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dankish1
12-16-2004, 03:28 AM
hey everyone i bought a 90 laser/eclipse off this site about 2 weeks ago, and when i run it on high boost 20p in 4th and 5th gear at 4500 rpm the car sutters like back and forward... im thinking that it might be the cv joints? also when i accelert really hard its pretty hard to keep the car straigt it likes to pull really hard and gets pretty sloppy... if anyone has any clue of what could be wrong with it please let me know... thnx alot
oh and this problem dose not occour with 8p of boost:confused:

Phuqu
12-16-2004, 08:17 AM
Fuel cut out? Are you supposed to run 20psi?

kevie88
12-16-2004, 09:15 AM
Wait a minute, what turbo are you running? stock?

I think I know why it's stuttering. Because it's going to blow up.

Go4Long
12-16-2004, 09:36 AM
first off...stop driving like an ass:P fifth gear at 4500 rpm would be like what 160-180? second off...could be fuel cut...could be compressor surge.
and accelerating hard and it being hard to keep straight is probably a straight up traction problem...just a thought.

JustinL
12-16-2004, 09:50 AM
The spark plugs may be improperly gapped. Start there, it's the easiest thing to check.

DSMer4Life
12-16-2004, 11:08 AM
Unless the car has some way of detering/delaying fuel cut, you're not going to be able to boost 20psi safely. Does the car have any sort of fuel control like an Apex-i S-AFC? Have you datalogged it to see what's happening? Running high boost without knowing how the engine is responding is asking for trouble. In the short term, turn the boost down to be safe. Notice there's no problems at 8psi?

Fuel cut is really your car's computer thinking it's getting too much air. This is partially due to the air sensor not being able to handle it (MAS overrun), as well as what the factory has set as a "safe" boost level. To deter fuel cut, you not only need more fuel to compensate for the additional air being pushed into the engine, but you also need to "trick" the stock computer into allowing you to run past factory settings. This can be accomplished by several methods (in ascending order of difficulty/cost):

Remove the lower honeycomb from your stock air sensor to allow more air through the unmetered section of the sensor, as well as backing out the plastic screw in the unmetered section. This will allow the sensor to flow a little more before fuel cut kicks in. It's relatively safe without any fuel modifications.

Upgrade to a second generation (+1995) air sensor which flows more, thus raising the level where fuel cut will occur. You'll want bigger injectors and some sort of fuel control (S-AFC) with this.

Get a modified EPROM chip for you computer that eliminates fuel cut. You better know what you're doing with this choice, because you're basically removing the only method the car's computer has of saving your engine if things go wrong. Monitoring and datalogging are crucial.

If you are new to turbo Lasers/Talons/Eclipses (aka DSMs) I think you should check out a few links before doing any mods:

http://ca.dsm.org/
http://www.vfaq.com/FAQlocator-index.html

Oh, and your steering problem is called torque steer. 90-91 lasers were only produced as FWD models. FWD with +200HP will yank your steering wheel around a bit!:D You can get third gear rubber if you really want to. The only thing to do is firm up the front suspension. A strut bar, polyurethane sway bar/control arm/engine mount bushings, stiffer springs and performance struts will help. Take 'er easy.

JeremyD
12-16-2004, 11:48 AM
Is it this one?

http://forums.beyond.ca/showthread.php?s=&threadid=62678

The 16G should be able to run 20psi without cratering. However like mentioned earlier you are probably hitting fuel cut and will need some fuel management system to actually use that. It looks like you have the injectors you need and the fuel pump. Unless there is a fault in one of those.

Where are you able to hit 5500 RPM in 5th right now? that is crazy.

dankish1
12-16-2004, 02:04 PM
http://forums.beyond.ca/showthread.php?s=&threadid=62678

ya this is the car... and i wasnt toattly driving like an ass i was on a highway out of the city trying to see what its like with the high boost... the high boost is set at 18psi and low is 8psi.. im new to turbo cars all toghter and this was my first time pumping up the boost since i bought the car because i didtn want to drive it that fast in the city.. but ya if anyone has any other info that might help me please let me know... and thaks alot to all the people that have responded with great information
chris

2.0turbo
12-16-2004, 08:35 PM
I have never heard of a BLAHA modified airflow meter but I would guess that it is desined to eliminate or delay fuel cut. The boost amount at 20 is ok as long as you have good gas. Keep an eye on your knock counts and try to keep them under 7 or 8.

When the steering wheel is ripped from you hands it is called torque steer. Having a similar set up, I am all to familiar with this and although it is really fun sometimes, other times it sucks. The transaxle will send power to the wheel that is spinning and the only way to eliminate this is a LSD. The other option is to put an all wheel drive system in. Both cost money and will destroy your tranny alot faster. Just hold on really tight make sure that you aren't right beside someone when your turbo hits full boost.

As for the shutter, get used to stupid problems that are next to impossible to locate. Dude, you have a DSM and modified at that.

Toms-SC
12-16-2004, 08:48 PM
Easy, you need more boost to overcome the friction caused by the air