can get just as much of a beast of an engine from a 440 stroker bored out as I could from a Hemi.  And probably for cheaper too.

So here's kind of what I was thinking of doing.

Starting with a 440 block.  I'm not sure how far to bore it out but we'll talk about that later.
www.440source.com has a 440 block already machined and bored for about $1300.

Stroker Kit for about $1900
http://www.440source.com/strokerkits.htm
Kits include crank, rods, pistons, pins, locks, Clevite main bearings, Clevite rod bearings, Total Seal file fit moly rings, AND precision final balanced.

Intake manifold from Edelbrock
http://www.eautoworks.com/product-JG-Edelbrock-198065.htm

Heads from 440 source
http://store.440source.com/Stealth-Aluminum-Cylinder-Head-COMPLETE-SINGLE-HEAD/productinfo/200-1055/

A fuel injection system from either FAST or Mass-Flo.
http://www.fuelairspark.com/ezefi/
http://www.massfloefi.com/mass-flo-systems-chrysler-c-1_8/chrysler-big-block-efi-system-p-15

What do you guys think?

[NoMope Greg]

Seems like a decent plan.  BTW - notice that the Mass-Flo system comes with a manifold included in the kit.

Boring is determined by the wear in the cylinders and is only done to get a fresh perfectly circular cylinder for the rings to seal against.  The less boring that has to be done, the better, for cylinder wall integrity.  Most engines won't tolerate more than 0.060" (about 1.5 mm) of overbore  anyway.  The big increases in displacement come from stroking the engine - installing a crank with a longer stroke.  Boring a 440 by 0.060" (commonly called "60 over") only nets you about 12 cubic inches of displacement, versus the 72 cubic inches with the 512 stroker crank.

[femtnmax]

I think you have great ideas. The project would keep you busy for sure.  All the responses on your posts have been correct.  There have been points made for the pros and cons.
Are you willing to spend A LOT of time away from you wife and child???  Are you willing to spend at least TWICE what the car will be worth if you had to sell it???
My dad worked very hard, put in long hours, then he died very young.  We never got to connect because he was too busy to spend any time with us kids.  I wish we could have spent more time together.  I never got to really know him.
I'm an ASE certified mechanic, I'll tear into anything mechanical.  I bought a Chally with decent body, needed some panels replaced, etc, and figured I'd do all the wrenching and some of the body work.... As commented on this forum, the cost to restore these cars has doubled or tripled in the last half dozen years.  My estimate for doing my car with a small block V8, no stroker, nothing fancy...well the actual cost is way past what I estimated.   I will probably have $10,000 to $15,000 into the car over what it is worth.  That means if wrecked or stolen, you may never get your money back.
I looked into the collector car insurance.  Yah they will insure it for the money you've spent on it, but every one of them put limits on how many miles you can drive.   That won't work for me.  I want to drive the thing.
A comment about big blocks, especially strokers.  Think about the fuel economy.  Jay Leno says the gas gauge on his hemi car moves at the same rate as the minute hand on the clock.  And the traction is so poor....read big torque and horsepower.  He said its no fun to drive...you can never really get on it without the car getting real squirrely on the road.  I had a bone stock 440 GTX many years ago.  When you punched the gas pedal, if the tires hooked up on the pavement not just right the car was sideways quicker than you could snap your fingers.
More than one person on this forum has said to buy the most car you can for the money.  With the bad economy right now there are some killer deals out there.  Maybe buy a driver you can tinker on and still learn, rather than a money and time pit that you hope to drive someday.

[mopar12372]

my openion (not to be harsh)-> go buy one thats already done and drive it if you have the money. sell what you have if you have one that seems to be a better reality for you .

[geminiviper]

Thank you for your opinions.  They are noted well.  I don't have the money to buy a restored  car, and I'm not going to finance one so I'll stick with this option. 


Side note, I talked to the sellers son and asked if I could get some pics and the VIN so we'll see.  If he sends it I would think it will be Monday I get it.

[TROUBLE987]

i got a www.carolinamachineengine.com i built the motor 10 years ago when i worked there and it went 13.0-12-9 in the quatermile you can order one of there crate motors and it would be cheaper than building what you are wanting..in less your going over 650 hp i would,but if you are,i wouldnt build a 440-go hemi or low deck 400 stroker..just my 

[geminiviper]

I'm sure, at least some of, you have heard of the method of converting a 440 block to a hemi.  What are the drawbacks and benefits to doing this?  I understand from reading the articles that it can be a bit complicated and needs to be done with a high degree of accuracy.  If I were to buy a 440 block for dirt cheap would it be worth my time and effort and money to convert?

In the chat room I asked about the HP benefits of boring, the response I got was about an increase of 5-10 HP per 0.030 over.  Was that 5-10 per cylinder or or total?  So if it's an 060 over would it be approximately 160 HP increase or would it be around 40 or 50?

Would it be worth it then if I'm going to have the block machined for the Hemi conversion to have it bored out while it's there? 

Still waiting on pics...   

[barracuda7199]

but you don't want to bore the block anymore than you have to. thick rigid cylinder walls make more power. the hemi conversion gets expensive!!! haven't seen one of them in a while either.

[Sean]

Hey Ben!  Great to see someone else from the base on th forum!  I work out at Scott for the AFNIC.  I have a Cuda that I'm restoring and am in the early stages of it.  Check out the link in my signature block for the blog I started documenting the resto.  I'm in Iraq right now, due to be home in a month. 

You said the car is in primer and ready to paint.  I would ask what has been done to get it to that point.  What sheet metal has been repaired/replaced.  What kind of primer was used (regular or epoxy).  Was the car taken down to bare metal or is the existing paint still under there.  Is the car still wearing the original paint?  If the existing paint is still there and primered over, you don't know what's underneath it.  I've heard that many shops wont paint cars that they don't prep and primer thmselves.  Leaves them open to too many unknowns.   I'd hate to see you get the car painted and then find out that the proper prep work wasn't done.  Also, if your looking to push that kind of HP, you may want to ensure that torque boxes or frame rail connectors are put in to keep the body from twisting.

Maybe if you let the board members know when and where you are going to look at the car someone can help you look the car over and provide you a no BS evaluation of what the car.   

I'm pretty new to the resto thing too.  I do have some mechanical knowledge, but it's not what I'd consider extensive.  I'd say I have 100's of hours into researching what and how I'm going to build my car.  And I haven't really been looking into engine/trans, driveline, and the interior yet, just the body.  I'd recommend talking to folks on forums like you have done right here and do all the research you can.  Research and Planning - do those two things and you will save you time, money, and heartache in the long run.

When I get back, I'll look you up and we can get together for a cold one!

Sean

[NoMope Greg]

but you don't want to bore the block anymore than you have to. thick rigid cylinder walls make more power.

   The best way to make more power through increased displacement is with a stroker crank.  Boring a 440 out to max bore offers a total of about 12 cubic inches over the stock bore.  Installing a 4.150" stroker crank in place of a stock 3.750" will get you an extra 60+ cubic inches.  Of course, there are other considerations when building a stroker - clearances, rod length, piston choice, etc - but 440 Source and others will sell you a kit that takes all the guess work out of the build.  Or, as several others have said - get a crate engine and take all the guesswork and other headaches (like finding a good machine shop) out of the equation.

The company that offers the Hemi conversion parts for the 440 block is Stage V Engineering.  You can find it here: http://www.stagev.com/pages/hcheads.html.  Unless you really want a Hemi-headed engine, for the power or for the visual impact, I think you're better off staying with the standard wedge head (probably Edelbrock Performer) and work on making the total package work well together.  You can make  lots more power than you'll ever use without the trouble of converting to a Hemi.

[geminiviper]

Thanks guys.

Sean,  stay safe out there buddy.  I know full well how it can be out there.  I just got back from Balad Christmas Eve. 

For a while I probably won't have the money to just go buy a crate engine.  On the budget I live on, it will likely be a part by part experience for a while.  So we'll see.  I'm only asking these questions because it's part of the homework process.  If I can get an engine that is all good that needs no machining then I'll stick with not doing it.  I still plan on doing a stroker I'm pretty sure. 

[TROUBLE987]

  The best way to make more power through increased displacement is with a stroker crank.  Boring a 440 out to max bore offers a total of about 12 cubic inches over the stock bore.  Installing a 4.150" stroker crank in place of a stock 3.750" will get you an extra 60+ cubic inches.  Of course, there are other considerations when building a stroker - clearances, rod length, piston choice, etc - but 440 Source and others will sell you a kit that takes all the guess work out of the build.  Or, as several others have said - get a crate engine and take all the guesswork and other headaches (like finding a good machine shop) out of the equation.

The company that offers the Hemi conversion parts for the 440 block is Stage V Engineering.  You can find it here: http://www.stagev.com/pages/hcheads.html.  Unless you really want a Hemi-headed engine, for the power or for the visual impact, I think you're better off staying with the standard wedge head (probably Edelbrock Performer) and work on making the total package work well together.  You can make  lots more power than you'll ever use without the trouble of converting to a Hemi.

i think the hemi conversion is not a good idea at all,first of all a true 426 hemi is made to turn..if you dont turn them they are worthless..if you do a wedge hemi..it will have ok power but a 440 is not built on the bottom to handle rpms..the 426 hemi motors are..thats the biggest down fall to the conversion...now dollar for dollar a wedge can be built much cheaper,than a hemi..and will run circles around a hemi..now if money is no object,HEMI+BLOWER=BEAST...NO OTHER MOTOR HAS DONE WHAT THE HEMI HAS DONE,IT FEARS NOTHING WITH A BLOWER..AND Oh just so you know the motor is not to bad naturally aspirated either..its only the fastest s/s motor in the world..and no other engine can even run with it,so its got its on class in NHRA SS/AA,TopFuel funny car,TOPFuel dragster,if they allow a true hemi engine to run in its class,it dominates plain and simple..so either go true hemi,go wedge..not the wedge hemi..you can get those in todays cars..lol..they are 5.7-6.1-6.4.. :roflsmiley:good luck

[geminiviper]

Thanks Trouble.  That was pretty much the kind of information I have been looking for.

[geminiviper]

Well, so something sounded fishy with the deal, and it turned out fishy...  Apparently the guy wants a lot more for it than he said at first.  He seems to remember asking $2500 for it.  For the last year I have been told $600, saved the money, and spent or put away other monies so $2500 is out of reach for me.  Not having a project, and no projection for the project I'll bounce around this site and read up on what I can and learn the car ninja and engine jedi ways.  I'll let you know when I get a project or when I am in a position to buy one.  Thanks guys.