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vacuum.

Brunoboy

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Apr 25, 2008
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San Bruno,CA Home of SFO
I know I have an idle surge, my rpms go between 800-1100 every so often, so far i have clamped everything down tightly , and i should do a BLT asap, but right now I have no compressor to pump air. Timing is on the dot, But I realized I am running dummy rich. I have Evo 560, 2g maf, Jons fmic kit, DSM Gt Highflow, Evo IX Pump, B16g running 12lbs. and a 2g dsm hard intake pipe,2g o2 housing, 2.5-3" straight pipe. CAS was put in as told, but had to adjust a bit to get it to run right. vacuum at 800 rpm is 10-12, 1100 rpm is 14-15HG, Idk. All my lines are hooked up as well.
-shane
 

Muskrat

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Jun 13, 2004
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Location
Lexington, KY
Quote:
vacuum at 800 rpm is 10-12



Well there's your problem, and you already know it. Solve this before trying to get more advice.
 

Brunoboy

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yha ok, well also the car SOUNDS like it has cams but it doesnt, its just a JDM 6bolt....(atleast I think its the same as the usdm right?). and Easiest way to find a vacuum leak? any advice?
-shane
 

4thStroke

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Oct 22, 2007
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Vancouver, WA
Since a BLT is out of the question right now, start it up and spray carb cleaner in the bay wherever a gasket may have blown out, where the vacuum lines connect, around the TB, etc. If the idle changes when you spray a certain area, you have found your leak.

Good luck.
 

Brunoboy

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i just replaced all Gaskets and seals on this motor. and I tried doing this trick the other day, but the idle doesnt change anywhere.
-shane
 

Muskrat

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Quote:
Since a BLT is out of the question right now



It's not. There's plenty of ways to do it without owning a compressor:

1) Take it to a shop that has air and ask to use it. Chances are one shop you go to will be nice enough to let you.

2) Go to a gas station w/ free air, or hell, pay the $1 or whatever it is now-a-day.

3) Find a friend of co-worker who has a compressor.

That's three options, just off the top of my head.
 

Brunoboy

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so bring the blt with me to a gas station? then take off my intake there,and put it back on after? lol I guess.
-shane
 

Brunoboy

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yha ill do it tonight
 

1947 was acting similar shortly after I bought her. Performed all leakage test's, still no sign of leaks or improovement's. After a couple days of scratching our heads, we noticed that the damn idle screw on the intake was missing completely. /ubbthreads/images/graemlins/dunno.gif Still haven't figured out where it went.
Anyway, replaced the screw, used" vfaq" to set it, plugged it, and viola! Idle surge fixed.
Maybee you'll get lucky like I did and it be that easy. Good luck
 

Brunoboy

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I can unscrew the bias screw all the way out but I can't seem to pull it out, anyone know a way to do this?
 

How are you compensating for the 560's at idle? Do you have a logger to look at the fueltrims?
 

Brunoboy

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San Bruno,CA Home of SFO
I was told that the 2g maf somewhat counters it, at first I thought I might be flooding and that's why it's being funky, I do have a logger and a safc hooked up, please tell me what I'm looking for. Thanks
-Shane
 

At idle the 2G MAS puts out almost the same Hz signal as a 1G, but your EVO injectors are flowing 30% more fuel than the stockers, so you will be VERY rich at idle. Don't believe what everyone on Tuners tells you.
For years many guys have gotten away with 550's and a 2G MAS, but its just not the same thing with the EVO 560's. Not only do they flow quite a bit more than 550's, typically 585cc or more, but they have LESS deadtime than the factory injectors, which means they inject >30% more fuel at idle. Most 550cc injectors have 180uS more deadtime than stock injectors, which means they flow less fuel at idle than the EVO's.
You could try removing the lower honeycomb, which should help lean out the idle quite a bit. But, the *right* thing to do is get a chip that matches your MAS and injectors, because the other thing the 2G MAS is doing is throwing you way off the timing maps. The 1G maps are already very aggressive, so more timing just means more knock issues.
 

Brunoboy

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Apr 25, 2008
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I bought that chip from one BluFalcon in the FS section. He said it was one of your chips, that he got from someone else on the board, he said it was for a 2g maf, and Evo injectors. "Shane,
I bought this a few years back from another member on the board from his GVR-4.

Here's the info I got from Keydiver about the chip off his message board:

8500 main rev limiter
6500 NLTS
Selectable Stutterbox
Knocksum gauge
EVO 560cc injectors
stock 2G MAS
2X Karman to log double Hz

Since it's a stage 3 chip, it'll have all the stuff that he usually adds to his chips like, octane reset, fuel cut removal and the usual stuff from stages 1-2. More info about what's included in each stage can be found on his site: www.dsmchips.com " thats what he said, so im waiting for it to come in, i think it should be here tmrw. Thanks , If anything I will contact you asap.
-shane
 

Brunoboy

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correct, i havent received it yet, hopefully today.
-shane
 

Brunoboy

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Apr 25, 2008
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Location
San Bruno,CA Home of SFO
this is the one I have now installed into my ecu
 
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