high boost top end miss?
10-05-2005, 07:47 PM
#21
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I would give denso iridium plugs a try. We have run tons of street/race turbo stuff to 30psi and the only plugs that would last and not miss at big boost were the denso iridium's. NGK also has an iridium plug but not sure it is quite as good. The cross for the NGK TR6 is an IT20. I would also try to gap them in the low 20's because you have so much cylinder pressure, and even more with nitrous.
Hope this may help
Hope this may help
10-06-2005, 02:06 PM
#22
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Spark blowout won't be relative to what type of PCM you are running. All of them (stocker, and standalones) use either ground pulse or 5v signal to trigger whatever power transistors you run (also called ignition modules, ignitors, and a few other names), and those in turn charge and fire the coil...
My thoughts on this issue are that it's a fueling problem with MS. Jim's MAP signal goes up and down wildly at full boost, such that the pulsewidths/duty cycles are also all over the place. Only at high boost. Other megasquirters runnign high boost have seen this problem, most of them "dampen" the MAP sensor signal either physically or electrically.
Jim, we have a few options we can try. But looking at other cars' datalogs compared to yours, you definitely have a TON of pulsing/fluctuation in the map signal only at high boost/load (204 - 220KPA within 1/6 of a second, repeated up and down), compared to the other cars running similar boost...
-scott
My thoughts on this issue are that it's a fueling problem with MS. Jim's MAP signal goes up and down wildly at full boost, such that the pulsewidths/duty cycles are also all over the place. Only at high boost. Other megasquirters runnign high boost have seen this problem, most of them "dampen" the MAP sensor signal either physically or electrically.
Jim, we have a few options we can try. But looking at other cars' datalogs compared to yours, you definitely have a TON of pulsing/fluctuation in the map signal only at high boost/load (204 - 220KPA within 1/6 of a second, repeated up and down), compared to the other cars running similar boost...
-scott
10-06-2005, 02:25 PM
#23
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I would increase the dwell time of the coils, we've (speed inc, me) have already have missing problems and ignition problems, and now we run the BS3. Think about the load placed on that setup pushing a 4000 lb setup down the track.
10-06-2005, 05:33 PM
#24
Originally Posted by Pro Stock John
I would increase the dwell time of the coils, we've (speed inc, me) have already have missing problems and ignition problems, and now we run the BS3. Think about the load placed on that setup pushing a 4000 lb setup down the track.
ok, first thing is try some diferent plugs and dampen the map source. i will also turn back on my missfire detection up top and see if it points to problem. if that doesn't help then we will switch over to mega running my ignition and adjust the dwell up.
if that doesn't work then i will be back looking for more advice.
10-06-2005, 09:00 PM
#25
FormerVendor
Originally Posted by parish8
4000? i wish, try an even 5000lb
ok, first thing is try some diferent plugs and dampen the map source. i will also turn back on my missfire detection up top and see if it points to problem. if that doesn't help then we will switch over to mega running my ignition and adjust the dwell up.
if that doesn't work then i will be back looking for more advice.
ok, first thing is try some diferent plugs and dampen the map source. i will also turn back on my missfire detection up top and see if it points to problem. if that doesn't help then we will switch over to mega running my ignition and adjust the dwell up.
if that doesn't work then i will be back looking for more advice.
10-06-2005, 10:18 PM
#28
Originally Posted by Paulz2820
jim here is a silly question but are your spark plugs indexed correctly?
the plugs i am about to put in there are autolightracing plugs with a cliped ground strap. i wouldn't think it would matter much with a cliped ground.
10-06-2005, 10:51 PM
#31
this is the first i have heard of it. i would like to know if kurt from w2w or harlan take the time to index their plugs or any of the other high hp guys.
what direction do you want them pointing? how do you make them point that direction?
what direction do you want them pointing? how do you make them point that direction?
10-06-2005, 11:34 PM
#33
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Originally Posted by parish8
this is the first i have heard of it. i would like to know if kurt from w2w or harlan take the time to index their plugs or any of the other high hp guys.
what direction do you want them pointing? how do you make them point that direction?
what direction do you want them pointing? how do you make them point that direction?
10-07-2005, 07:19 AM
#34
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We only index plugs that have dome's that can come in contact with the plug. We just check our plug gap to verify its between .025-.028 and install them.
Kurt
Kurt
Originally Posted by parish8
this is the first i have heard of it. i would like to know if kurt from w2w or harlan take the time to index their plugs or any of the other high hp guys.
what direction do you want them pointing? how do you make them point that direction?
what direction do you want them pointing? how do you make them point that direction?
10-07-2005, 09:04 AM
#35
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Originally Posted by GoldRust
Don't think that indexing plugs makes a difference for this application. I do not index wormboys plugs and I belive that we are somewhat above the horsepower that you are making. Oh, and don't listen to the ngk iridium suggestion. For one if you ran a plug that hot you wouldn't make it to the 330' mark before you had plug material going through the exhaust side of your turbo. The fast system also has enough nutz to drive the coils and ignition system. The e-dist would not be my first choice but it definatly works. Sounds like you should take intmd8's advice to start off with. You could also look into getting some of the msd coils
FAST told us we have to use the "EDIST" system - which is nothing more than an overpriced clone of the Ford "EDIS" system, which I've installed on a TON of cars. The EDIS coilpacks, however, are very hot sparking - guys are running them on 30+psi of boost at 7500+RPM with no problems in other applications.
-scott
10-07-2005, 09:33 AM
#37
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I had ignition problems with my FAST/eDist combination around 730rwhp. I needed to increase the dwell time of the coils, and Lance Ward's suggestion (guy @ FAST) was that I buy $1200 worth of MSD ignition stuff. So I sold my FAST for very cheap and bought a BS3. No more ignition issues. Can't argue with a setup that can use stock truck coils and power a door slammer into the 6's.
10-08-2005, 09:41 AM
#38
indexing your plugs is done by putting a line with white out or something matching up to your strap so you can see where it is once its in the hole. this can be adjusted by using shims. when your looking for the last hp you want the strap facing down towards the piston. that way once the compression occurs it can only blow the spark back to the strap instead of off into nothingness. i can understand W2W making it to not have PtoV issues.
Last edited by Paulz2820; 10-08-2005 at 12:11 PM.
