Page 1 of 20 1 2 3 19 20 >
Topic Options
#1369872 - 01/15/13 09:58 AM Gen III Hemi, please post things to avoid and know..
gregsdart Offline
master

Registered: 01/21/03
Posts: 8060
Loc: Frostbitefalls (Rocky&Bullwink...
Mods, can we make a sticky of this, then move it to the archives for all to access?
Feel free to add to this list, or disagree IF you have first hand knowledge of more than one motor having problems with suggested practices/parts..
Things like-
Use a 6.1 oil pump instead of a stock 5.7. The 5.7 is marginal, as noted by spun bearings on many used motors.
Bleed the heads to make sure there is coolant in them before fireup.
6.1 pushrods are .050(?) longer than 5.7 pushrods
5.7 stock motors have limited valve to piston clearance (how little? duration?)
Best controller for a swap?
Do not use a cross drilled crank for a high rpm build.
Edit; additional info-
All Gen III Hemis use a LOT less timing!


Edited by Al_Alguire (01/05/15 11:51 AM)

Top
#1369873 - 01/15/13 12:32 PM Re: Gen III Hemi, please post things to avoid,,,,,,,,, [Re: gregsdart]
cagebob1 Offline
enthusiast

Registered: 12/22/09
Posts: 243
Loc: Mesa, AZ

Top
#1369874 - 01/16/13 09:10 AM Re: Gen III Hemi, please post things to avoid,,,,,,,,, [Re: gregsdart]
tboomer Offline



Registered: 01/20/03
Posts: 21648
Loc: The frozen wasteland of Iowa
For ya,Greg! If we can get enough info,we can stick this into the archives..

Top
#1369875 - 01/16/13 09:45 AM Re: Gen III Hemi, please post things to avoid,,,,,,,,, [Re: tboomer]
540challenger Offline
master

Registered: 04/22/07
Posts: 2770
Loc: NY usa
problem with this we will have to revise the info, alot of stuff is still being learned the newer 6.4 and 5.7 vct might throw a curve ball on some info but it would be nice to have what info is out there

Top
#1369876 - 01/16/13 09:46 AM Re: Gen III Hemi, please post things to avoid,,,,,,,,, [Re: tboomer]
Guitar Jones Offline
master

Registered: 12/18/09
Posts: 8746
Loc: in a cattle trailer down by th...
When I asked on here about the costs of building a 650 - 700 HP Gen III I got squat for answers. Even though guys that know responded to the post. So it would appear that the guys that do know these engines aren't willing to talk much about their secrets. These engines are not going to move into the mainstream if information isn't shared. Then parts availability will be curtailed. Mopar guys have always complained about performance parts and what is available to them so to me, this line of thinking is counter productive.

Just my
_________________________
W5 408 cid, 1.324, 6.155 @ 110.34, 9.756 @ 134.67 with a broken converter hub. Oh yeah, it's all Mopar too, 904 trans and an 8.75 rear!!

Top
#1369877 - 01/16/13 10:49 AM Re: Gen III Hemi, please post things to avoid,,,,,,,,, [Re: Guitar Jones]
CHAPPER Offline
master

Registered: 11/05/09
Posts: 3399
Loc: Belpre,Ohio
My 'word of wisdom' is ,,,don't use a stock 5.7 crank if you are going to run over 6000RPM. I don't know just exactly where the cut-off point is, but I do know that 7500-7800 is too much.
_________________________
If you like drag racing, support your local track.

Top
#1369878 - 01/16/13 10:51 AM Re: Gen III Hemi, please post things to avoid,,,,,,,,, [Re: gregsdart]
74yellowduster Offline
member

Registered: 01/16/13
Posts: 167
Loc: maryland
i'm no expert... however i was reading another thread, and they had not timed it properly / tuned it. it was even tested with the advance to be comparable to old school mopars ~mid 30's total. the guy's engine eventually blew. someone else claimed that the new hemis only use around 24 degrees advance. beware! do your research before you end up with trouble.

here is the thread:

http://www.cuda-challenger.com/cc/index.php?topic=28465.435
the problem is shown (with pics) around page 30

dont quote me on how to set the timing on the new gens, but please check before you run it. dont trust that your box has a "knock sensor" or something.

Top
#1369879 - 01/16/13 11:04 AM Re: Gen III Hemi, please post things to avoid,,,,,,,,, [Re: 74yellowduster]
gregsdart Offline
master

Registered: 01/21/03
Posts: 8060
Loc: Frostbitefalls (Rocky&Bullwink...
Anybody care to propose a max timing starting point, say, 22 degrees? We also need education on what timing curve to use.


Edited by gregsdart (01/16/13 11:05 AM)
_________________________
GREG
Educated at SHK U
Measure with yardstick
mark with chalk
cut with torch!



528 cubic inch alky injected 440-1 wedge, 3055 race weight.
8.779 at 153.16 mph. 1.289 60 ft. density altitude 1617 feet. Best 60 ft 1.24

Top
#1369880 - 01/16/13 11:30 AM Re: Gen III Hemi, please post things to avoid,,,,,,,,, [Re: gregsdart]
AlexP Offline


Registered: 09/08/03
Posts: 10554
Loc: Houston, Tx
Quote:

Mods, can we make a sticky of this, then move it to the archives for all to access?
Feel free to add to this list, or disagree IF you have first hand knowledge of more than one motor having problems with suggested practices/parts..
Things like-

Use a 6.1 oil pump instead of a stock 5.7. The 5.7 is marginal, as noted by spun bearings on many used motors.

I agree with that. 6.1 timing set is better too.

Bleed the heads to make sure there is coolant in them before fireup.

Bleed it with the coolant cap. Let it get to about temp and crack the cap every 30 seconds until no more air comes out.

6.1 pushrods are .050(?) longer than 5.7 pushrods

Correct. Most aftermarket cams are ground on a 6.1 core, so use 6.1 pushrods.

5.7 stock motors have limited valve to piston clearance (how little? duration?)

About 219/223 is the most you will need and will fit.

Do not use a cross drilled crank for a high rpm build.

No reason to use anything but a stock 6.1 crank.




Top
#1369881 - 01/16/13 11:40 AM Re: Gen III Hemi, please post things to avoid,,,,,,,,, [Re: AlexP]
RodStRace Offline
I Live Here

Registered: 09/21/05
Posts: 12383
Loc: Chino Valley
do not run them lean!
A friend put in a conversion and used an external pump that couldn't keep up. Detonation and the top of the pistons separating was the result above 4500!

Top
#1369882 - 01/16/13 11:43 AM Re: Gen III Hemi, please post things to avoid,,,,,,,,, [Re: RodStRace]
AlexP Offline


Registered: 09/08/03
Posts: 10554
Loc: Houston, Tx
The ring lands will break at the slightest bit of detonation.

I've seen a 6.1 with 8 broken pistons that didn't have chewed up valve seats or even a misfire code. The parts were all trapped in the cats.

Top
#1369883 - 01/16/13 11:55 AM Re: Gen III Hemi, please post things to avoid,,,,,,,,, [Re: gregsdart]
lowflyingdart Offline
mopar

Registered: 03/05/04
Posts: 528
Loc: Oak Grove, MN
Quote:

Anybody care to propose a max timing starting point, say, 22 degrees? We also need education on what timing curve to use.




19 Degrees to start, no more than 26 degrees with good fuel.
_________________________
"I have not failed. I've just found 10,000 ways that won't work." Thomas A. Edison

Top
#1369884 - 01/16/13 12:04 PM Re: Gen III Hemi, please post things to avoid,,,,,,,,, [Re: AlexP]
FastmOp Offline
master

Registered: 01/20/03
Posts: 4875
Loc: Hot Rod Ridge
Mine has 17,000 miles on it now. 10,000 with the procharger, there able to handle good power. Mine is 500hp to the wheels after the TTI install.
Your not going to get much help on this board. Most here just want to tell you how bad the new stuff is.

Top
#1369885 - 01/16/13 12:05 PM Re: Gen III Hemi, please post things to avoid,,,,,,,,, [Re: AlexP]
MattW Offline
top fuel

Registered: 06/02/05
Posts: 2462
Loc: Ontario Canada
Quote:

Quote:

Mods, can we make a sticky of this, then move it to the archives for all to access?
Feel free to add to this list, or disagree IF you have first hand knowledge of more than one motor having problems with suggested practices/parts..
Things like-

Use a 6.1 oil pump instead of a stock 5.7. The 5.7 is marginal, as noted by spun bearings on many used motors.

I agree with that. 6.1 timing set is better too.

Bleed the heads to make sure there is coolant in them before fireup.

Bleed it with the coolant cap. Let it get to about temp and crack the cap every 30 seconds until no more air comes out.

6.1 pushrods are .050(?) longer than 5.7 pushrods

Correct. Most aftermarket cams are ground on a 6.1 core, so use 6.1 pushrods.

5.7 stock motors have limited valve to piston clearance (how little? duration?)

About 219/223 is the most you will need and will fit.

Do not use a cross drilled crank for a high rpm build.

No reason to use anything but a stock 6.1 crank.








What do we want in this thread????
What Parts Interchange?
CC of the 5.7 6.1 5.7 eagle 6.4 appache?
Stroke of stock crank?
5.7 block strengh vs 6.1 6.4?
Oiling mods, this I would personally like to see in a diagram. The G3 is a carbon copy of the LS until the oil get to the lifters. How the hell is Stock cross drilled crank meesing all this up? Isn't the LA base engine using a cross drill crank? Wouldn't this be happening to them too?
Most successful G3 are rpm limited.
I do agree that when this oiling issues is resolved the sky is the limit.
Look at all the post on small block heads flow #. A stock unported eagle will put most of them to shame.
Now only IF we could get the lower end to survive.

Top
#1369886 - 01/16/13 12:10 PM Re: Gen III Hemi, please post things to avoid,,,,,,,,, [Re: MattW]
MattW Offline
top fuel

Registered: 06/02/05
Posts: 2462
Loc: Ontario Canada
I wonder if Mr Sanborn AKA 40ford has done any experimenting with the G3?

Top
#1369887 - 01/16/13 04:33 PM Re: Gen III Hemi, please post things to avoid,,,,,,,,, [Re: MattW]
AlexP Offline


Registered: 09/08/03
Posts: 10554
Loc: Houston, Tx
Stay away from Manley Nextek Springs.

Use a PSI or a PAC..Something premium.

Top
#1369888 - 01/16/13 07:11 PM Re: Gen III Hemi, please post things to avoid,,,,,,,,, [Re: AlexP]
gregsdart Offline
master

Registered: 01/21/03
Posts: 8060
Loc: Frostbitefalls (Rocky&Bullwink...
Thanks a lot for the input, guys. The more the better. When we get a larger amount of info, I will try to transfer it to my first post after the "EDIT"
_________________________
GREG
Educated at SHK U
Measure with yardstick
mark with chalk
cut with torch!



528 cubic inch alky injected 440-1 wedge, 3055 race weight.
8.779 at 153.16 mph. 1.289 60 ft. density altitude 1617 feet. Best 60 ft 1.24

Top
#1369889 - 01/16/13 07:38 PM Re: Gen III Hemi, please post things to avoid,,,,,,,,, [Re: AlexP]
hemidup Offline
super stock

Registered: 11/19/08
Posts: 833
Loc: MN
Nuttin a matter with Manley NexTek springs. The only G3 Hemi springs we use. For those that can rev these engines to 8G plus use the Manley 221430 or PAC 1409. Both have high spring rates.
_________________________
Jerry Williams.

Top
#1369890 - 01/17/13 05:39 AM Re: Gen III Hemi, please post things to avoid,,,,,,,,, [Re: gregsdart]
gregsdart Offline
master

Registered: 01/21/03
Posts: 8060
Loc: Frostbitefalls (Rocky&Bullwink...
Do the Gen III Hemis use throw away stretch to yield bolts? Where?
I see a lot of the gaskets appear to be reusable. Please post your experiences.
How good/bad is the stock timing chain? Good low priced alternative? High hp high rpm alternative?
At what point do tie bars for the rocker shafts start to really show a hp gain?
The Hemi heads flow so well, the reaction to various cams must be different than say a stock small block. Anyone care to share what they know about duration,ICA and LSA?
Can the new Hemi heads run a higher compression ratio in comparison to an aluminum head small block?
_________________________
GREG
Educated at SHK U
Measure with yardstick
mark with chalk
cut with torch!



528 cubic inch alky injected 440-1 wedge, 3055 race weight.
8.779 at 153.16 mph. 1.289 60 ft. density altitude 1617 feet. Best 60 ft 1.24

Top
#1369891 - 01/17/13 06:07 AM Re: Gen III Hemi, please post things to avoid,,,,,,,,, [Re: MattW]
gregsdart Offline
master

Registered: 01/21/03
Posts: 8060
Loc: Frostbitefalls (Rocky&Bullwink...
Quote:

Quote:

Quote:

Mods, can we make a sticky of this, then move it to the archives for all to access?
Feel free to add to this list, or disagree IF you have first hand knowledge of more than one motor having problems with suggested practices/parts..
Things like-

Use a 6.1 oil pump instead of a stock 5.7. The 5.7 is marginal, as noted by spun bearings on many used motors.

I agree with that. 6.1 timing set is better too.

Bleed the heads to make sure there is coolant in them before fireup.

Bleed it with the coolant cap. Let it get to about temp and crack the cap every 30 seconds until no more air comes out.

6.1 pushrods are .050(?) longer than 5.7 pushrods

Correct. Most aftermarket cams are ground on a 6.1 core, so use 6.1 pushrods.

5.7 stock motors have limited valve to piston clearance (how little? duration?)

About 219/223 is the most you will need and will fit.

Do not use a cross drilled crank for a high rpm build.

No reason to use anything but a stock 6.1 crank.








What do we want in this thread????
What Parts Interchange?
CC of the 5.7 6.1 5.7 eagle 6.4 appache?
Stroke of stock crank?
5.7 block strengh vs 6.1 6.4?
Oiling mods, this I would personally like to see in a diagram. The G3 is a carbon copy of the LS until the oil get to the lifters. How the hell is Stock cross drilled crank meesing all this up? Isn't the LA base engine using a cross drill crank? Wouldn't this be happening to them too?
Most successful G3 are rpm limited.
I do agree that when this oiling issues is resolved the sky is the limit.
Look at all the post on small block heads flow #. A stock unported eagle will put most of them to shame.
Now only IF we could get the lower end to survive.




My intent for this thread is to be a go to resource for anyone that wants to buy,modify,swap into another car or build a new Hemi. So EVERYTHING relevant to working on these motors is important,
The Gen III Hemis have the same bellhousing pattern as a small block, save for the top bolt which is not used.
There are left side starters, and right side starters, and the older style transmissions like a 904 or 727 etc need a special flex plate available from Ma Mopar. A compact newer style small block starter will work for a 904, etc. Crank to converter distance and crank bolt pattern is not the same.
The heads on the Hemi are wide enough to require a little bit of clearancing on EARLY A bodys on the passenger side.
The low mount alternator also requires some modification for clearance of the stock frame rail on the passenger side.
There are some clearance issues with the oil filter in the early As as well, but fixable.
SRT8 Jeep manifolds are about all that will work on the early A body swaps, for best results.
An Altercation type front suspension that eliminates the torsion bars helps a lot on the Early A chassis for exhaust options.
_________________________
GREG
Educated at SHK U
Measure with yardstick
mark with chalk
cut with torch!



528 cubic inch alky injected 440-1 wedge, 3055 race weight.
8.779 at 153.16 mph. 1.289 60 ft. density altitude 1617 feet. Best 60 ft 1.24

Top
Page 1 of 20 1 2 3 19 20 >

Advertisement
Sponsored Link
Forum Stats
24,899 Registered Members
32 Forums
184,275 Topics
2,134,947 Posts

Most users ever online: 882 @ 03/05/17 10:15 PM
Moparts Newest Topics
Carburetor spacers for heat
by RAY1969CARS
10/20/17 10:35 PM
Question about SVO rear brakes, Dana S60, Dr. Diff/Strange
by TomsCharger70
10/20/17 10:27 PM
Stamped number on car
by toplescuda
10/20/17 10:12 PM
how to remove accelerator cable from the floor
by moparpro
10/20/17 08:04 PM