Spark blow-out causes
Thread Starter
Joined: Nov 2009
Posts: 1,621
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From: THORNTON, PA (NEAR PHILLY)
We'll guys...you were all mostly right-on regarding my mostly water-injected beast...w/the pump disabled the car seems to be pulling pretty darn hard w/o breaking up!!! This was with the current .027 gap. Only running about 11 psi right now for short bursts, so the water/meth probably aint even needed anyway. SOB is really a handfull around town even with the 275/60 MT DR's...they just have no chance once boost hits!
My IAT seems to be inaccurate or really slow b/c driving around on a 80* day today the IAT show about 95*...then it dips around peak boost a couple of degrees, then climbs after letting off a bit. Then dips down again before boost. Never really climbs. Either the ebay 31x12x3 IC is just awesome or the IAT sensor is just slow or faulty.
My IAT seems to be inaccurate or really slow b/c driving around on a 80* day today the IAT show about 95*...then it dips around peak boost a couple of degrees, then climbs after letting off a bit. Then dips down again before boost. Never really climbs. Either the ebay 31x12x3 IC is just awesome or the IAT sensor is just slow or faulty.
9 Second Club
Joined: Nov 2003
Posts: 13,616
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From: Norn Iron
What sort of sensor is it ? And where is it installed ?
Easy way to test is pull it out and point a hair dryer or something at it and see how fast it responds.
If it's slow at all, get rid of it and fit one that works.
Easy way to test is pull it out and point a hair dryer or something at it and see how fast it responds.
If it's slow at all, get rid of it and fit one that works.
Thread Starter
Joined: Nov 2009
Posts: 1,621
Likes: 31
From: THORNTON, PA (NEAR PHILLY)
Its a GM piece that threads in right before the throttle body near the alt pulley...I'll borrow my wifes hairdryer later...
I'm starting out at 84 deg and it climbs to 130 or so just past the 1/8 mile on 15 psi.
At 11 psi I was seeing 120 degrees at the end of the 1/4 mile. Same start temp.
IAT is about 10" from the TB
I have no idea what's too hot.....
Good that the non water runs work!
At 11 psi I was seeing 120 degrees at the end of the 1/4 mile. Same start temp.
IAT is about 10" from the TB
I have no idea what's too hot.....
Good that the non water runs work!
I'm on my 2nd IAT sensor, and this one is supposed to be a 'fast responding' unit, and I see very little change during a pull as well. Mine is mounted in the same location as well.
TECH Fanatic
Joined: Oct 2011
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We'll guys...you were all mostly right-on regarding my mostly water-injected beast...w/the pump disabled the car seems to be pulling pretty darn hard w/o breaking up!!! This was with the current .027 gap. Only running about 11 psi right now for short bursts, so the water/meth probably aint even needed anyway. SOB is really a handfull around town even with the 275/60 MT DR's...they just have no chance once boost hits!
My IAT seems to be inaccurate or really slow b/c driving around on a 80* day today the IAT show about 95*...then it dips around peak boost a couple of degrees, then climbs after letting off a bit. Then dips down again before boost. Never really climbs. Either the ebay 31x12x3 IC is just awesome or the IAT sensor is just slow or faulty.
My IAT seems to be inaccurate or really slow b/c driving around on a 80* day today the IAT show about 95*...then it dips around peak boost a couple of degrees, then climbs after letting off a bit. Then dips down again before boost. Never really climbs. Either the ebay 31x12x3 IC is just awesome or the IAT sensor is just slow or faulty.
Thread Starter
Joined: Nov 2009
Posts: 1,621
Likes: 31
From: THORNTON, PA (NEAR PHILLY)
It sure beats chasing your tail with all that other ****. lol I felt pretty confident it would run right without the WATER injection. Just glad you tried it before screwing with all that other crap and spending a bunch of money. Now if it breaks up now, before you do anything else, tighten the gap. If it doesn't leave it alone. Now get it to the track and let us know how that beast does.
, and yes I will tighten the gap if need be as I am a big fan of tighter gaps.I just want to get some more time around town to make sure it will all stay together. The next issue I need to work on is getting this POS to shift into 3rd gear under power...I'm at a loss with that at the moment, and may need to start ANOTHER thread on that
Thread Starter
Joined: Nov 2009
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From: THORNTON, PA (NEAR PHILLY)
And I put a hair dryer on the IAT and it shot to 160* pretty fast and then dropped fast also, so it looks like its working OK. I don't think I'm on the throttle long enough for the temps to shoot up that much. All the more reason not to run the meth/water inject I guess.
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Verdad Gallardo Thread Starter
Joined: Nov 2009
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From: THORNTON, PA (NEAR PHILLY)
Some follow-up questions...
Since this sucker runs so nice with 11psi and no meth, I am now wondering do I even need meth injection? I dont seem to be getting high IAT with these short-burst type blasts around here, and maybe on race day (which would be a complete rarity) I could run mostly race gas - whatever the highest octane they would have available at the track.
Just some thoughts...
Since this sucker runs so nice with 11psi and no meth, I am now wondering do I even need meth injection? I dont seem to be getting high IAT with these short-burst type blasts around here, and maybe on race day (which would be a complete rarity) I could run mostly race gas - whatever the highest octane they would have available at the track.
Just some thoughts...
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Some follow-up questions...
Since this sucker runs so nice with 11psi and no meth, I am now wondering do I even need meth injection? I dont seem to be getting high IAT with these short-burst type blasts around here, and maybe on race day (which would be a complete rarity) I could run mostly race gas - whatever the highest octane they would have available at the track.
Just some thoughts...
Since this sucker runs so nice with 11psi and no meth, I am now wondering do I even need meth injection? I dont seem to be getting high IAT with these short-burst type blasts around here, and maybe on race day (which would be a complete rarity) I could run mostly race gas - whatever the highest octane they would have available at the track.
Just some thoughts...
Thread Starter
Joined: Nov 2009
Posts: 1,621
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From: THORNTON, PA (NEAR PHILLY)
We'll things are going well. Engine runs great with 11-12psi and will destroy the 275/60/15 DRs pretty much in any gear. IATs seem pretty low w/o any water injection so I haven't been using it. When I bump the boost to 14 psi I'd like to reintroduce the injection especially for track days. What percentage of total fuel flow would you use for the water/meth inj? Think I'll get a case of Boost Juice for conveinience more than anything.
Boost juice is a good option. It's consistent, quality, and relatively inexpensive.
Here's some infor for figuring out injection volumes.... it's a good read.
http://howertonengineering.com/tech-...ating-jetting/
Here's some infor for figuring out injection volumes.... it's a good read.
http://howertonengineering.com/tech-...ating-jetting/
Thread Starter
Joined: Nov 2009
Posts: 1,621
Likes: 31
From: THORNTON, PA (NEAR PHILLY)
Boost juice is a good option. It's consistent, quality, and relatively inexpensive.
Here's some infor for figuring out injection volumes.... it's a good read.
http://howertonengineering.com/tech-...ating-jetting/
Here's some infor for figuring out injection volumes.... it's a good read.
http://howertonengineering.com/tech-...ating-jetting/
The article states a 50/50 mix should constitute about 15-20% of total fuel flow. Mine was set to 13% at max boost. Guess I can just leave the settings alone and run the proper water/meth fluid rather than windshield washer.
