shane661
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posted March 01, 2007 06:01 AM
 Edited By: shane661 on 1 Mar 2007 06:02
Methods of Advancing/Retarding Timing
I was wondering about manual advancers (such as sold by Muzzy's). If you use one of those, can you still retard the timing with an external box, like the Schnitz, for nitrous use?
I'm wondering if I should buy the pc-usb ignition module, or not. I have seen reports that the timing advancer, and rev-extend features may have problems?
In short, what is the best way to advance/retard timing for reliabilty and performance?
  
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dougmeyer
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posted March 01, 2007 06:21 AM
Just keep in mind that an adjustable trigger rotor moves the entire advance curve forward or back, not just portions of it. Although effective, it's not as good as a PC3R for tuning ignition timing, as you can't change the curve.
Doug
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H2 to ZX12
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posted March 01, 2007 06:35 AM
is it polically correct to time retards? 
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entropy
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posted March 01, 2007 09:25 AM
quote:
is it polically correct to time retards?
routinely done at national and local events; we just don't say the "R" word anymore.
Well, my wife calls me retarded, but i guess she's entitled.
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ridgeracer
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posted March 01, 2007 11:16 AM
Something else to take into consideration is that what you are messing with is not just an ignition trigger but really a crank position sensor. When you fake it out you are not only delaying or advancing your ignition but when the injector starts to spray fuel (not how long it sprays).
Did the engineers design the injectors to fire at some set crank/cam/intake valve position that optimizes fuel atomization? If so what effect does spraying + or - 10 degrees have?
Maybe the effect is negligable or offset by the increase in power.
Something to consider.
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Y2KZX12R
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posted March 01, 2007 11:58 AM
Injector timing offset is a varriable on some FI setups such as Motec and GM computers. On the LS-1/6 engines with large cams, changing injector offset can help stabilize idle issues.
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dougmeyer
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posted March 01, 2007 04:13 PM
FI Timing
That was a concern at Muzzys when we first did the adj. triggers, but we never found that the 4 or 5 deg change (max) effected A/F (=torque) to any consequence.
Back in the day on the Lucas timed mechanical injection we used on the 500 inch BB Chevy Can Am engines, we could move the injector squirt +- 90 degrees and did so to cure specific tuning issues at certain tracks, eg., more grunt off the corners or a need for a certain mid -range improvement.
How many degrees do you have to slew it on an LS1/6 to get an effect, Y2?
Doug
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Y2KZX12R
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posted March 01, 2007 05:10 PM
I havent changed the injector timing on my car and didnt play with that at all on the dyno. I'm just running 8# boost and its my daily driver with a stock cam. But I was talking to (forgot his name) http://www.eastsideperformance.net about injector timing in HP tuners when we did the power enrichment (WOT) tuning on the dyno. I dont remember discussing any specifics on it other than its one tool for idle quality with big cams among other varriables.
Doug, are you using HP Tuners on that Vette? I highly recomend it, its un real what it has to offer. Hand helds are a joke and even EFI Live or LS-1 Edit cant compare.
Injector scaling is so simple a caveman can do it. 
No need for a vacuum referenced FMU with a blower.
Wanna re-calibrate a modified MAF meter? A snap with data loging and MS Excel.
I've had the idea of using a GM 4 cyl ECU for the 12r for years. Just no time to do it.
Is that Vette stock? Dont worry, you can tell me if its not, I wont tell anyone.
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supra5677
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posted March 01, 2007 06:05 PM
ridge racer is correct.. after my ecu mod my bike runs lean..also I get 40mpg crusing at 90 mph. As a net effect I don't think tricking the ecu to get an extra 640rpms is a good thing. Also there are way more ignition values in the actual ecu than in the powercommander. Also the power commander makes 1 general map.
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H2 to ZX12
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posted March 01, 2007 06:56 PM
quote:
quote:
is it polically correct to time retards?
routinely done at national and local events; we just don't say the "R" word anymore.
Well, my wife calls me retarded, but i guess she's entitled.
what are wives for? 
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dougmeyer
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posted March 02, 2007 09:40 AM
Y2,
LS-1 Edit, LG Longtubes w/short cats, stock Ti mufflers, Halltech TRAP, 32 lb injectors
'Bout 395 rwhp
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supra5677
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posted March 02, 2007 10:01 AM
wow!!
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Y2KZX12R
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posted March 02, 2007 12:09 PM
quote:
Y2,
LS-1 Edit, LG Longtubes w/short cats, stock Ti mufflers, Halltech TRAP, 32 lb injectors
'Bout 395 rwhp
Nice power for N/A.
I'm going to change the exhaust this spring. I'm pushing 435 rwhp (530 crank) thru a completely un touched exhaust. Iron manifolds and factory flattened 2" y pipe.
With a set of long tube headers, a good y pipe It should pick up at least 40 hp.
I'll end up breaking the stock rear end at that point. I've allready replaced all the bearings twice but the carrier is getting sloppy now. The drag radials hook hard and are doing a number on the rearend.
At least the 4L60e is holding up so far. Of course i'm pulling 20 degrees of timing out during the 1-2 and 2-3 shifts hoping that the tranny and rear will last a while. I can see a T-56 and 12 bolt rear in my future soon thou.
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dougmeyer
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posted March 02, 2007 02:20 PM
Edited By: dougmeyer on 2 Mar 2007 14:21
Cam next for me( as soon as I sell some motorcycle parts !) LGX3 or an MS3, haven't decided on which yet. Either is good for about 35 hp on an LS-6. My goal is 435+ at the wheels (It's a nostalgia thing- I always wanted a 435.) Like your car, any more than that and the clutch goes. Replace that and next the rear end breaks, fix that and then the input shaft or tranny turns to shrapnel.
Why is that so easy to accept and understand when working on a hot rod car, and when you run into the same concept on a bike all you get is massive whining about how "weak" everything is. Always amazes me.......
Doug
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Gunner
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posted March 02, 2007 03:23 PM
Doug..................You need one of these to cure that problem and then a call to Mark Williams for the drive shaft issue
That clutch deal can be handled by any of a number of folks..
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dougmeyer
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posted March 02, 2007 03:54 PM
Oh trust me, I know which parts to buy. Won't need the above until I start running the 98% 
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Y2KZX12R
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posted March 02, 2007 04:02 PM
Yea I really need to change the cam too. And an electric cutout at the y pipe.
Who am I kidding. My wife cant believe I havent taken the engine out of the camaro yet. "geezzz, youve had that car 2 years now and havent even taken the engine out once yet...." I get my balls broken a lot about my HP addiction. The wife thinks I need counciling, so i'm buying a 5 axis cnc to port my ls-1 heads with.
Need your heads done?
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shane661
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posted March 02, 2007 04:05 PM
I think I've been threadjacked, severely. I will assume I should just give the dynojet ignition module a go....
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dougmeyer
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posted March 02, 2007 04:47 PM
Oh, yeah. Sorry, I thought we said that a while back.. Get a PC3R USB
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Gunner
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posted March 02, 2007 07:22 PM
quote:
Oh, yeah. Sorry, I thought we said that a while back.. Get a PC3R USB
Doug........................There's NO SUCH thing as a PC3R USB There is a PC3R or PC3USB but not combined... oops 
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muleskinner
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posted March 02, 2007 11:51 PM
TIMING ADVANCE
I'm just going to put my quick opinion in here. I took my Muzzy's adjustable ignition advance rotor out of my 12, as the bike did not feel like it ran as strong after I installed the rotor at five degrees advanced.
My thoughts were the ECU picked up the advance and retarded the timing to compensate. Maybe I'm wrong, but the bike would no longer pick up the front wheel in first and second gear from a five MPH roll. ??? After reinstalling the stock rotor the bike now picks up the front wheel in first and second gears again. Go figure.
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dougmeyer
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posted March 03, 2007 08:20 PM
It didn't compensate. It was just the wrong thing to do- too much advance.
Yest I guess all the USB 's have the "R's" capability don't they.
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shane661
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posted March 04, 2007 12:59 AM
Actually, the usb model alone doesn't allow any timing adjustments. You have to purchase a separate ignition module for that feature.
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GUNNER
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posted March 04, 2007 03:21 AM
quote:
Yest I guess all the USB 's have the "R's" capability don't they.
Doug..........That would be a BIG Negative
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