Less timing equals more power.

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JoeDust451

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I'm finding out this magnum engine runs stronger with less timing, right now i have it at 10* int. 31-32* total, & its all coming in late, a good 3500+ rpms, the other day i decided to run it up to 12* int., it didn't like it, i'm going to try 8* int. to see what happens, i'm running on 87 octane, it just amazes me how well these magnums run with literly "no" timing. I can hardly get the MT DRs to hook lol.
 
I do beileve it's the chambers fault. LOL
 
JoeDust451 said:
I'm finding out this magnum engine runs stronger with less timing, right now i have it at 10* int. 31-32* total, & its all coming in late, a good 3500+ rpms, the other day i decided to run it up to 12* int., it didn't like it, i'm going to try 8* int. to see what happens, i'm running on 87 octane, it just amazes me how well these magnums run with literly "no" timing. I can hardly get the MT DRs to hook lol.
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I agree, My magnum headed 408 made the most HP with 30* total timing. It lost power running the normal 34-35* or so the LA heads like.
 
I run 32-33 on my magnum headed 360 with 18 initial with it all in at 2800 rpm.

The initial timing an engine needs is mostly determined by the amount of overlap in the cam. The total is mostly determined by the efficiency of chamber and port design. The new hemi and LS engines run less than 30 degrees.
 
Badart said:
What are the specs on the motor?
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95 magnum, stock bottom end with a good 120xxx, RHS heads, re-ground bullet cam (.477/.477, 216/218 @50 on a 112. 1.6 rockers), summit headers, crosswind intake, 750 3310, Wysco dist., stock 904, stock converter, 3.73 gears. Tire fryin "MF" lol.
 
joeDust I have the same head you have...the 360X heads and I have 36 degrees locked out and I get a good amount of vacuum, but my cam might be the thing effecting it...the only real way is to dyno it and test the different degrees of timing.
 
dgc333 said:
I run 32-33 on my magnum headed 360 with 18 initial with it all in at 2800 rpm.

The initial timing an engine needs is mostly determined by the amount of overlap in the cam. The total is mostly determined by the efficiency of chamber and port design. The new hemi and LS engines run less than 30 degrees.
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Agreed.The magnum needs less timing due to the very efficient double quench chamber. It's fast buring thus less timing needed.
 
I'm sure if i had more cam i'd benefit from more timing, my next step will be a converter, about 26-2800 stall.
 
when things are matched [cyl psi/cam, thats all you need.

Mopar says so too.

and closed chambers require less anyhow.

Thats why they always recommended 30* in their books, cause they are counting on YOU to build the right cam/compression combo.

they know their chambers
 
the lower the octane and the smaller the combustion space the less timing it needs becasue the lower octane's rate of burn is faster. Meaning the pressure builds much faster so less ignition lead to get the maximum pressure on the crank at the right time (in degrees or rotation). Longer strokes also mean less time as the piston dwells at TDC for a longer time and then accelerates away much faster.
 
74Burntorange said:
joeDust I have the same head you have...the 360X heads and I have 36 degrees locked out and I get a good amount of vacuum, but my cam might be the thing effecting it...
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MIGHT be? No, it IS the thing effecting it 74.
Where's the "smack forehead" smiley at?:-\"
 
74Burntorange said:
joeDust I have the same head you have...the 360X heads and I have 36 degrees locked out and I get a good amount of vacuum, but my cam might be the thing effecting it...the only real way is to dyno it and test the different degrees of timing.
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Jimacuda said:
MIGHT be? No, it IS the thing effecting it 74.
Where's the "smack forehead" smiley at?:-\"
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Why a competent engine builder would recommend that cam for the intended use is beyond me. It's a good 15-20* too long on duration at .050.

Sorry 74, it's not likely to ever run at an optimum level with that camshaft. The 36* locked out is a stop gap fix.

The nicer mag chambers do a better job than the old opens, that's for sure.
 
well the thing is when I want to stroke it, I wont need another cam or heads...
 
74Burntorange said:
well the thing is when I want to stroke it, I wont need another cam or heads...
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then you should have stroked it to begin with.....that big cam probably does not start making any hp or torque until 4000 rpm.....and idles terrible....
 
it idles fine...and ill stroke it when i get 1500...and I say we let it go now.. we all know its too big...
 
I've found that Mopars in general like less timing and more fuel...
 
I see this thread has leaned toward this guys cam being too big, how big is his cam?? The way everyone is talking, it must be a monster!

I'm going a different route with this combo of mine, keeping it as simple as possible, at this point, the only other installs will be a mild converter, MSD ignition box (dig. 6), window switch & some nitrous, my goal will be mid 7s in the 1/8.
 
JoeDust451 said:
I see this thread has leaned toward this guys cam being too big, how big is his cam?? The way everyone is talking, it must be a monster!

I'm going a different route with this combo of mine, keeping it as simple as possible, at this point, the only other installs will be a mild converter, MSD ignition box (dig. 6), window switch & some nitrous, my goal will be mid 7s in the 1/8.
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The bottom end is stock with a 120,000+ you put new heads on it and plan on spraying it,won't be long before it's huffing smoke or that motor comes apart..
 
its 260 at 50....for duration...All I asked for was help on getting it to run best with that cam in it...not for people telling me stuff I dont want to hear...I have plans on stroking but not right away..so leave it be already
 
stroked 340 said:
The bottom end is stock with a 120,000+ you put new heads on it and plan on spraying it,won't be long before it's huffing smoke or that motor comes apart..
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Well, it seems like you've either never ran nitrous, or you had a bad exsperience, i juiced the **** out of my 160xxx LT1 with a 100 shot, never an issue (& its a chebby), i have faith in mopars & nitrous, maybe you don't, most that have bad dealings with the bottle either start getting too greedy & don't tune for it, any stock bottom end will handle 100 shot all day long with no ill affects, even with miles on them, its been done quit often, if you have proper fuel/volume, pull timing accordingy, don't over-rev it, take all the proper precautions, should be just fine.
 
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