Trouble with boost over 1bar

topgear

The Thrillseeker.
Jun 4, 2007
80
0
0
Tallinn
When I reach 1bar of boost, it's like hitting a fuel cut or revlimiter.
The rpm arrow begins to randomly jump from 3000-7000 rpm,
or sometimes at full throtlle hitting 1 bar of boost and 4000rpm in second gear tacho stops @ 4000 rpm mark and speed slowly keeps on rising with a huge loss of power.
If I set max boost to 0.8 bar, nothing wrong happens, everything is smooth and fine.
Almost everything connected with ignition is changed, but still no results.
Engine 7m-gte `91
Manual tranny
AEM standalone
manual boost controller
 

buldozr

New Member
Jan 9, 2007
362
0
0
North Texas
Shytheed Dumas said:
1 bar = 14.5 psi = fuel cut, methinks.

He said "AEM Standalone", so scratch that, have you replaced the fuelpump and have you done the 12v hotwire wiring to the pump???? Please describe your fuel mods. Its hard to tell what the car is doing just reading but can you be a little bit more descriptive of what the car is doing? It sounds like ignition if your tach is going crazy. Check to make sure when you put the AEM in that a crimp or something didnt come loose.
 

topgear

The Thrillseeker.
Jun 4, 2007
80
0
0
Tallinn
modifications:

ARP Pro Series Head Bolts
Clevite Main & Rod Bearings
Wiseco Pistons & Rings - 7MGTE - 84mm Bore, .040 Oversize, 9.0 Comp Ratio
Eagle H Beams 4340 Forged Chromoly Steel Connecting Rods
Fidanza Built To Fly Flywheel
RPS Bronze Stage 5 Clutch Kit (Sprung Disk)
Titan Motorsports Head Gasket (Stopper style), 2.0mm
Toga High Volume Oil Pump
//Powerhouse Stainless Exhaust Manifold
Garret GT40
40mm UnKnown Wastegate
Custom Cooler & Piping
Spearco Intake
Custom 3` Exhaust
PIT Blow off Valve and Flange
Walbro 255lph Fuel Pump
WR Adjustable Fuel Pressure Regulator
RC Engineering 1000cc Injectors
Tein Super Street Suspension
Stop Tech break Pads
AEM

I`m shure that the problem is with the ignition
but don`t know where:1zhelp:
When I`m hitting 1bar mark I can see black smoke

255lph pump replaced stock one and nothing more
AEM works fine but still the tacho receives data from the it.
 

figgie

Supramania Contributor
Mar 30, 2005
5,225
16
38
51
Twin Cities, Minnesot-ah
I see all that but no wideband.

Black smoke is indicative of an EXTREMLY rich condition.

you can check the spark plugs to see if you are indeed running rich.
 

buldozr

New Member
Jan 9, 2007
362
0
0
North Texas
also, once you get wideband, make sure your using copper sparkplugs and also make sure the gap is around the .028 range. If you dont want to spring for the wideband, go to a dyno shop and have them tune it for you, its pricey though. Good luck brother and nice mods.

ohh yeah, make sure you did the j-tube delete and check fuel pressure. And those injectors are bloody huge! (overkill rules!) Sounds like you need a good tune. Also, Please look up "fuel pump hotwire mod", that will make tuning and driveability easier and predictable.
 

topgear

The Thrillseeker.
Jun 4, 2007
80
0
0
Tallinn
most interesting part of all this tuning adventure
is that I was told to change the ignitor in the dyno shop

there are so many different sparks I tried but still no result
ignitor, sparks, spark wires and many more have been replaced
but still 374,4 rwhp @ 4100rpm & 1.1bar of boost (red line 7500rpm)
I`m shure that there is not enough electricity power to fire up mixture in the cylinders

btw, wtf is copper sparkplugs ?
 

buldozr

New Member
Jan 9, 2007
362
0
0
North Texas
topgear said:
most interesting part of all this tuning adventure
is that I was told to change the ignitor in the dyno shop

there are so many different sparks I tried but still no result
ignitor, sparks, spark wires and many more have been replaced
but still 374,4 rwhp @ 4100rpm & 1.1bar of boost (red line 7500rpm)
I`m shure that there is not enough electricity power to fire up mixture in the cylinders

btw, wtf is copper sparkplugs ?

copper is usually the cheap ass sparkplugs. Most people running high boost go ahead and replace plugs every oil change or every other oil change. NGK's, densos and autolites are usually the norm. check to make sure you get the right heat range as well, do a search on sparkplugs here to find out what the norm is on 400ish horse 7m's and what they run. Make sure the gaps are uber close or you will just blow out the spark. Like mentioned earlier, .028 is the norm on the gap. Good luck man. Ohh yeah, check your timing too, you may want to back it off 2 degrees from stock. Make sure you run premium fuel for your street tune. If it is still giving you hell, you may have to find someone on the boards to help you out.
 

starscream5000

Senior VIP Member
Aug 23, 2006
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Wait, wait. You've got all that shit in your car and you don't know what a copper spark plug is??? WTF? You're asking for serious trouble without an upgraded valve train when setting redline to 7500 RPM's. I see no mention of any valvetrain mods. Your fuel pump will running out of flow before those injectors will. Why in the hell did you put 1000cc injectors in there?? What are your power goals?? You are going to have one helluva time getting any kind of decent tune with those big ass injectors...
 

buldozr

New Member
Jan 9, 2007
362
0
0
North Texas
do you have the dyno sheets(better have wideband results)? Im with starscream on that one. Those injectors need to go back to the rx7 you took them from. (just giving you crap dude) Those injectors should be good to atleast 700hp but you are trying to tune them for 450ish?? That sounds like a tuning nightmare(and no wideband or egt's to go off of). You probably would reconsider buying a wideband before you post a "forsale, blew the F***er up" thread.
 
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ValgeKotkas

Supramania Contributor
Apr 14, 2006
2,224
0
36
36
Over the pond
starscream5000 said:
Wait, wait. You've got all that shit in your car and you don't know what a copper spark plug is??? WTF?

Pssst... he's not a native speaker of English, so he just might not understand what you are talking about ;)
 

buldozr

New Member
Jan 9, 2007
362
0
0
North Texas
ohh yeah, that turbo sounds a little big for your goals bud. Lag must be stupid ridiculous, I dont think that turbo is even in its efficiency range(where is that smart guy that loves to post compressor maps when you need him???) It sounds like your setup is good for BIG POWER, your trying to tune for street and expecting good results(no bueno), I already made that mistake by building my mustang, I hate that car with a passion, I hate to drive it on the street. Notice the for sale on my sig. You need someone that knows 7m's to help you out dude.
 

starscream5000

Senior VIP Member
Aug 23, 2006
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If his turbo is a regular GT40, then he's right in the sweet spot on the compressor map at 1 bar at 6500 RPMs, even moreso at 7500. It it's a GT40r, then he's definitely not in the best efficient spot for that turbo.
 

topgear

The Thrillseeker.
Jun 4, 2007
80
0
0
Tallinn
What I`m trying to do is to get magik 500rwhp
not more not less
gt40 is really huge
@ 1st gear I`m having no boost at all
@ 2gear begins to rise

today I`ve tryed platinum sparks still nothing
now running on ngk r a little bit better but still crap

tomorrow I`ll try to get & post dyno results
 

starscream5000

Senior VIP Member
Aug 23, 2006
6,359
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Hot and Humid, KY
You need smaller injectors man. Try 580's or 680's. You also need to lower your rev limit until you instal some heavier duty valvetrain components or you will break something, or float the shit out of the stock valves.