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WipLash
R/T
2/26/2004
13:27:18
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 Subject: RE: 4.7L Under Powered!?
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Justi,
That's where it really gets embarrasing. The 4.7L w/auto hadd 3.55's and a .71 OD for a final ratio of 2.52:1.
My 5.2L auto also had 3.55's but it's OD was .69 for a final ratio of 2.49:1.
Both trucks had basically the same diameter tire. My 93 & 94 had 28.88" diameter tires and my 2002 4.7L had 29" diameter tires.
So both trucks were basically identicle as far as the gear ratio and tire size.
Bottom line is the 4.7L doesn't have enough low end torque. There's only 2 ways to make low-end torque. Either with forced air induction or CUBIC INCHES and the 4.7L has neither.
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Kowalski
Dodge Dakota
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2/26/2004
16:16:49
|  RE: 4.7L Under Powered!?
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That's funny, adding HO cams adds significant low end torque to a 4.7; not using either way you claim are the only two ways...
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WipLash
R/T
2/26/2004
23:57:50
| RE: 4.7L Under Powered!?
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I'm sure the HO cams have more torque across the mid and upper RPM's. That's why they come on Grand Cherokees. They don't need as much low-end torque. I'm talking torque below 2200 RPM. That is where you will be most of the time pulling a trailer. The 5.2L has more torque than the 4.7L below the 2500 mark. The 4.7L is better at passing cars empty. The 5.2L is better at pulling a trailer.
If it was so damn good I would have kept it. It had the typical "I'm a little engine and I think I'm a big engine" charactor.
I did leave out one modification that adds a significant amount of torque and that is increasing the compression ratio. It's real easy to raise the comp-ratio on a 5.2/5.9L.
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GraphiteDak
GenIII
2/27/2004
00:41:31
| RE: 4.7L Under Powered!?
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The OD ratio on my 3.55's is pretty tall. Stays somewhere around 1500 or so RPM's at highway speed.
On the flat my loaded 4X4 QC stays in 5th gear most of the time. It occasionally drops to 4th. The cruise control seems to overshoot like I said before. But I think these engines have lots of DOWN low power.
My bro in law has a 2000 RC RAM 1500 with a 5.2
He drove my truck one night and said he LIKED the way my truck had that INSTANT power out of the hole.
We have ran a few times unloaded, we are almost a dead match. Mine seems to have more power TOWING on the hills. His is a RC 2WD, no power nothing and I think 3.92 gears after his gear swap and 31 10.50 tires.
Mine is a Quad Cab 4X4 with power everything. I am pretty sure my Dak out weighs his RAM in this case.
After my cam swap he'll be back staring at my tail lights.
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WipLash
R/T
2/27/2004
13:50:05
| RE: 4.7L Under Powered!?
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I admit the 4.7L pulls better across the total usable RPM range. With the 45re's lower 1st gear ratio you get better torque multiplication than you do with the 518's. The transmission plays a big role in the 4.7's performance. Had the 5.9 and the 5.2L had the transmission the 4.7L has there would be no contest. It is also the reason the 4.7L can run pretty much even with an R/T in the 1/4 mile. The story Mopar Now did between the R/T and the 4.7L explained it best. The lower gear ratio of the 45re's 1st and 2nd gears made the final ratio for the 4.7L over 10:1 in first. The R/T only has like 9:1 final gear ratio in first gear. That's a big difference. It allows the 4.7L to get up in it's torque band quickly, but once it is in OD everything is equal as far as gearing is concerned and the 4.7L has to downshift in order to accelerate or maintain speed going up small inclines where the 5.2L and the 5.9L can do it without downshifting. Since I do most of my trailer pulling on the interstate and highways the 5.2/5.9L suits me best. If I had to pull a trailer in town where there was a lot of stopping and going then I would choose the 4.7L.
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Kowalski
Dodge Dakota
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2/27/2004
15:17:39
| RE: 4.7L Under Powered!?
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Wiplash - I'm talking about torque below 2200 too, so no need to try to correct me. In fact, the HO cams increase torque everywhere. Another mod that will increase torque everywhere is a little more ignition advance - again, not one of the 2 ways you claimed are the only ways to increase torque.
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318Magnum
Dodge Dakota
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2/27/2004
17:18:13
| RE: 4.7L Under Powered!?
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The 4.7's will not amount near up to the 318 work horse. Did I say the 4.7's where junk..NO, its just that they will not hold as big of name as the 318 did.
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Trukguy
Dodge Dakota
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2/27/2004
18:11:39
| RE: 4.7L Under Powered!?
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I really hope you are right. Hopefully DCX won't try and use the same design for the next 30 years like they did with the 318.
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WipLash
R/T
2/27/2004
18:49:17
| RE: 4.7L Under Powered!?
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Kowalski,
I'm talking significant gains in torque. Raising the ignition timing will only increase the torque if there isn't enough timing to begin with. When you are towing you are in a low vacuum state half the time due to the throttle blades being open wider. Too much ignition timing pulling a heavy load will cause detonation and that will REDUCE your torque. You’re flirting with disaster on the 4.7L when you increase the ignition timing and drive it under heavy loads. Aluminum headed engines are very prone to blowing head gaskets. When you advance the timing you triple the odds of having detonation. Detonation alone will blow a head gasket. Throw in the fact that you have weaker Al-heads that flex and break seal much easier than cast irons with the increased likelihood that you are going to detonate with the timing jacked up pulling a load and you have the perfect recipe for a blown head gasket. There have already been threads on this forum concerning this. The 5.2/5.9L can safely handle more ignition timing without the risk of blowing head gaskets.
Bottom line, all the modifications you keep bringing up on the 4.7L to increase the torque and HP also work on the 5.2L. Not only do they work, but they work for half the amount of money. Therefore, quit throwing in things like HO-CAMS, Intakes, TB's, PCM's, relocating this or that because all of these modifications can be done to the 5.2L easier and cheaper than they can be done to the 4.7L. Then there's the Cubic Inch factor. Take any 2 engines and make the same modifications to both engines. The engine with the most cubic inches will see the most gain in HP. So, if you took the 230hp 5.2L and the 230hp 4.7L and made relatively equal changes to both engines, the 5.2L would have more HP and Torque when finished. Size really does matter. No matter what your wife may have told you.J/K
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01Motorsport
Dodge Dakota
JOIN HERE
2/28/2004
08:32:27
| RE: 4.7L Under Powered!?
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The auto manufacturers have used extra valves and /or camshafts to compensate for reduction in cubic inches. Sure there will be variations in the torque curve between a 4.7 and 5.2, but I believe Chrysler did an admirable job with the SOHC compensating for .5 liter capacity. I cannot, however, appreciate your comparisons of automatic trans. vehicles, because the 3:92 5-speed manual in my RC suits the 4.7 so perfectly in all conditions.
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Kowalski
Dodge Dakota
JOIN HERE
2/28/2004
09:33:14
|  RE: 4.7L Under Powered!?
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I'm talking about significant gains too. Cam change to HO for 4.7 is probably half the $ of a cam change for a 5.2, so you have that backwards. Higher octane fuel for higher load aplication will take care of detonation, and with aluminum heads, the 4.7 is less prone to detonation than the 5.2. Im aware that cubic inches are the easiest way to greater torque, nothing new there. It might be little, but its cute. The 4.7, that is.
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WipLash
R/T
2/28/2004
11:23:49
| RE: 4.7L Under Powered!?
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01Motor,
I'm confused about your comment on the transmissions. I was complimenting the new 45re that's behind the 4.7L. I thought it was the best attribute on the truck and the one thing that made it better than my R/T (Significantly Better). The 46 trans SUCKS. This has to be the worst shifting automatic I have ever owned. I was talking about automatics. I'm sure any truck would run better with the 5spd. For one, the only time it would downshift is when you decide to.
Kowalski, half price for the 4.7L cams? The regrinds for the 4.7L are like $20.00 cheaper than the regrind on a 5.2L. If you buy NEW camshafts (NOT REGRINDS) the 5.2L is $90.00 cheaper than the 4.7L. What about headers? The last I checked the average price for 4.7L headers were $150.00 higher than the 5.2/5.9L. Then there's the PCM. If you can even get one for the 4.7L it's $100.00 higher than the 5.2/5.9L. There were no flashes or PCM's available for my 2002 4.7. What about heads and intakes? There are some available for the 5.2/5.9 engine. Most of the performance parts for the 4.7L have to be made from scratch.
Then there's TB porting. For whatever reason, I can get my 2bbl T/B ported $30.00 cheaper than I could my 1bbl TB on my 4.7L. I never understood that one. You would think that boring out 1 bore would be cheaper than boring out 2.
The list goes on and on. You can buy parts on-line all day for the 5.2L for less than the 4.7L. The only thing on the 4.7L that's cheaper is the lifters and pushrods and that's because they don't have any. I've never had to replace a roller lifter. I know they are expsensive. That is one expense I will eventually have to deal with that the OHC 4.7L owner never will.
Now, lets compare the prices of timing chains......... HA!! Gotch Ya!!
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Jeeper
Dodge Dakota
JOIN HERE
2/29/2004
02:23:33
| RE: 4.7L Under Powered!?
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WOW, lets all talk about how great my engine is and how lousy yours is. This discussion goes nowhere and has been replayed ... lets see... 85,000 times over the last 5 years.
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WipLash
R/T
2/29/2004
10:05:52
| RE: 4.7L Under Powered!?
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Lets see....
The word Jeep was originally Spanish. In Spanish the letter "J" is pronounced like an "H". The Spaniards used the word Jeep (Heap) to describe a pile of Sh!T. Now you know the rest of the story.....
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Kowalski
Dodge Dakota
JOIN HERE
2/29/2004
10:37:32
| RE: 4.7L Under Powered!?
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You're just a fountain of misinformation, aren't you ? The word jeep came from military use, from GP, General Purpose vehicle.
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TexasTodd
Dodge Dakota
JOIN HERE
2/29/2004
17:55:56
| RE: 4.7L Under Powered!?
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WipLash,
NO pissing war here, OK?
My HO cams, were $112, SHIPPED, FOR BOTH CAMS!!
It was like $53, per cam, from a Dodge/Jeep dealer in Rhode Island. New Chrysler Products. That was in 2001, I know they've gone up some since then.
It seems you've owned both engines, both autos, and have a good comparison.
01, QC, 2wd, SLT, trailer towing, tire and handling, Infinity sound, overhead puter added, rear slider and slider on my cab high Leer cap, fender flares,
01, 4.7, 5spd(the one you have to shift), LSd, 3.55's (for now),HO cams, and 02 HO intake, NO stinkin belt clutch/fan, ported 68mm TB, IAT adjuster, (off usually), Homebrew 'true CAI' with K&N, 3923's, Mobil 1, heater core water bypass,
I understand you're comparing the 5.2, and 4.7 with autos, I wonder what someones' who owned/drove both comparison would be with the manual tranny.
Cause, I really love my 5spd, even with the 3.55's towing my sailboat, etc.
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WipLash
R/T
2/29/2004
19:32:29
| RE: 4.7L Under Powered!?
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TexasTodd,
We can all go to the flea market and find bargains if we look hard enough. I'm comparing retail prices, which is what the average Joe is going to pay at the aftermarket parts warehouse. Hell, there are 5 cams being bid on right now on Ebay for $10.00 for the 5.2/5.9 engine? I doubt that they will sell for that price but there is only 15 hrs left on the bidding. They won't sell for much more that $10.00.
It's time for a reality check here. The 4.7l will never be as cheap as the 5.2L to build. There is no argument there. For the same reason the 5.2L Dodge will never be cheaper than a 5.7L Chevy the 4.7L will never be cheaper than the 5.2L. Start lining up all the parts for a rebuild or performance upgrade and the 5.2L will be 25-50% cheaper to do than the 4.7L and the HP gains for the 5.2L will be slightly better than the 4.7L just because it is bigger. That's just the simple facts of life.
Bottom line is the displacement. Give both engines 100% volumetric efficiency (blower/Super charger) and the 5.2L will be making about 10% more HP because it's 10% larger.
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Trukguy
Dodge Dakota
JOIN HERE
2/29/2004
20:53:28
| RE: 4.7L Under Powered!?
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Whiplash should change his name to Longwinded.
He's absolutely full of misinformation about so many things that it would probably take a thread that's already this long to explain all of the errors to him. He's just another R/T guy that's butt-hurt because somebody in a 4.7 stomped his truck in some sort of speed contest.
Here's a little bit of advice for you Ray. Get over it. Stop trying to be some sort of 5.2/5.9 evangalist. If guys already have a 4.7 they don't need to hear your lies and incorrect assumptions. They are quite capable of making up their own mind without somebody like you. You might be some sort of an engineer and think you're a fountain of knowledge, but you don't know squat about the 4.7 engine or the areas it's design is superior to your 5.9. We're tired of hearing your crap. You don't have a clue and should stick to arguing about which spark plug or thermostat to run in your 5.9. Maybe a thread about your leaking plenum gasket or troubles getting the fuel sync right would be better?
Bottom line. Shut the hell up.
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Hey
Dodge Dakota
JOIN HERE
2/29/2004
21:20:21
| RE: 4.7L Under Powered!?
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Where did Marine Tanker go? He posted the original question but never came back. Just look at what he started with his innocent question!
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WipLash
R/T
2/29/2004
21:57:21
| RE: 4.7L Under Powered!?
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I got news for you. As long as this thread is running I will be on it.
I obviously know more about the 4.7L than you do. I owned one for 2 years. And this is my 4th OHC engined automobile.
I can also tell which direction this is heading in. A good engineer could design the V8 so that the cylinder head could interchange with the 4cyl. How much would you be willing to bet that in the next 10 years there will be a 4cyl in the Mercedes/Dodge line-up that shares the cylinder head of the V8? Just think how much money they would save if all the 4cyl and 8 cyl engines shared the same head. That brings us to the V10. How hard would it be then to have a 5cyl engine that shared the head of the v10? Or possibly make a 3cyl that shared the head with the V6.
Now for the punch line:
They will be sharing parts between the 4cyl and the 8cyl in the near future. To do this they had to make the 8cyl an OHC. Do the math. 4.7L/2=2.4L. That's the displacement in the SRT4.
Now, try making a 4cyl with the cam in the block. It would require extensive retooling and a very elaborate mold/casting to get the cam off to one side of the block. Therefore, in order for the V8 and the 4cyl to share heads they had to make the V8 an OHC. They will convince the public that this move was for improved efficiency and more HP instead of reducing cost. Just like they convinced the public FWD was safer and better than RWD.
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