Budget Build 5.9 for a 71 Scamp

[michiganpat]

You’re not building a race car. If 300hp is your goal, and you’re keeping the 2.xx gears just put a stock converter in it. Save the money. You’ll be much happier cruising to the ice cream stand. Now, if you jump up in gear, (like 3.23s or 3.55s) and you want a little more stop light to stop light gitty up then a good 2800 or so converter can make a big difference.

I disagree, the taller gears would benefit more from a higher stall, as the converter will flash higher and provide maximum torque multiplication more in the meat of the powerband at launch. you just don't want too high of a stall to where you'll have excessive converter slip at your typical cruise RPM. that's where a lockup transmission can be nice.

 

[TT5.9mag]

I disagree, the taller gears would benefit more from a higher stall, as the converter will flash higher and provide maximum torque multiplication more in the meat of the powerband at launch. you just don't want too high of a stall to where you'll have excessive converter slip at your typical cruise RPM. that's where a lockup transmission can be nice.

Tall gears and loose converters make for slow, un responsive vehicles.

If the engine is relatively stock, and the gearing is low (numerically) then stock converters work just fine. He’s not going to be “launching” this car. The intended use of the vehicle is the MOST important factor here.

 

[TT5.9mag]

Disregard that guy. He's obsessed with some **** he had twenty years ago. Every thread always gets side tracked to needing 200psi compression and 4.11s.


Bottom line is a mild cam will definitely wake up that motor. I have the exact same setup in my car. 5.9 magnum, stock everything with an oregon cams regrind, airgap, and stock manifolds. Runs great.

I had 2.76s and stock converter, which was pretty solid and a great highway cruiser. Went to 3.21s and a 2700 stall converter more recently. Woke it up, but much worse on the highway. You will be happy with your car either way.

See, this guy gets it. Excellent post with first hand info. THANK YOU!

 

[junkyardhero]

Ok guys… let’s all relax

AH-HAHAHAA!

surely you jest. this is FABO man... there is no "relax" setting for some of these loons.

 

[junkyardhero]

The intended use of the vehicle is the MOST important factor here.

this.

this times infinity +1

build around intended use of the car, not some bullshit pie in the sky bragging rights RPM limit, or HP number.

all of the criteria you laid out in your first post-- which clearly some people did.not.read. [names redacted]-- is easily attainable with a stock motor, stock stall, and the gears you currently have. add in a reground cam, whatever flavor of air gap you want to afford, and which ever brand of reasonably sized carb you are comfortable tuning.

there. done.

and within a reasonable budget too.

 

[JDMopar]

I don't remember seeing it mentioned in this thread...but I may have missed it. You will also need a 360 LA center sump oil pan and pickup to make the 5.9 fit your K frame. I think you have to use a combo of LA and Magnum oil pan gaskets, but I forget which way it goes. I "THINK" it's LA end seals and Magnum pan rail gaskets. Good luck on your build. Edelbrock makes a little red electric fuel pump that is quiet. A friend of mine has them in his old street rods and they work well. He did the Hot Rod Power Tour this year with his Model A and had no trouble.

 

[skep419]

1634 Oregon cam/Hughes 1199 spring kit, Ede air gap intake, Dougs D453's, Holley 750dp, 8 3/4 3.23's
Works good

 

[crackedback]

a little light reading on the morning commute to work today ... This is the portion of my subway ride where the train is elevated above the streets, with cars driving underneath. Once I cross the Williamsburg Bridge into Manhattan, the train goes underground.

This book tells you to check the cam centerline before you tear the engine apart completely. I hope I don't really need to do that?

View attachment 1716478092

If you are using the same pieces over from an unknown running engine, it's good to know where things were installed as a reference.

If you didn't, not the end of the world. Changing it out, not a concern.

 

[ScampNYC]

Thanks everyone for the hot debate.

The goal is streetable, as cheap as reasonable possible, as "easy" as reasonable possible, and with as much performance as we can eke out within those parameters.

It sounds like we have a plan:

• Stock motor, refreshed with new gaskets, hone, new rings, bearings, etc.
• 904 trans with stock stall
• Eddy RPM airgap
• Magnum front accessories including PS and A/C
• Cast iron exhaust manifolds
• Carb and ignition to be determined...

Stuff I'm keeping FOR NOW:

• 7 1/4 rear with highway gears
• Driveshaft
• Slant 6 k frame

About the trans. Debating between these two. One that is cheap, and close, and another that is a little bit more but comes with the torque convertor. Either way I'll rebuild the trans myself I think. I have plenty of time and winter is coming.

 

[skep419]

Thanks everyone for the hot debate.

The goal is streetable, as cheap as reasonable possible, as "easy" as reasonable possible, and with as much performance as we can eke out within those parameters.

It sounds like we have a plan:

• Stock motor, refreshed with new gaskets, hone, new rings, bearings, etc.
• 904 trans with stock stall
• Eddy RPM airgap
• Magnum front accessories including PS and A/C
• Cast iron exhaust manifolds
• Carb and ignition to be determined...

Stuff I'm keeping FOR NOW:

• 7 1/4 rear with highway gears
• Driveshaft
• Slant 6 k frame

About the trans. Debating between these two. One that is cheap, and close, and another that is a little bit more but comes with the torque convertor. Either way I'll rebuild the trans myself I think. I have plenty of time and winter is coming.

View attachment 1716478214
View attachment 1716478211

Fixed it "as cheap as reasonable possible"

 

[TT5.9mag]

Thanks everyone for the hot debate.

The goal is streetable, as cheap as reasonable possible, as "easy" as reasonable possible, and with as much performance as we can eke out within those parameters.

It sounds like we have a plan:

• Stock motor, refreshed with new gaskets, hone, new rings, bearings, etc.
• 904 trans with stock stall
• Eddy RPM airgap
• Magnum front accessories including PS and A/C
• Cast iron exhaust manifolds
• Carb and ignition to be determined...

Stuff I'm keeping FOR NOW:

• 7 1/4 rear with highway gears
• Driveshaft
• Slant 6 k frame

About the trans. Debating between these two. One that is cheap, and close, and another that is a little bit more but comes with the torque convertor. Either way I'll rebuild the trans myself I think. I have plenty of time and winter is coming.

View attachment 1716478214
View attachment 1716478211

I think it’s 70,71 (don’t quote me though) where the 904 got part throttle kickdown. I’d look for a trans that has it already. It’s not a deal breaker because you can add it, but it is another cost.

 

[HankRearden]

I've driven a bodies since 1992. I've had 225 318 2v,318 4v,la 360 4v,magnum 5.9 4v and 440 4v.
A junkyard fresh magnum and Chinese intake 5.9 is the absolute best bang for the buck.
Bone stock everything except Chinese intake and an old set of spitfire headers.
Best part is my wife and kid can easily drive it.
I guess what I'm trying to say is don't worry about hopping it up until you make it run.
You make like it stock if all you want is a fun cruiser.

 

[ScampNYC]

Fixed it "as cheap as reasonable possible"

Why no hone, bearings, rings? That stuff isn't that expensive...

 

[HankRearden]

Why no hone, bearings, rings? That stuff isn't that expensive...

You do whatever makes you happy and confident you aren't going to break down

But my experience is I've pulled three magnums down. None were worth honing or new rings.
One needed bearings.
All needed valve seals

The one in my 96 ram has 298000 miles. It needs valve seals badly but it still runs OK,has good oil pressure and pulls my car trailer.
But I don't have to drive in NYC traffic so I understand if some improvements bring peace of mind.

 

[273]

Did you read my post?
Did you understand it?
Lemmee help you.
Listen; I'm trying to be nice here;


Thus OP, as a laid back streeter, on any particular day, is almost never gunna hit the PowerPeak more than once and only on the way to getting up to hiway speed....... and when he does, the Torqueflite will drag the rpm down to 59%, and it's game-over.
Therefore,
my thought is;
Why sacrifice power where you need it/want it, say from take-off to 35mph,
to get that top-end power, where you hardly ever go?
*********************

Why people keep correcting you, as you can plainly see in the 2 dyno graphs provided plus the 1,000's of others out there, a mild cam made power practically throughout the whole powerband not just above 5,0000 rpms which the OP might find useful the extra under 5,000 rpms power and the odd time above 5,000 rpms if he chooses to go that way. Everyone is allowed an opinion but spreading faulty facts isn't opinion it's being manipulative.

 

[ScampNYC]

Ok folks, I am about done with the engine tear down.

My plan is to send the block and heads to the machine shop. Tell me if I have this right:

Block:

• Hot tank
• Clean up head surface
• Light hone on bores
• Replace cam bearings. What cam bearings should I get?

Heads:

• Hot tank
• Magnaflux for cracks
• If no cracks:
• Resurface. What should I do here?
  
  • A. Just a light pass to clean up/flatten the deck
  • B. Mill some meat off the heads to raise CR?
• Valve job
• Should I have them install new springs? Or should I just do that at home?

Random:

• What main bearings should I order?
• What rod bearings should I order?
• I've done an engine build before (a 440) and did the rings, main, and rod bearings at home, but should I just have the machine shop do it?
• Anything else I should remember or consider before the machine shop trip? Like, should I bring him freeze plugs, galley plugs, etc?

 

[junkyardhero]

Ok folks, I am about done with the engine tear down.

My plan is to send the block and heads to the machine shop. Tell me if I have this right:

Block:

• Hot tank
• Clean up head surface
• Light hone on bores
• Replace cam bearings. What cam bearings should I get?

looks good. clevite, sealed power, dura bond, mahle are all good choices.

Heads:

• Hot tank
• Magnaflux for cracks
• If no cracks:
  • A. Just a light pass to clean up/flatten the deck
  • B. Mill some meat off the heads to raise CR?
• Valve job
• Should I have them install new springs? Or should I just do that at home?

bueno, bueno. don't take any more than you need to get the surface true & clean. if you have the springs, you can have them install them, it's not gonna be much more $. the down side to doing it at home is that you need a spring compressor to do so.

so, pay or rent the tool vs. paying them is kind of wash. the benefit to doing it at home is that you can lap in the valves yourself which could save you some $

Random:

• What main bearings should I order?
• What rod bearings should I order?
• I've done an engine build before (a 440) and did the rings, main, and rod bearings at home, but should I just have the machine shop do it?
• Anything else I should remember or consider before the machine shop trip? Like, should I bring him freeze plugs, galley plugs, etc?

bearings, king if you can get them. otherwise same as above.

i like to let the shop do the freeze plugs and galley plugs, sometimes i'll have them install the cam because it's there. but i always set up the timing components and degree it myself.

on them assembling the bottom end, i guess it just comes down to time and money. if you have the money and not the time or think that your time is better spent elsewhere, then by all means. but if you're trying to bring it in on the cheap or that money could go to other go fast parts, then knocking it out at home is the jam. some people take a specific sense of accomplishment in assembling the whole thing themselves though, so there's that aspect too.

 

[remytherat]

Clean up head surface

Likely not necessary

What cam bearings should I get?

Standard stock replacement, not super critical. I used sealed power

Resurface. What should I do here?

likely not necessary

Should I have them install new springs?

Yes they will do it 20x faster than you ever could

• What main bearings should I order?
• What rod bearings should I order?

Standard stock replacement. King is what I used. Measure with plasti gauge. ez peesy

Anything else I should remember or consider

Heads are pretty likely to be cracked. Not a death sentence. Ton of info on here about that. Fingers crossed.

 

[michiganpat]

did you happen to measure how far down in the hole the pistons are? don't need to resurface unless you want to cut some to gain compression.

heads, even if they are cracked between the seats are probably fine if water tight.

might want them to trim the valve guides a skoash, can't remember how much lift you can get into before you risk the retainers/keepers hitting the guides stock. under .520 lift you're OK stock, IIRC.

I'd get springs and have them install/set the closed height if you don't already own a valve spring compressor.

Also, talk to the machine shop, they might have a distributor and be able to get the bearings and such for a comparable price as summit/rockauto/etc

 

[nckennyb]

I have a 360 magnum in a 1974 Duster. I used a 318 manifold on the driver's side and the manifold from a 1999 Dodge pickup in the passenger side. I hogged out the 318 manifold to match the ports and made the outlet as big as possible without weakening it too much. I did have to grind the head a little bit in the area near the rear head bolt for clearance with the 318 manifold. I have the Eddy Air Gap which works fine with the accessory drive from the 1999 truck. Mine is a factory air car so I'm using the A/C compressor and all from the truck. I didn't research enough prior to and used the truck PS bracket so I had to move my battery to the other side of the car like a Ford. It has plenty of power through those exhaust manifolds. Exhaust pipe is a pain in the tail with that tight turn on the driver's side though coming off the 318 manifold. I cut a bunch of slices of a 2 1/4" pipe and welded them together to make a tight elbow instead of making an elbow that's half crushed to death using a pipe bender.

 

[ScampNYC]

I have a 360 magnum in a 1974 Duster. I used a 318 manifold on the driver's side and the manifold from a 1999 Dodge pickup in the passenger side. I hogged out the 318 manifold to match the ports and made the outlet as big as possible without weakening it too much. I did have to grind the head a little bit in the area near the rear head bolt for clearance with the 318 manifold. I have the Eddy Air Gap which works fine with the accessory drive from the 1999 truck. Mine is a factory air car so I'm using the A/C compressor and all from the truck. I didn't research enough prior to and used the truck PS bracket so I had to move my battery to the other side of the car like a Ford. I has plenty of power through those exhaust manifolds. Exhaust pipe is a pain in the tail with that tight turn on the driver's side though coming off the 318 manifold. I cut a bunch of slices of a 2 1/4" pipe and welded them together to make a tight elbow instead of making an elbow that's half crushed to death using a pipe bender.

Woah nice, this is basically exactly what I'm doing!

Thanks for the input, all. I gues I get my springs together before bringing the heads in. Is this the spring kit I should get? Hughes 1199

 

[ScampNYC]

I have a 360 magnum in a 1974 Duster. I used a 318 manifold on the driver's side and the manifold from a 1999 Dodge pickup in the passenger side. I hogged out the 318 manifold to match the ports and made the outlet as big as possible without weakening it too much. I did have to grind the head a little bit in the area near the rear head bolt for clearance with the 318 manifold. I have the Eddy Air Gap which works fine with the accessory drive from the 1999 truck. Mine is a factory air car so I'm using the A/C compressor and all from the truck. I didn't research enough prior to and used the truck PS bracket so I had to move my battery to the other side of the car like a Ford. I has plenty of power through those exhaust manifolds. Exhaust pipe is a pain in the tail with that tight turn on the driver's side though coming off the 318 manifold. I cut a bunch of slices of a 2 1/4" pipe and welded them together to make a tight elbow instead of making an elbow that's half crushed to death using a pipe bender.

For the driver's side manifold, did you have to use an A-body manifold, or did you use a B or E body 318 manifold? thanks

There are some E and B body 318 manifolds near me for cheap, but wondering if they will work.

 

[JDMopar]

The B&E drivers side manifold won't work in an A body. Where the exit flange is wants to occupy the same space as the steering column/shaft. The correct A body manifold for the drivers side pop up at a reasonable price every now and then. B&E passenger side manifolds work fine in an A body, if you can buy onesie's. About every body style passenger side manifold dumps in the middle.

Edit...I meant to add that you should check with member @Capt46 He is in your area and may have or know of some manifolds.

 

[junkyardhero]

Woah nice, this is basically exactly what I'm doing!

Thanks for the input, all. I gues I get my springs together before bringing the heads in. Is this the spring kit I should get? Hughes 1199

yeah man, that's the juice you need to bring the smoothie together.

 

[Jarlaxle]

First: I haven't read the whole thread yet because I'm on my way to do laundry. (Yes, I'd rather be reading this site.) This might be duplicated, but I think I can help, because I HAVE a 360 Magnum in my Duster.

Hey guys, I had another thread called "What to Do with My Scamp" in which I described how I have a slant- six equipped 71 Scamp with oil pressure problems.

View attachment 1716477104


At the end of that thread, I decided to pick up a 5.9 Magnum to replace the worn slant six.


View attachment 1716477105


In this thread, I want to chronicle my build and ask some questions along the way.

My goals with this build and swap is to do it as cheap as reasonably possible. I also want to have the engine make decent power, but have great street manners. I have done the hot rod thing, I've had a 440 4 speed, multiple cars with lumpy cam and headers, and this time I want to make something that has good torque but is fairly civilize and super reliable.

Very easy. And cool van!

Actually, what I really want is for this Scamp to be a dependable, comfortable daily driver.

I'd like:
- Around 300 hp
- Air conditioning
- Power steering
- Cast iron manifolds! Yes, that's right.
- Hoping to reuse my rotating assembly (crank, cam, piston, rods, roller lifters)

Not especially difficult, as long as you don't mean a cast iron intake. Mine was 300RWHP and over 400lb-ft, with stock-rebuilt long block, mild cam, Doug's headers, Air Gap intake, 650 AVS. Magnum manifolds flow pretty well, though fitting with power steering (or column shifter) might be an issue.

Right now my spend is:
$375 for the motor.

Tonight I started tearing it apart. It looks a little sludgey in there, more than I was expecting. Hopefully the bores look okay. The motor had 101k miles, according to the junkyard.

View attachment 1716477106


As I start pricing out all the needed parts, I am really shocked to find that the motor itself is pretty much going to be the cheapest part of the build! Crazy that an aluminum intake is now $500. Last time I did this, they were $300.

EBay saved search under the PN. Also, places like Racingjunk, the return/scratch & dent stuff at Summit, swap meets, and Carlisle. There's a Chinese Air Gap clone on eBay for $152.

Is this an A/C car? If not: Coldmaster. (Search that name here, there are several threads.) If so...also Coldmaster, they'll happily sell individual components.