my gn is breaking up in high rpm at 20psi

[teddie87gn]

if any one has any suggestions please help. i just dumped an a** load of money and parts into my car and the thing runs slower than it did when it was closer to stock. the car runs fine until i put my foot into it. around 20psi and above the car is breaking and losing power the engine "SEEMS" to be miss fireing but i really can't tell if it is fuel or ignition related. this is really frustrating for me. the car is falling on it's face at the track and it's really embarassing. one other thing i have a brand new trans in my car and it seems to have a very quick shift from 2nd to 3rd is there something wrong with this as well. any help would be greatly appriciated. thank you everyone.

 

[KEVINS]

How are the valve springs? Normally stock ones give out right at 20psi but maybe your aftermarket springs are a bit week You may want to have one checked just for giggles.. Have ya tried new plugs? Any scan tool data?

ks

 

[teddie87gn]

i've got brand new valve spring and my scan tool data seem to be ok but i haven't looked into it really deep yet

 

[Quick89]

Breaking up

Try a narrower spark plug gap .30-.32

 

[teddie87gn]

kevins
howin the hell are you going so fast on a stock turbo i've got a stage 4 turbo frt mount pte inter cooler and a ton of other parts and i can't get below a 12.80 time. WHAT AM I DOING WRONG

 

[Louie L.]

You should look at your scan data closely and provide us with some numbers. Specially WOT numbers. What you describe could be valve springs, fuel pump,ignition or just plain old spark knock.

using race gas?


let us know.

 

[teddie87gn]

yea i'm useing race fuel 112 octane and at wide open i'm not getting any knock and o2 are reading at about 780 to 805 mV
the vavle springs are brand new from poston i got them to match the gn110 cam i put in they are suppose to be high perf. springs to match the cam.

 

[blackbuick87]

How about some info about what you were running BEFORE you put all this money into the car. If it was not running right before it will have the same problems now.

I think it is ignition. Try regapping and look at wires, module and coil pack. Does heat seem to have a factor in this, i.e. does it run fine for 10 miles and then act up?

 

[Intercooler]

Originally posted by teddie87gn
kevins
howin the hell are you going so fast on a stock turbo i've got a stage 4 turbo frt mount pte inter cooler and a ton of other parts and i can't get below a 12.80 time. WHAT AM I DOING WRONG

Many have done it on stock components including me. If you have the fuel I would turn to the ignition system. Put on new wires, module, coil pack and gap the plugs at .032" and see how it is. O2 is fairly new? That combo should be 11's no problem.

 

[KEVINS]

I noticed that you have listed a 7th and 8th injector.. Are you using any of them? You shouldn't be.. What chip do you have and what is the chip timing at? Check plug wires, electrical connection to the coil pack. Clean the connections and use electrical grease on the connector.
What were you running before the mods?

It may be a mismatch in parts, too big of cam and turbo for the small amount of boost which obviously is a problem? I don't know what power band the cam likes or the turbo but the larger plenums and TB can/will slow down the boost velocity which can slow down the car a bit. IMO, I'd get rid of the TB/plenum and put the stocker back on. A 62mm is more than large enough. Once you get it to run clean above 20psi she'll come around!

FYI, I am hoping to break into the 11's the next time out with new chip timing..

ks

 

[teddie87gn]

kevins if you get a stock turbo into the 11 you are my hero

 

[KEVINS]

Originally posted by teddie87gn
kevins if you get a stock turbo into the 11 you are my hero

LOL... I'm not the only one who's done it... I already have 2 friends that have done it and there are many others on here that have also. It just takes some determination to not give up on the stock combo. I find myself wanting the next "speed part" a lot but I know I don't need it..

Once you get the misfire figured out then you'll be in the 11's. Give us the info requested above and stick with it and it'll get there.

ks

 

[cutt]

20psi

i had the same problem once,it was the chip.i was using a kenne-bell hot flash and could not run a lot of boost try turning the boost down a notch or changing chips, you may need a chip with less timing in it to run high boost.

 

[Intercooler]

Re: 20psi

Originally posted by cutt
i had the same problem once,it was the chip.i was using a kenne-bell hot flash and could not run a lot of boost try turning the boost down a notch or changing chips, you may need a chip with less timing in it to run high boost.

You know that could be true. We don't know what chip and DC he is getting so that could throw everything out the window but his O2's seem okay.

 

[teddie87gn]

the car did run good before all the mods but of coarse like most people i though more and bigger would be better. well since the up grades the car doesn't seem to pull as hard. and it just recently has developed this high rpm studder and the car just doesn't feel the same. it very discouraging. before the car would run 12.50 all day on street tires with 1.8 60 ft times. now i've been useing slicks expecting better et's wrong my 60 have gotten down to 1.5 but my times are way off my average is now 13.00 i did get a 12.8 once but the car still did not feel right. next run was in the 13 again and i did everthing the same but the hightrpm studder was there.i am useing both aux injectors and i don't know which chip i have exactly i bought it used off a wrecked turbo regal with the inj and turbo i have now too. i want a max effort chip i just don't have the money for it right now.

 

[KEVINS]

1. You NEED the chip programmed for YOUR combo.. period.
2. I doubt you need the aux injectors with 40's unless you are running mid 11's or faster.. I don't know what hp/mph they give out..

You get these variables taken care of and you will prolly take care of all your problems.. Chips are very cheap $25 on up. There is no excuse not to get one or two..

ks

 

[teddie87gn]

where in the world can i get a chips for 25.00!

 

[KEVINS]

http://www.thrasherchips.com/

Only One of the popular chips being used on this BB, so others will chime in..

ks

 

[teddie87gn]

i checked out the site. how do i know which one to get. and what do they mean by the terms studder 2300 and static

 

[TT/Ameasap]

Im happy with my thrasher I paid $25 for mine and turned boost up bigtime.0.0kr! And I got anti-theft.

I get so boost gitty

But seriously, get a chip burned for your combo in the future, it should help out a good bit.

HTH
Bo