Timing request 100 shot 360

33IMP

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Reading the same type of posts on how fat the factory jets were is suprising.
Why have they not reposted leaner tunes?
Is there possibly a safe factor built into the old fat tubes helping keep you out of the lean territory in the event something went wrong?
Looking forward to p/u an a/f ratio assy. I'm interested in that w or w/o spray as it's just sounds like a gr8 idea.
Totally still learning here. Lots of studying
I believe several of the nitrous kit manufacturers have leaned out their recommended tunes, they are just not keen to tell their customers how off they were. As stated above, too fat can be just as bad as too lean, and I think the manufacturers realized their "safety margins" were too big.
 

71_dart_swinger

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I have aem wideband in mine. Makes things much easier. Also an adjustable return style fuel pressure regulator can help fine tune it into the appropriate AFR you want. Best to get it where you want running tits before the spray. I have nx plate. 175 pills 6.2 degrees of retard set info the digital 6al2 box. Runs right about 12.2-12.5 afr on the 175 shot. I have a aeromotive fpr on each of the fuel systems. I don’t care what base timing is. I set my timing at 36 deg at around 2400 rpm. Timing mark on the plug is dead center of the strap.
30EB2D84-6FA0-43BB-8989-2350795171B1.jpeg
 

360moparjunkie

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I have aem wideband in mine. Makes things much easier. Also an adjustable return style fuel pressure regulator can help fine tune it into the appropriate AFR you want. Best to get it where you want running tits before the spray. I have nx plate. 175 pills 6.2 degrees of retard set info the digital 6al2 box. Runs right about 12.2-12.5 afr on the 175 shot. I have a aeromotive fpr on each of the fuel systems. I don’t care what base timing is. I set my timing at 36 deg at around 2400 rpm. Timing mark on the plug is dead center of the strap. View attachment 1715572251
A wide band a/f appears to be in my future. Nice set up btw...one of my all time favorite motors.
Here is one of my plugs after a few 100 shot blasts at about 5-12 seconds per run. Not sure what to look for. There are tiny orange speckles on the porcelain next to the electrode. Any input appreciated.
20200803_070713.jpg
 

Ahoey

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I have aem wideband in mine. Makes things much easier. Also an adjustable return style fuel pressure regulator can help fine tune it into the appropriate AFR you want. Best to get it where you want running tits before the spray. I have nx plate. 175 pills 6.2 degrees of retard set info the digital 6al2 box. Runs right about 12.2-12.5 afr on the 175 shot. I have a aeromotive fpr on each of the fuel systems. I don’t care what base timing is. I set my timing at 36 deg at around 2400 rpm. Timing mark on the plug is dead center of the strap. View attachment 1715572251
Ya no more than 38 degrees or bad things will happen been there done that
 

71_dart_swinger

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A wide band a/f appears to be in my future. Nice set up btw...one of my all time favorite motors.
Here is one of my plugs after a few 100 shot blasts at about 5-12 seconds per run. Not sure what to look for. There are tiny orange speckles on the porcelain next to the electrode. Any input appreciated.
View attachment 1715573045
I’m blind in one eye and can’t see out of the other. Lol. Look for timing strap/mark on the electrode. Needs to be in the rounded arch of the electrode. Best place to start to be safe. Set total timing to say 34-35 deg tdc. If your running 100hp jets. Rule of thumb. Retard it 2 degrees per 50 hp. So in your case 4 degrees. Once you get a wideband. You can’t get it s little easier.
A wide band a/f appears to be in my future. Nice set up btw...one of my all time favorite motors.
Here is one of my plugs after a few 100 shot blasts at about 5-12 seconds per run. Not sure what to look for. There are tiny orange speckles on the porcelain next to the electrode. Any input appreciated.
View attachment 1715573045
First thing. Make sure plugs are tapped correctly. And in the right heat range. Go a step or two colder. Warm up your engine with your normal plugs. Once up to Operating temperature in for those plugs out and put in your nitrous plate then do one hit turn the engine off as soon as you can after the first hit and check plugs . A lot of the time although consistent it won’t run the exact same every time. Firm is the retard your timing 2° for every 50 hp ..100 Hp. retarded 4° Set your total Tammy to 34 or 35° before top dead center at about 2425 2600 RPM that way all of your timing is in check the electrode strap after the first run you should see a tiny mark a thin little strap that goes across the electrode try to set your timing to where the mark strap is in the middle If the 90 degree bend. Take a few detailed pictures of plugs from a few different angles. Need to see down in the plug for fueling Rich or lean conditions . Set you plug gap to 35.
 

360moparjunkie

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I have purchased an Innovate PSN-1 a/f gauge. It has a nitrous shut off feature when the system reads a lean condition.
I look forward to posting new better pics of the sparkplug after a pass.

Thank you to all sharing your knowledge.
 

Brooks James

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Hello FABO its been a while. My Dart is back on the road!!

Looking for technical advise on retarding my timing for 100 shot plate system. My engine, while freshly machined, has enough run time imo to introduce spray. Would like to know where the safe zone is.

My set up:
73 swinger @ 3,240# w/o me in it
Calvert 90/10 up front, tubular A arms, Adj strut rods
8-3/4" spool w/ 4:56 gears & 275/60 M/T ET Street SS tires
Slapper bars to modded steel gussets w/ welded frame connectors
727 & Hughes 4,000 rpm stall
.030 360 w/ kb107's standard stroke @ 10.7 comp w about 40 hrs run time
rhs heads from brian @ imm (2.02 stain valves, bee hive springs, bowl work..how he sets em up)
prw 1.6 stainless roller rockers
.600" valve lift int/exh dur @ .006 295 int & 307 exh w/ 108 lobe sep. set @ 2* advanced
billet cam gear double roller chain w/ v6 tensioner installed
TTI 1-5/8-1-3/4" step headers to dual 3" exhaust w/ dynomax super turbos
Weiand x-celerator 7545 open pl intake
Elelbrock 750 cfm carb running 100 octane low lead fuel
Plate system N2O....I have nozzles for 75, 100 & 140 shots
msd 6al ignition
msd pro billet distributor w/ 36* all in

I believe timing should be 30* to maybe 32*@ full advance for 100 shot to be safe. PLEASE ADVISE FABO as I do not want to damage what is a sweet running little power plant.

Motive:
I have an old acquaintance w a 06 gto 6.0 trick flow heads, cam, stall, big throttle body, 3:73 & sticky tires who looks to run my dart. His car weighs 3,725# vs my 3,240# He claims he makes 500hp. Just seeing his car run looks faster than mine i must admit. I think i need the juice to have a shot to run on his level.

thx in advance for all your input!
The general rule is 2 degrees of retard per 50 hp
 
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