Re: Difference in 5.7 or 6.4
[Re: Smoparmike]
#3013426
02/08/22 04:23 PM
02/08/22 04:23 PM
|
Joined: Jan 2005
Posts: 12,419 Kalispell Mt.
HotRodDave
I Live Here
|
I Live Here
Joined: Jan 2005
Posts: 12,419
Kalispell Mt.
|
The 6.4 tows better, more about the TQ than the HP, a 5.7 downshifts a lot without a trailer, my 6.4 (not exactly stock) pulls way better than a 5.7. I actually buy 5.7 trucks with bad engines and stick 6.4s in with a simple upgrade recipe that is much better than even a stock 6.4.
If your willing to build a truck up the best combo seems to me to use a 6.4 truck short block, 6.4 SRT8 injectors with 5.7 heads, intake cam... as the 5.7s make more TQ per CID than the 6.4. This also gives you more compression than a regular 6.4 truck and is a beast for towing, I currently have this exact combo in my 2011 4x4 4 door long bed and towed an identicle configuration truck on a heavy 20ft tilt-deck trailer and even going up a couple big mountain grades only un-locked the TQ converter and did not downshift. I got 11.5 MPG towing that truck. It pulls even better than an actual stock 6.4 truck and cost about 1/2 what one of those trucks would cost. The real 6.4 trucks use EGR witch I hate, the 5.7s don't have it.
I did one with a 6.4 SRT8 engine and it pulled even better but it liked to run much higher RPM also, this current one is much more satisfying when pulling.
I am not causing global warming, I am just trying to hold off a impending Ice Age!
|
|
|
Re: Difference in 5.7 or 6.4
[Re: HotRodDave]
#3013707
02/09/22 01:36 PM
02/09/22 01:36 PM
|
Joined: Mar 2010
Posts: 1,061 Atlanta, GA
mgoblue9798
super stock
|
super stock
Joined: Mar 2010
Posts: 1,061
Atlanta, GA
|
The 6.4 tows better, more about the TQ than the HP, a 5.7 downshifts a lot without a trailer, my 6.4 (not exactly stock) pulls way better than a 5.7. I actually buy 5.7 trucks with bad engines and stick 6.4s in with a simple upgrade recipe that is much better than even a stock 6.4.
If your willing to build a truck up the best combo seems to me to use a 6.4 truck short block, 6.4 SRT8 injectors with 5.7 heads, intake cam... as the 5.7s make more TQ per CID than the 6.4. This also gives you more compression than a regular 6.4 truck and is a beast for towing, I currently have this exact combo in my 2011 4x4 4 door long bed and towed an identicle configuration truck on a heavy 20ft tilt-deck trailer and even going up a couple big mountain grades only un-locked the TQ converter and did not downshift. I got 11.5 MPG towing that truck. It pulls even better than an actual stock 6.4 truck and cost about 1/2 what one of those trucks would cost. The real 6.4 trucks use EGR witch I hate, the 5.7s don't have it.
I did one with a 6.4 SRT8 engine and it pulled even better but it liked to run much higher RPM also, this current one is much more satisfying when pulling. That is good info HRD. Appreciate you sharing it. I have driven several 5.7 trucks and did not care for them because of the high rpm needed to get them to move anc constantly hunting gears. Your recipe seems like it might be the answer to nice driving cheaper truck- and I am all about cheap. Will the 5.7 computer and electronics run this setup without any aftermarket stuff? Did you get a tune done on it? Are you running the eagle 5.7 heads or will the older ones work?
Last edited by mgoblue9798; 02/09/22 01:39 PM.
|
|
|
Re: Difference in 5.7 or 6.4
[Re: mgoblue9798]
#3013712
02/09/22 01:44 PM
02/09/22 01:44 PM
|
Joined: Jan 2005
Posts: 12,419 Kalispell Mt.
HotRodDave
I Live Here
|
I Live Here
Joined: Jan 2005
Posts: 12,419
Kalispell Mt.
|
All factory 5.7 top end engine parts, just about everything above the head gaskets (needs 6.4 head gaskets) is factory 5.7. I did not tune anything, it would set lean codes with the 5.7 injectors so I got a set of fleabay used 6.4SRT8 injectors and no more lean codes. The 5.7 and 6.4 TRUCK engine use the same injectors you need the SRT8 injectors.
It results in more cylinder pressure with the small cam and small chambers of the 5.7 heads, I put the ex valves in the drill press and mirror polished them to keep em from being as hot. There is no sign of detonation on the plugs, audibly or on the knock sensors in the data stream even on 87 octane.
I bought a set of long tube headers today on craigslist that hopefully fit and give me even more giddy up, Ill post up the results if they fit.
I am not causing global warming, I am just trying to hold off a impending Ice Age!
|
|
|
Re: Difference in 5.7 or 6.4
[Re: mgoblue9798]
#3013714
02/09/22 01:47 PM
02/09/22 01:47 PM
|
Joined: Jan 2005
Posts: 12,419 Kalispell Mt.
HotRodDave
I Live Here
|
I Live Here
Joined: Jan 2005
Posts: 12,419
Kalispell Mt.
|
I would not run the early 5.7 heads as they will lower compression quench and flow... I am running eagle 5.7s that give it more compression. If you really want to run the early heads then you should get an SRT short block because of the dome pistons.
I am not causing global warming, I am just trying to hold off a impending Ice Age!
|
|
|
Re: Difference in 5.7 or 6.4
[Re: HotRodDave]
#3013730
02/09/22 02:33 PM
02/09/22 02:33 PM
|
Joined: Mar 2010
Posts: 1,061 Atlanta, GA
mgoblue9798
super stock
|
super stock
Joined: Mar 2010
Posts: 1,061
Atlanta, GA
|
I would not run the early 5.7 heads as they will lower compression quench and flow... I am running eagle 5.7s that give it more compression. If you really want to run the early heads then you should get an SRT short block because of the dome pistons. Dont the 6.4 hemi truck engines have sodium filled exhaust valves? Could they be swapped into the 5.7 eagle head?
|
|
|
Re: Difference in 5.7 or 6.4
[Re: mgoblue9798]
#3013733
02/09/22 02:41 PM
02/09/22 02:41 PM
|
Joined: Jan 2005
Posts: 12,419 Kalispell Mt.
HotRodDave
I Live Here
|
I Live Here
Joined: Jan 2005
Posts: 12,419
Kalispell Mt.
|
yes I think they do but pretty sure they are also a larger diameter I think, you could probably swap them with a valve job to open the seat or just machine em to the smaller diameter maybe. It don't really seem needed to me because they don't cause any issues the way I am running it. I suspect it was done to keep from getting hot thereby reducing NOX formation. Buying a set and machining to fit defeats the low buck/super simple idea some.
I am not causing global warming, I am just trying to hold off a impending Ice Age!
|
|
|
Re: Difference in 5.7 or 6.4
[Re: HotRodDave]
#3013823
02/09/22 06:31 PM
02/09/22 06:31 PM
|
Joined: Jan 2003
Posts: 5,784 Corpus Christi, TX
shanker
master
|
master
Joined: Jan 2003
Posts: 5,784
Corpus Christi, TX
|
The 6.4 tows better, more about the TQ than the HP, a 5.7 downshifts a lot without a trailer, my 6.4 (not exactly stock) pulls way better than a 5.7. I actually buy 5.7 trucks with bad engines and stick 6.4s in with a simple upgrade recipe that is much better than even a stock 6.4.
If your willing to build a truck up the best combo seems to me to use a 6.4 truck short block, 6.4 SRT8 injectors with 5.7 heads, intake cam... as the 5.7s make more TQ per CID than the 6.4. This also gives you more compression than a regular 6.4 truck and is a beast for towing, I currently have this exact combo in my 2011 4x4 4 door long bed and towed an identicle configuration truck on a heavy 20ft tilt-deck trailer and even going up a couple big mountain grades only un-locked the TQ converter and did not downshift. I got 11.5 MPG towing that truck. It pulls even better than an actual stock 6.4 truck and cost about 1/2 what one of those trucks would cost. The real 6.4 trucks use EGR witch I hate, the 5.7s don't have it.
I did one with a 6.4 SRT8 engine and it pulled even better but it liked to run much higher RPM also, this current one is much more satisfying when pulling. sounds like a great combo...sure would love to see what kind of #'s it puts down on a chassis dyno.
The Federal Government has not yet learned that you cannot legislate morality
1970 Coronet R/T FF4/FF8/V85/V1G 440/Auto/3.23
1970 Coronet R/T FK5/FK5/V8W/V1W 440/Auto/3.55
1970 Super Bee TX9/TX9/V8W/N96 383/Auto/3.91
1975 Duster 360 VS29L5 Daily Driver
|
|
|
Re: Difference in 5.7 or 6.4
[Re: Smoparmike]
#3014262
02/11/22 10:59 AM
02/11/22 10:59 AM
|
Joined: Jan 2003
Posts: 43,603 Round Lake Beach, Illinoisy
Rhinodart
Rhinotruck
|
Rhinotruck
Joined: Jan 2003
Posts: 43,603
Round Lake Beach, Illinoisy
|
I chose the 5.7 because in 2015 it didn't have MDS and I didn't want extra parts that may fail. Also, they recommend premium fuel for the 6.4 when towing, didn't want that cost either! I have 326K miles on my truck now with only the typical exhaust manifold studs breaking, they eventually had to replace the manifold. Only other issues were the water pump and of course the transmission had to be replaced at 280K. 90% of the mileage was towing an 18' open, 24' enclosed, or 32' LQ trailer and I will say that the 5.7 is adequate, not great for towing the larger trailers. I am glad I didn't buy the 6.4 with the amount of fuel I have bought over the last 6 years...
The funny thing about science is that if you change one miniscule parameter you change the entire outcome to the way you want it.
JB Rhinehart, Realist
A-Body's RULE!
|
|
|
Re: Difference in 5.7 or 6.4
[Re: hemi70se]
#3014371
02/11/22 02:54 PM
02/11/22 02:54 PM
|
Joined: Jan 2005
Posts: 12,419 Kalispell Mt.
HotRodDave
I Live Here
|
I Live Here
Joined: Jan 2005
Posts: 12,419
Kalispell Mt.
|
If you are on a tighter budget and want a newer Ram truck why not look into a repaired "prior salvage" one? You said you would likely have it a long time. That way you can get a better newer truck with less miles on it. I have been building and driving them for 10 years now. Great value! Why spend 30K for a clean title one with 100K miles, Instead spend 30K for one with only 30k miles that will give you years of service before needing anything replaced. They aren't all total nasty wrecks that need fixing either. I had an 18 2500 Cummins with 44k on it last year that someone put in the ditch and bent the front axle. No paint or body damage at all. Replaced the front axle and did alignment and it was good to go! Not everyone putting trucks together is doing a good job, that's why they are so frowned on. Some guys will replace an entire crushed wiring harness for example while others will cut and splice a mess of wires just twisting them together, some guys pull all the old broken plastic out of hard to reach places while others leave it in there to cause unidentified rattles for the next 20 years. Some guys use paint that outlasts the factory paint (VERY RARE!) other guys use the cheapest stuff they can get a paint match on and don't prime it properly and it flakes off in a year (VERY COMMON). Even down to things likt the diff you mention, some rebuilders find a good comparable mileage diff to stuff under it and others grab one with 300,000 miles and pressure wash it and throw some THICK gear oil in to quiet the thing down long enough to sell. I would not say to never buy one but it is a case of "buyer be ware" for sure.
I am not causing global warming, I am just trying to hold off a impending Ice Age!
|
|
|
Re: Difference in 5.7 or 6.4
[Re: HotRodDave]
#3014413
02/11/22 04:46 PM
02/11/22 04:46 PM
|
Joined: May 2003
Posts: 2,483 Minneapolis, MN
hemi70se
top fuel
|
top fuel
Joined: May 2003
Posts: 2,483
Minneapolis, MN
|
Oh, I hear ya. I see plenty of guys that like to cut corners on repairs. I would just say to ask plenty of questions and get a feel for IF they cut corners or have a pro inspect a possible purchase. I get plenty of repeat customers and referrals because I do things right. No aftermarket parts, and drivetrain parts that are similar or less miles. I just fixed a 2018 Cummins that got sunk 4 ft in a pond. Sucked water into 1 cylinder so I replaced the engine with one with only 39K on it (truck had 46k). replaced every single electronic part and wiring. Brand new dash and full cab harnesses to the tune of over $1200 alone. I had an 18 Ram 3500 6.4 shortbed that got hit hard in the front, only 18k miles., Big Horn. Bought it for only $8,100. I bought a brand new frame for it for $2100 along with new Mopar fenders, hood, and RH doors. Sold it about when the pandemic started. I'm sure the guy that bought it is quite happy with it.
|
|
|
Re: Difference in 5.7 or 6.4
[Re: hemi70se]
#3014512
02/11/22 09:01 PM
02/11/22 09:01 PM
|
Joined: Mar 2010
Posts: 1,061 Atlanta, GA
mgoblue9798
super stock
|
super stock
Joined: Mar 2010
Posts: 1,061
Atlanta, GA
|
Oh, I hear ya. I see plenty of guys that like to cut corners on repairs. I would just say to ask plenty of questions and get a feel for IF they cut corners or have a pro inspect a possible purchase. I get plenty of repeat customers and referrals because I do things right. No aftermarket parts, and drivetrain parts that are similar or less miles. I just fixed a 2018 Cummins that got sunk 4 ft in a pond. Sucked water into 1 cylinder so I replaced the engine with one with only 39K on it (truck had 46k). replaced every single electronic part and wiring. Brand new dash and full cab harnesses to the tune of over $1200 alone. I had an 18 Ram 3500 6.4 shortbed that got hit hard in the front, only 18k miles., Big Horn. Bought it for only $8,100. I bought a brand new frame for it for $2100 along with new Mopar fenders, hood, and RH doors. Sold it about when the pandemic started. I'm sure the guy that bought it is quite happy with it. It is all about who does the repairs. We used to buy totaled vehicles at the sale and rebuild them at the shop. Lots of money to be saved as you mention, but if you buy from the wrong rebuilder there is a lot to lose as well. Been thinking about going to the sale again as that is the only way I will ever be able to afford a newer truck.
|
|
|
Re: Difference in 5.7 or 6.4
[Re: hemi70se]
#3014513
02/11/22 09:02 PM
02/11/22 09:02 PM
|
Joined: Jan 2003
Posts: 43,603 Round Lake Beach, Illinoisy
Rhinodart
Rhinotruck
|
Rhinotruck
Joined: Jan 2003
Posts: 43,603
Round Lake Beach, Illinoisy
|
I just bought a 2015 2500 Cummins Ram with 265K on it and it was a one owner trade from the dealer who sold it to him originally so they had ALL the fixes it ever needed in their database and they even printed it out for me! $20K out the door including all the taxes, title, and all other charges. They even gave me a lifetime powertrain warranty for $700, which I will use as soon as I toast the transmission...LOL!
The funny thing about science is that if you change one miniscule parameter you change the entire outcome to the way you want it.
JB Rhinehart, Realist
A-Body's RULE!
|
|
|
Re: Difference in 5.7 or 6.4
[Re: HotRodDave]
#3014862
02/12/22 11:16 PM
02/12/22 11:16 PM
|
Joined: Jan 2003
Posts: 1,967 ID/MT
Cheeto
top fuel
|
top fuel
Joined: Jan 2003
Posts: 1,967
ID/MT
|
[quote=hemi70se] ...
Not everyone putting trucks together is doing a good job, that's why they are so frowned on. ... This! I've done rebuilds off and on for about 15 years. There's some seriously shady cats running around those auctions. If you are or you have a good mechanic/bodyman doing the work they can save some serious coin over buying retail. I stayed with stuff that was 10-15 years old at the time and mostly bought low mileage stuff for my driver then sold it after a few months for a small ($1000-$3000) profit. I got to enjoy something nice for a while and the next guy got a great deal. I took before/after pics and was very up front about what I did to them. It was/is more of a hobby than a moneymaker for me. Couple years back I swapped over to UTVs but now even the auction prices have gone nuts. On a side note, HotRodDave I'll like to PM you about doing some work on a car I have sitting in Libby but you're "over your private topic limit".
Last edited by Cheeto; 02/12/22 11:19 PM.
Cheeto It's not perfect. It's not correct. It's not yours!
|
|
|
Re: Difference in 5.7 or 6.4 UPDATE
[Re: Rhinodart]
#3027322
03/25/22 10:04 AM
03/25/22 10:04 AM
|
Joined: Jan 2004
Posts: 369 Bowler Wisconsin
Smoparmike
OP
enthusiast
|
OP
enthusiast
Joined: Jan 2004
Posts: 369
Bowler Wisconsin
|
I need to look in Illinois! I'm in North Central Wisconsin where they use salt 9 months of the year. The only 2500 diesels I see around here for $20,000 are 20 years old or older and full of Wisconsin rust or it has a 12in stack coming out of the bed. I have been only looking on craigslist & marketplace. I did find a 2012 2500 gas 142,000 no rust stored winters aftermarket wheels looks really nice and he wants $26,000 just seems like a lot of money.
Last edited by Smoparmike; 06/27/22 11:19 AM.
|
|
|
|
|