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Discussion Starter #1
So i was just curious how much it would cost to semi build a good reliable 4.7 engine and what you guys would recommend to do(heads,bore etc)? im just curious so i could get an idea of what i am looking at

Thanks in advance
 

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just the stock motor is reliable. What are you looking to build a motor for?
exactly? if you don't plan on going forced induction or something with huge demand then they are good stock. if you want some nice n/a bolt on's then look into getting krc cams and heads. after the price you pay for them you won't want to spend more on the bottom end heh.
 

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www.AIRRAM.com
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We can help you with just about anything you need... but as mentioned above you need to decide on exactly what you are expecting and what your performance goals are... this way we can help you make the best choices.

SPEED SAFE, AIR RAM
 

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Discussion Starter #5
i wanna build it so i can be able to supercharge or turbo it down the road and my engine has over 250,000 miles so i thought a rebuild will be in the future and if im rebuilding it might as well do some work. so i was just curious what to do prices and estimated power gains.
anything will help
thanks
 

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Depending on how radical you want to go with boost, you might want to get some pistons and rods from AirRam (he's got some of the best prices and is very helpful). The stock rods are good for maybe 400hp but I wouldnt trust them to much more. HO cams and SCT are a good start. Then you sill have the tuning ability of SCT to take advantage of Forced Induction. (I hope to get SCT this year cause I got a Paxton 4.7 at only 6 PSI and I want to bump that up LOL)
 

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Depending on how radical you want to go with boost, you might want to get some pistons and rods from AirRam (he's got some of the best prices and is very helpful). The stock rods are good for maybe 400hp but I wouldnt trust them to much more. HO cams and SCT are a good start. Then you sill have the tuning ability of SCT to take advantage of Forced Induction. (I hope to get SCT this year cause I got a Paxton 4.7 at only 6 PSI and I want to bump that up LOL)
I personaly do not feel the stock rods are safe at the 400HP mark for any extended period of time. They are super thin and I was shocked how thin they where after picking up the pieces of two rods in two different blocks... there is NOTHING impressive about the stock rods. If your planning on aftermarket pistons I HIGHLY recomend adding a good set of our SCAT rods to go with them.

Take your time and chose your Compression ratio wisly. If you plan on a low boost engine 8-10psi then you may want to consider a 10:1cr engine... If you plan to run 11-15 PSI then you may want to consider a 9:1cr engine.

Chose your boost level realisticly. 10psi on a 300HP engine is worth about 200RWHP... So 10psi could make up to 500RWHP... So you dont need tons of boost to make HP. And a higher initial CR will make more low end torque for low RPM fuel economey and better towing at lower RPMS.

If you have any questions please feel free to contact me.

SPEED SAFE, AIR RAM
 

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Discussion Starter #8
ya i was thinking about 7-10 pounds and i am gonna be pulling the motor this fall when i have all the money saved up to do it. if i wanted to build a motor that can handle 10 pounds of boost how much money am i looking at? and ya i have been looking at all kinds of stuff on airram.com. i most likely will be buying most of my parts off of there
 

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I cannot remember exactly, but here is an approximation of my engine buildup.

HO Core: $1350
Crower billet rods: $1600
Ross 8.1:1 slugs: $900
Head/valve work: $2000
Cams: $500
Balance/machine shop: $300
Bearings, gaskets, etc: ?
ECU: $3000-ish on Ebay
I would not bore.

Most important thing to bring this together or a stock engine with boost:
Tune, tune, and tune.

Do yourself a favor and pickup a copy of Corky Bell's "Maximum Boost".
 

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www.AIRRAM.com
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I cannot remember exactly, but here is an approximation of my engine buildup.

HO Core: $1350
Crower billet rods: $1600
Ross 8.1:1 slugs: $900
Head/valve work: $2000
Cams: $500
Balance/machine shop: $300
Bearings, gaskets, etc: ?
ECU: $3000-ish on Ebay
I would not bore.

Most important thing to bring this together or a stock engine with boost:
Tune, tune, and tune.

Do yourself a favor and pickup a copy of Corky Bell's "Maximum Boost".
You will be please to know you could do it for more then $1000.00 less then that through AIRRAM.com ... Where where did you go for your parts... I was not aware of anyone other then us who carried bolt on Rods/Piston combos and I from what I know, we are the only place that offers Rods that are sized for the factory crankshaft. There is one other place that sells rods, but there rods are not sized for the 4.7L crankshaft and do NOT fit without modifying the crank. With there rods you need to pay more and have your crank modified to fit there rods... One of those hind site un expected expenses that just add to the price of your build up. Our rods cost you less and are a direct fit to your 4.7L crankshaft.

Check out this link for our 4.7L SCAT H-BEAM RODS... ($675.00 ARP 8740 bolts) or ($765.00 ARP 2000 Bolts)

We also offer Ross Pistons starting at 804.00... click here for details.

So above you where looking at spending 2500 bucks on Rods & pistons alone... while through us you can get both the RODS (ARP200) & Pistons for $1569.00 ... thats nearly 1,000.00 saved right there alone... Our prices and parts can not be beat!

Also check out our ARP Head stud & Bed Plate stud kits.


Also, we where able to go .040 safely on our current 4.7L engine build up.

SPEED SAFE, AIR RAM
 

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Where where did you go for your parts...
I had Marty at KRC get the rods, pistons, and cams for me, three years ago. I'm sure Crower can make the rods again for anyone (they were custom billet). The rods are connected to the stock crank. I'd have to dig through my records, but I think the wrist pins are a standard Ford or Chevy size.

Note to the OP. I forgot I also used ARP head studs. IIRC, they were $250. I worked with ARP directly. They were able to modify an Acura head stud (shorten on the block side and use with two washers on the head side). I think there is another option available with AirRam.

For interested 4.7 people, I'll see if I can dig up some photos of the parts and post.
 

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Valve Springs:

I almost forgot about valve springs. Non-HO and HO stockers will float with exhaust backpressure, even with 7psi on a stock engine.

For my buildup, neither stocker would work with the cams (coil bind). So, I used Crane springs for a modular Ford. IIRC ~95# seat pressure. Those floated too with backpressure on the exhaust side. Then tried a Competition Cams valve spring with ~135# seat pressure. Did the trick. And yes, it as exhaust valve float, not intake valve float (no change in AFR during power dip).

Run 10--stock engine, 60-1 turbo (7psi), stock valve springs (70-80# seat pressure).
Runs 6 & 67--built engine, similar boost levels (~7psi) before and after fix.
Runs 26 & 77--built engine, similar boost levels (~10psi) before and after fix.

Couple of notes about the dyno. Inertia type, system wouldn't boost as early as it does on the street. The power band on the street starts around 3900rpm compared to around 4300 on the dyno chart. Also note how choked the 4.7 manifold is after 5800.
 

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I love my 3.9 and Jesus
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Valve Springs:

I almost forgot about valve springs. Non-HO and HO stockers will float with exhaust backpressure, even with 7psi on a stock engine.

For my buildup, neither stocker would work with the cams (coil bind). So, I used Crane springs for a modular Ford. IIRC ~95# seat pressure. Those floated too with backpressure on the exhaust side. Then tried a Competition Cams valve spring with ~135# seat pressure. Did the trick. And yes, it as exhaust valve float, not intake valve float (no change in AFR during power dip).

Run 10--stock engine, 60-1 turbo (7psi), stock valve springs (70-80# seat pressure).
Runs 6 & 67--built engine, similar boost levels (~7psi) before and after fix.
Runs 26 & 77--built engine, similar boost levels (~10psi) before and after fix.

Couple of notes about the dyno. Inertia type, system wouldn't boost as early as it does on the street. The power band on the street starts around 3900rpm compared to around 4300 on the dyno chart. Also note how choked the 4.7 manifold is after 5800.
NICE numbers!! What's your 1/4 mile info?
 

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nice setup! Just wondering, why did you go with an HO core vs building the normal stock motor? If I recall correctly the main difference is just the crank and heads but if you have head work done anyway does it really matter? Also do you think a cast crank would be good for 400 HP?

Do you have any pictures of the turbo setup?
 

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nice setup! Just wondering, why did you go with an HO core vs building the normal stock motor? If I recall correctly the main difference is just the crank and heads but if you have head work done anyway does it really matter? Also do you think a cast crank would be good for 400 HP?

Do you have any pictures of the turbo setup?
Went with an HO core for a few reasons: the forged crank, heads (I think the main difference is quench pad size), extra wire harness with knock sensors, and the ability to take my time building the thing while still driving the truck. It was a big project as I did the engine buildup, fuel system, EMS, T-56 conversion, and turbo upgrade at the same time so I wanted everything ready to go at once.

PS I don't think I have any recent pix. I'll try to post some later in the spring. The truck is on jackstands currently in the middle of a clutch disc R&R.
 

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I'd like to do a 4.7 build sometime in the future and I was wondering if there is an actual difference in the blocks? I can get a blown 4.7 for just about free but it's not the HO version. Could you swap in a forded crank anyways?
 

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I'd like to do a 4.7 build sometime in the future and I was wondering if there is an actual difference in the blocks? I can get a blown 4.7 for just about free but it's not the HO version. Could you swap in a forded crank anyways?
As far as I know the blocks are the same. I recall reading an article that stated they have the same casting number. Some of the early non-HO blocks may not have the knock sensor bosses tapped.

For swapping cranks, yes. But, you'll need to properly size the main bearings. The size is stamped on the crank sensor reluctor ring.
 

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You will be please to know you could do it for more then $1000.00 less then that through AIRRAM.com ... Where where did you go for your parts... I was not aware of anyone other then us who carried bolt on Rods/Piston combos and I from what I know, we are the only place that offers Rods that are sized for the factory crankshaft. There is one other place that sells rods, but there rods are not sized for the 4.7L crankshaft and do NOT fit without modifying the crank. With there rods you need to pay more and have your crank modified to fit there rods... One of those hind site un expected expenses that just add to the price of your build up. Our rods cost you less and are a direct fit to your 4.7L crankshaft.

Check out this link for our 4.7L SCAT H-BEAM RODS... ($675.00 ARP 8740 bolts) or ($765.00 ARP 2000 Bolts)

We also offer Ross Pistons starting at 804.00... click here for details.

So above you where looking at spending 2500 bucks on Rods & pistons alone... while through us you can get both the RODS (ARP200) & Pistons for $1569.00 ... thats nearly 1,000.00 saved right there alone... Our prices and parts can not be beat!

Also check out our ARP Head stud & Bed Plate stud kits.


Also, we where able to go .040 safely on our current 4.7L engine build up.

SPEED SAFE, AIR RAM
Old thread but damn the price for rods really went up! Bummer
 
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