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Old 12-15-2009, 11:34 AM   #21
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Cool, I thought he had a 2554. I saw E85 was offered at a lot of stations in the area of FL I went to. It's very knock-resistant fuel, and eliminates the need for the complexities and potential hazards of WI.

yea I'm running the 2871 which should be fine. The highest I've seen my Iat's were 99* after a long highway pull in 85* weather. Keep in mind that my temp sensor is mounted before my WI nozzle.

As for E85, I can't say that I've seen ANY stations local to me that carry it.
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Old 12-15-2009, 11:41 AM   #22
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Was the piston eaten on the exhaust side?
HOw did the exhaust valve corresponding to that point in the piston look?

What happened there is that detonation eroded/melted the piston top, like it ate it. Too much advance can cause that type of detonation. Some motors that detonate slightly will do that, though usually they'll eat the head gasket first, like BMW motors.

When dyno tuning and doing just one pull, the piston tops don't get so hot.
On a track at WOT, the piston tops get very hot and the motor doesn't want as much timing.
If you run timing as tuned on a signle dyno pull, it will be too advanced.

According to Rebello, the way to avoid that is to do 3 quick dyno pulls 3x in a row. That will get the internals good and hot, simulating a long WOT run. Ideally the 2nd pull is a bit stronger than the first, and the 3rd is no weaker than the 2nd, or something like that. I don't know how to keep the intercooler exit temps the same though...
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Old 12-15-2009, 11:42 AM   #23
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That's kind of too bad; I saw several E85 stations coming down 75 and then on the FL T'pke. I say kind of too bad, because E85 is very bad for the taxpayers overall. However, you can use it in FI engines to make crazy power.

You will never get an accurate indicator of intake temp with WI because liquid will pool around the sensor.

If you're worried about the motor, the safest thing to do is to not tune it to rely on WI as its primary means for det resistance.
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Old 12-15-2009, 11:57 AM   #24
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If you're worried about the motor, the safest thing to do is to not tune it to rely on WI as its primary means for det resistance.
Yea, I hear ya. That's why I don't plan to add much timing come dyno day. But even with conservative timing, I can't run 25 psi without the WI. I guess it's just a risk I'll have to take.
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Old 12-15-2009, 11:58 AM   #25
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Have you tried mixing in fuel additives? Toluene or Xylene?
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Old 12-15-2009, 12:02 PM   #26
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Have you tried mixing in fuel additives? Toluene or Xylene?
No.....
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Old 12-15-2009, 12:12 PM   #27
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It's all in the tune. Most people that spend the money to have a motor built also spend the money to have someone that knows what they are doing create the tune. Anyone that's playing around themselves and adding timing on the street is asking for trouble. Also having a timing map that's locked or only allows for limited corrections is a recipe for a blown engine. That's the safety margin that you track guys really need start exploring. What most of us run for corrections on the street is too small for what you track guys need.
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Old 12-15-2009, 02:17 PM   #28
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Originally Posted by levnubhin View Post
yea I'm running the 2871 which should be fine. The highest I've seen my Iat's were 99* after a long highway pull in 85* weather. Keep in mind that my temp sensor is mounted before my WI nozzle.

As for E85, I can't say that I've seen ANY stations local to me that carry it.
i would put a simple flaot switch on the tank as well running to a light where you can see it. Thats all im using atm as well and it works while being unobtrusive.
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Old 12-15-2009, 02:20 PM   #29
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I guess you could say I blew my built motor, I morely unlucky than anything.

JE pistons, 83mm 9.0:1 CR, no wrist pin wire on one side in #4 = piston slapping :(
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some det happened on one of my tunes:
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I took pdextra's and paul's spark tables and mixed them together, listening for det thru a long tube. By the time I turned my MBC to 15psi it started to knock hard. Turns out I had metal shavings from tapping the oil pan and there was dirt from assembly.

top of the pistons didn't look too bad, though the cyclinder walls in #1 and #4 had some vertical scoring.
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The engine was great until it started to knock. Hell it was even fun before I installed the turbo. It was surprisingly fast N/A, lightened internals are nice for throttle response.

Morale of my story, if you buy a pre-assembled engine online without paperwork, disassemble it when you get and clean all the parts and make sure every part is there. Don't let your friends intall the oil pan 30 minutes before you have the drill and tap for the oil return



edit: after further investigation the rod end-caps were also put on backwards, causeing abnormal wear on the bearings, ******* the engine up even more.

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Old 12-15-2009, 02:21 PM   #30
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Old 12-15-2009, 02:37 PM   #31
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I'm going to run an led to the pump so that I know it turns on when I hit 10 psi,
I did this...and it's really great for peace of mind...as well as being able to tell exactly when you're spraying for tuning purpose.

It won't tell you if the pump is not actually coming on though, just that the relay clicked over, and also won't tell you if you're out of fluid, or don't have pressure in the line (like due to hose/connector failure).

I originally thought about a red LED, but decided that was alarmist and went with a calming color since it being on is a good thing. RadiosHack didn't have blue that day so I got a green that matches gauges. I would do a level switch in red though to get your attention.
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Old 12-15-2009, 02:56 PM   #32
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meh thats why i dont use relays just high capacity switches the led is fed from the same wire so either the motor completes the circiut and the light works or it doesnt and i know something is wrong.
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Old 12-15-2009, 03:08 PM   #33
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Dude the motor can draw current even though the nozzle isn't flowing. Not a very good failsafe at all.
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Old 12-15-2009, 03:37 PM   #34
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pretty much. You need a flow gauge, and sadly they aren't cheap.
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Old 12-15-2009, 03:40 PM   #35
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I'm working on a solution, sadly its probly another 6 months off.
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Old 12-15-2009, 03:42 PM   #36
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Has anyone ever measured line pressure? Is the spike when a nozzle clogs big enough to trigger a failsafe?
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Old 12-15-2009, 03:46 PM   #37
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Probably not (could be wrong), the pumps maintain the line pressure through a bypass valve. Ideally, for the pump, the pressure in the line will never go above that valves breaking pressure.
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Old 12-15-2009, 03:51 PM   #38
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I'm working on a solution, sadly its probly another 6 months off.
A new car?
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Old 12-15-2009, 04:04 PM   #39
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Has anyone ever measured line pressure? Is the spike when a nozzle clogs big enough to trigger a failsafe?
Yes, as long as the failsafe is configured properly this will work to a certain extent. I did quite a bit of testing on mine for not only a clogged nozzle, but also if the line burst. Both situations triggered the failsafe and it went to a different map and wastegate.

The one big thing that still worries me is that with a progressive system, there is still a window for error while using a flow sensor as a failsafe. A partially clogged nozzle most likely won't create a situation that will trigger the failsafe.
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Old 12-15-2009, 04:15 PM   #40
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The one big thing that still worries me is that with a progressive system, there is still a window for error while using a flow sensor as a failsafe. A partially clogged nozzle most likely won't create a situation that will trigger the failsafe.
In a dumb system I would say this is probably correct. In a fully programmable controller with a flow sensor accurate to +-5cc/min I think it could be easily detected.
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