In Soviet Russia car build YOU!
#242
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Smaller return than feed is an awesome way to get fuel pressure fluctuations at idle and low RPM which will wreak havoc on the driveability of the car. The return line needs to be the same size as the feed line. There is no reason to downsize it, and every reason not to.
Can you please explain why the smaller fuel return would cause fluctuations?
#243
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This is my guess:
Think of it as a garden hose with four even leaks in it. Those leaks are your "injectors", and the open end is the "return line". If you restrict the open end of the hose, more pressure goes through the leaks. If it's free flowing, they stay constant.
So, my guess is, under different fuel loads, the return line is sometimes a restriction, but sometimes it's not.
How wrong am I?
Think of it as a garden hose with four even leaks in it. Those leaks are your "injectors", and the open end is the "return line". If you restrict the open end of the hose, more pressure goes through the leaks. If it's free flowing, they stay constant.
So, my guess is, under different fuel loads, the return line is sometimes a restriction, but sometimes it's not.
How wrong am I?
#244
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This is my guess:
Think of it as a garden hose with four even leaks in it. Those leaks are your "injectors", and the open end is the "return line". If you restrict the open end of the hose, more pressure goes through the leaks. If it's free flowing, they stay constant.
So, my guess is, under different fuel loads, the return line is sometimes a restriction, but sometimes it's not.
How wrong am I?
Think of it as a garden hose with four even leaks in it. Those leaks are your "injectors", and the open end is the "return line". If you restrict the open end of the hose, more pressure goes through the leaks. If it's free flowing, they stay constant.
So, my guess is, under different fuel loads, the return line is sometimes a restriction, but sometimes it's not.
How wrong am I?
#246
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first track day was a success.
Shenandoah circuit is absolutely insane and I loved it. Nothing broke except YET ANOTHER COP. It started misfiring a little bit under load. I had a spare - swapped it in and everything was gravy.
Oil temp never went above 200-210F. 80F+ ambient. At about 10psi. I don't think that's normal....? But it's a pretty tight track.
![](http://farm9.staticflickr.com/8020/7230787062_df9884ad4e_k.jpg)
![](https://fbcdn-sphotos-a.akamaihd.net/hphotos-ak-ash4/460299_10150972892966823_739766822_11923038_1856867598_o.jpg?dl=1)
Brakes were good. Power was good. Tires were awesome.
Shenandoah circuit is absolutely insane and I loved it. Nothing broke except YET ANOTHER COP. It started misfiring a little bit under load. I had a spare - swapped it in and everything was gravy.
Oil temp never went above 200-210F. 80F+ ambient. At about 10psi. I don't think that's normal....? But it's a pretty tight track.
![](http://farm9.staticflickr.com/8020/7230787062_df9884ad4e_k.jpg)
![](https://fbcdn-sphotos-a.akamaihd.net/hphotos-ak-ash4/460299_10150972892966823_739766822_11923038_1856867598_o.jpg?dl=1)
Brakes were good. Power was good. Tires were awesome.
#249
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I will get you the part number for the ls2 coils I am using. Then go spend $150 at FM for their bracket and spark plug wires. It is well worth the money for the FM parts and makes things much cleaner.
Check my build thread later in the week for my new catch can setup. Hopefully it will be the last time I ever fuxor with it.
Check my build thread later in the week for my new catch can setup. Hopefully it will be the last time I ever fuxor with it.
#250
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Have you checked your spark output circuit? Could that somehow be damaging your COPs? I've never heard of them blowing so often. Once in a while, yes, but not like this. Surely if a new one blew every 1000 miles (has it even been that long?) People like Sav, myself, Hustler, and all the other turbo track junkies running them would be having issues.
#251
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Have you checked your spark output circuit? Could that somehow be damaging your COPs? I've never heard of them blowing so often. Once in a while, yes, but not like this. Surely if a new one blew every 1000 miles (has it even been that long?) People like Sav, myself, Hustler, and all the other turbo track junkies running them would be having issues.
#252
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I will get you the part number for the ls2 coils I am using. Then go spend $150 at FM for their bracket and spark plug wires. It is well worth the money for the FM parts and makes things much cleaner.
Check my build thread later in the week for my new catch can setup. Hopefully it will be the last time I ever fuxor with it.
Check my build thread later in the week for my new catch can setup. Hopefully it will be the last time I ever fuxor with it.
Have you checked your spark output circuit? Could that somehow be damaging your COPs? I've never heard of them blowing so often. Once in a while, yes, but not like this. Surely if a new one blew every 1000 miles (has it even been that long?) People like Sav, myself, Hustler, and all the other turbo track junkies running them would be having issues.
#253
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#255
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Soviet does not have VVT so that point does not matter to him. Also I could care less about "ballerest" ls coils. The ones that are good enough on a vette are more then good enough on the miata.
#256
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The ballerest coils aren't much more expenisve, anyways - http://www.ebay.com/itm/NEW-IGNITION...ht_3179wt_1396
And you can get 8 of them for $160
http://www.ebay.com/itm/New-Ignition...#ht_500wt_1396
I'm still probably going to go the junkyard route, because that's how I roll. Also with my COPs - only one coil genuinely died. Like, not firing at idle dead. The other two just started misfiring under load. I think more dwell could make them work. I have it set to 2.2ms in TunerStudio.
#259
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Vette makes aroud 60hp/L on more cylinders.
Soviet makes around 200hp/L on fewer cylinders.
That means there is WAY more fuel in soviets cylinder vs vette cylinder.
Hence, sovient needs more spark than a vette
#260
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I'm still probably going to go the junkyard route, because that's how I roll. Also with my COPs - only one coil genuinely died. Like, not firing at idle dead. The other two just started misfiring under load. I think more dwell could make them work. I have it set to 2.2ms in TunerStudio.
I have used both the truck ls coils and the ones from the vette. I have had less problems with the ones from the vette at up the 17psi.