Is a 4.7 swap worth the hastle

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User0511

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My neighbor's kid just bent a 2WD dakota around a pole. It was a 38K motor. It runs and drives - just tough to stay straight. I wonder if it is even worth to try to put it in something- old?
 
What year is the engine? I have had three of them. My 2002 Jeep has a 4.7-HO, I had a 2005 Durango with a 4.7 and my 2008 Aspen has a 4.7 "Semi-Hemi", as it was called internally when they changed the heads, spiked the HP. All of my 4.7s were great engines, but the Aspen really lights them up.

I've thought about swapping a High Output 5.9 into my LeBaron.
 
I saw on another site a guy put a Pentastar V6 in an A body and it mates to a 904.

I had a HMMMMMM moment.
You get 300hp which is about what you're getting from a small block,
no under hood room issues, lighter,
lots of parts,
take it to any Mopar dealer,
runs no problem on todays crap gas and good gas mileage.
Figure out how to mate a 8 speed to it.

Been thinking it would be a nice fit in an M.
 
I've heard not so great things about the 4.7s warpin heads
I know when I worked at the dealer quite a few durangos and rams came because of overheating/coolant leaks
 
Nov 2004 is the manufacture date on the door. It is a hi output according to the aircleaner. The thermostat is on the bottom - not out the top. What is up with that bassakwards design? I know the motor was a strong one. The kid was a want to be drifterand would lay down a 40 foot patch easily. Not enough front tire to hold it straight and BAM. He got it with the low miles from an old timer who bought it and drove it between oil changes. I hear they can go long, but I also hear they go down hard without warning.
 
Dr Lebaron said:
I saw on another site a guy put a Pentastar V6 in an A body and it mates to a 904.

I had a HMMMMMM moment.
You get 300hp which is about what you're getting from a small block,
no under hood room issues, lighter,
lots of parts,
take it to any Mopar dealer,
runs no problem on todays crap gas and good gas mileage.
Figure out how to mate a 8 speed to it.

Been thinking it would be a nice fit in an M.
Click to expand...
I like everything about what you said, but a V6 will never sounds as good as a V8.
 
LSM360 said:
I like everything about what you said, but a V6 will never sounds as good as a V8.
Click to expand...


I've thought about it a lot too.....
It would be a very cool swap in say a Gran Fury that came with a six originally.
Be a hell of a sleeper too....
 
As appealing as the Pentastar V6 looks at first glance with it's impressive HP and torque numbers, to get those numbers it's by necessity a somewhat peaky engine. This is why we're seeing 5-, 6-, even 8-speed automatic transmissions these days--it's the only way to keep the engine near the "sweet spot" of its narrow power range. Hooked to a 904, I would expect it to be relatively laggy when compared to its intended transmission. I wouldn't think it would be nearly as fuel efficient either. It's a pretty common issue with multivalve engines. No one ever called a Neon a torque monster, particularly with the 3-speed auto. There's just too much port volume to make a broad, flat torque curve as you naturally get with a 2-valve engine like the Magnum V6 or any one of the classic V8 choices. Of course that could be overcome with forced induction, which is why a fairly-small engine like Porsche's flat six in the 911 is an absolute brute, even down low.

If I were considering a naturally-aspirated six cylinder, I'd probably look at either the Slant Six or the 3.9L Magnum. Both are pretty torquey and work well with the low gear counts to which we're accustomed in these cars. Either one is a much simpler swap, too. There are plenty of speed parts out there for both, though an aftermarket 3.9L intake's getting tougher to find--camshafts aren't bad; you can always have yours reground in a performance profile based on a V8 pattern.
 
Dunno.....but we have the Pentastar in our 11 Charger. It totally impressed me. 292hp and still gets between 25 and 30 mpg. I'm not really a six fan but.....
 
80 Aspen RT said:
Dunno.....but we have the Pentastar in our 11 Charger. It totally impressed me. 292hp and still gets between 25 and 30 mpg. I'm not really a six fan but.....
Click to expand...
With someone driving a 110hp /6 or the 90hp California 1bbl /6, 292Hp sounds appealing without added weight.

Gonna cost money to get 292hp out of an average small block w/o going to a Gen3 Hemi.
 
Gonna cost a lot less money to get 300HP out of a 318 than it is to put in a Pentastar V6. A lot less work, too.
 
I agree; the new V6 in the Charger Police car is actually quite impressive. Really is the torque number that you gotta look for, IMO. The one thing the V6 can never match though is the sound of the V8. I have heard plenty of Police Impale-ya's and new Phord Interceptors, as well as Charger V6's at WOT, and they still sound like a V6. Even the twin turbo Phords sound lame. They have impressive acceleration but sound like a turd IMO.

As far as the 4.7 being worth it; If I were going to go through the work of swapping in a late model engine, I'd do it "right" the first time. I'd swap in a 5.9 FI Magnum (if budget conscious), or a crate engine 360. I think the fabrication and parts are going to be the killer as far as costs and work, so might as well spend a little more and get some serious power now. Nothing wrong with the 4.7, just saying go for the gusto.
 
LSM360 said:
I agree; the new V6 in the Charger Police car is actually quite impressive. Really is the torque number that you gotta look for, IMO. The one thing the V6 can never match though is the sound of the V8. I have heard plenty of Police Impale-ya's and new Phord Interceptors, as well as Charger V6's at WOT, and they still sound like a V6. Even the twin turbo Phords sound lame. They have impressive acceleration but sound like a turd IMO.

As far as the 4.7 being worth it; If I were going to go through the work of swapping in a late model engine, I'd do it "right" the first time. I'd swap in a 5.9 FI Magnum (if budget conscious), or a crate engine 360. I think the fabrication and parts are going to be the killer as far as costs and work, so might as well spend a little more and get some serious power now. Nothing wrong with the 4.7, just saying go for the gusto.
Click to expand...


I agree....best swap I've heard of to date is a Magnum 360 from a boneyard Dak or something similar....less hassle and money and good power.
 
Btw, the only two 6 cylinder engines I have ever really liked are the Slanty of course, and in second place the old Jeep 4.0
 
IMO dont bother. Get a used 318/360 Mag, dump the OBD-1 or OBD-2 SD crap, slap a carbed intake and carb on it.

Now this (minus the SC http://www.youtube.com/watch?v=TqD195hClWk ) would be my chioce if I were to get froggy injecting a older Mopar.

1974 Cuda, Barracuda, Mopar
S-trim Vortech Supercharged 408 Cuda.
Chrysler 5.9 Magnum small block stroked to 408.
360 Mopar with Ford EFI, EEC-IV mass air computer.
Fuel Injected Mopar, Cuda, Barracuda, Dyno

The most difficult part would be to get the ford distributor reworked to fit a Mopar SB. Obviously it can be done. Hughes already makes an FI air gap or you can go with Ma Mopar M1. The ford EEC IV is mass air and can take heavy engine mods than can the Mopar Speed Density system. It is easy to work with.

Here's the original thread for his conversion
http://www.cuda-challenger.com/cc/index.php?topic=7247.60
 
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NoCar340 said:
Gonna cost a lot less money to get 300HP out of a 318 than it is to put in a Pentastar V6. A lot less work, too.
Click to expand...

Yea, at the free store.
A stock 80's 318 can't barely get 150 HP.

I just saw a Pentastar set up for $1600.
Bolt it to a 904.

So who doubles 318 HP for $1600 Canadian dollars?
A good carb runs $500 alone.
 
Dr Lebaron said:
Yea, at the free store.
A stock 80's 318 can't barely get 150 HP.

I just saw a Pentastar set up for $1600.
Bolt it to a 904.

So who doubles 318 HP for $1600 Canadian dollars?
A good carb runs $500 alone.
Click to expand...

Don't forget the fab work to mount it.
If you're paying someone else to do the work prepare to chunk a lot of coin into that.
 
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