5.7 0r 6.1 with msd hemi 6 and carb

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swifter

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If anyone does this swap let me know what your final total timing is set at,Just want to compare notes with someone else. Swifter
 
These are the factory MBT timing tables. These timing values represent the Mininmum timing advance that delivers the Best Torque.[MBT] These values also assume that the engine is NOT knock limited in any way ei: its using high octane fuel.
The PCM uses these values as a CAP or MAX to the final timing.
WOT timing for pump gas is usually a couple degrees lower.

Unless you're on a dyno measuring the HP gain/loss of timing adjustments while monitoring Knock, I'd NEVER go any higher than these values.

2005 5.7L
MBT_05_57.jpg

2007 6.1L
MBT_07_61.jpg
 
Where are those charts from???? MSD???? Or stock timing charts--btw-When we ran my 70 duster with my 5.7 conversion we stopped adding timing at 39 degrees and we were still making hp gains took it up to 42 degrees and still making power but backed it off a few degrees,We read the plugs every pull on the dyno and no signs of detonation on the plugs or any knocking issues hence why I asked anyone else with this particular set-up,I don't need any speculation,I need someone with the same conversion --xv intake,Cam,Springs,650 quick fuel carb,TTI headers,Hemi-6 controller thanks Steve
 
Steve

I assure you that +39 degrees on a 5.7L, ANY 5.7, is folly.

I've tuned plenty of high HP N/A 5.7L/6.1L and none have produced appreciable hp too much past ~30 degrees(w/ 110 octane)

You are either overlooking the signs of detonation and/or running an excessively RICH A/F.
 
myduster360 , so if you have a msd6hemi you can just copy those timing tables into it and it will run like stock ?
 
DODGESTRIKE said:
myduster360 , so if you have a msd6hemi you can just copy those timing tables into it and it will run like stock ?
Click to expand...

The table values are a good reference but I'd be carefull about doing a straight copy/paste.

On a new engine, I'd drop the whole table down at least 3-5 degrees as a good starting point.


The stock PCM is infinately more sophisticated in its timing control than the MSD so, No, I doubt it ever run "as good as stock".

With that said, its a better starting point than a complete guess.
 
ok but its good to have a starting point , ive searched but havent found a lot about timing on these 3ghemi engines
 
yes it is , im going to start from scratch and its going to be useful

thanks myduster360:rock:
 
28 Degrees only? I would test it on a chassis, but use a total of 36 and do changes in 2 degree increments until you get max power. With the hemi chambers and the aluminium heads it should be ok with lots of timing just use the correct octane rating for your compression ratio.
 
I'm with myduster here the combustion chamber design of the 3g hemi doesn't require anywhere near as much timing as you would think if the afr is in the correct range for the combo. N/A 5.7 should be around 12.8-13.0 wot afr and around 28-29 degrees for peak mbt.
 
Mr Hemi said:
28 Degrees only? I would test it on a chassis, but use a total of 36 and do changes in 2 degree increments until you get max power. With the hemi chambers and the aluminium heads it should be ok with lots of timing just use the correct octane rating for your compression ratio.
Click to expand...

By all means test it. I seriously doubt you'll see much hp increase over 30 degrees. I generally stop adding timing if the hp gain is less than 5hp.

Remmember that these aren't decades old engine designs. No benefit in transfering outdated LA tuning methodology. The combustion chambers are specifically designed for the fastest burn possible.

I would love to see you testing results regardless.
 
OK not to bust your bubble--But we referenced the tdc on number 1 cy. and added timing tape to the crank pulley added spark plug wires to the #1 coil and timed the motor to make sure that the hemi 6 controller was reading timing correctly with a digital timing light and confirmed our readings because the Dyno tuner was beside himself as to the amount of timing that this motor was taking,MSD techs were completely useless to us and told me I had a very inefficient motor!!!! Let me ask you guy's this,If you know about detonation where does this show up first????? Answer---On the Spark plugs correct????? I'm looking for help here--so don't tell me what I don't have Steve
 
I also went to the extreme as to pull the whole front of the motor apart to make sure the timing chain/marks were correct trying to find why,Also had one of the top tuners here in Wisconsin drove 5 hrs to help us with a timing curve for this motor and made several curves we loaded in the hemi-6 to try result---THE MORE TIMING WE GAVE IT THE MORE IT LOVED IT Steve
 
You don't suppose maybe one of the wiring harness plugs might be off? Like maybe two of the coils have their plugs swapped?
 
1) You're being very rude to those offering advice
2) Everyone from MSD to the your builder along with many in this thread believe +39 degrees is excessive. You have something F'ed up. You're in denial if you insist you don't.
3) The cam position has little to do with the final timing value. So ripping the front of the engine off was a complete waste of TIME(lol pun intended) Hint: its on the crank, IN the engine)
 
Post your .ign file and I'll look it over.
Did you have MSD look over the file?
Are you running the MAP to the MSD?
What coils are you using?
What year is the engine?
 
I sent the box in to MSD to have them check it out
Msd will not suggest any changes to the files---liability issues was there answer
Yes map sensor connected
Stock ignition coils
O6 out of a durango--8,000 miles on it
I'm not rude at all,I posted here when these issues where going on and no help was here
So what your telling me is the timing chain/gears could not be off and cause excessive timing?? HUM

Any help on this is very much appreciated,Just don't tell me what I don't have,The more timing we gave it,the more it liked it that is a fact. Have you worked on one with a carb??

Before i took it to the Dyno tuner the car fell flat on its face at 4,000 rpm and then would recover and then go like a bat out of hell,This burp was removed when they bumped up the timing and changed the jets in the carb

I would be glad to post the ign. file How????

Thanks Steve
 
swifter said:
I sent the box in to MSD to have them check it out
Msd will not suggest any changes to the files---liability issues was there answer
Yes map sensor connected
Stock ignition coils
O6 out of a durango--8,000 miles on it
I'm not rude at all,I posted here when these issues where going on and no help was here
So what your telling me is the timing chain/gears could not be off and cause excessive timing?? HUM

Any help on this is very much appreciated,Just don't tell me what I don't have,The more timing we gave it,the more it liked it that is a fact. Have you worked on one with a carb??

Before i took it to the Dyno tuner the car fell flat on its face at 4,000 rpm and then would recover and then go like a bat out of hell,This burp was removed when they bumped up the timing and changed the jets in the carb

I would be glad to post the ign. file How????

Thanks Steve
Click to expand...

Timing is referenced straight off the crank sensor which in turns reads the cranks trigger wheel. All the cam sensor does is tell the PCM when #1 is on the power stroke. After the engine rotates 2 revolutions and fires, you don't even need a cam sensor or to know where the cam is relative to the crank.

What was the A/F at WOT as read off the Dyno's wideband?
Excessively rich A/F needs an excessive amount of timing.

What was the HP and Trq with 39 degrees of timing?

post your file using depositfiles.com


ps: a carb is the worse thing you can do to a 3gen Hemi
stock LX 5.7l intake is worth +40Hp and +45 ft-lb over the MP 4 barrel intake:
 
Hp at the wheels (mustang chassis dyno) was 346 @ 5355 rpm--he was afraid to pull it past 6000 rpm and at 5400 was still gaining hp

torque was at 321 @ 5355 rpm

Fuel ratio was at 13.1 at w.o.t

Thanks for the interest!!!!

Explain why a carb is so bad for the 3rd gen hemi-- Ever see the video of hemijoe's carbed 5.7 3rd gen??
 
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