Car unhappy w/ Thrasher. Ideas?

[EFFNQWKWE4]

My car is just not happy with my Thrasher chip! I think it's because i haven't changed the fuel pump yet? My setup is very basic, stock stuff, mostly. The FPR is set at about 43 with the hose off. Boost is set at about 15psi, but even at 12 with the Thrasher, the car leans out and stumbles when I gas it. Very weird. The car runs great with the factory chip, runs good with the ATR chip, but with alot of knock, but it just doesn't like the Thrasher for some reason. Part throttle acceleration is one stumble after another, and full throttle is just silly amounts of knock. The chip is a 92 octane one for stock injectors & I'm running 94 octane(sometimes 93, but never lower than that). Any ideas why this chip won't work for me? Just about every person on the board sings songs about Thrasher chips, and I was really looking forward to using it. For now though it's back in the holder, replaced by the stocker 'till I can figure out what's up. Any ideas would be a great help. Thanks in advance, guys!

 

[Ormand]

Two Things..

First, you need a scan tool, and before that, you need to make sure you're getting enough fuel. Stock pump was marginal at the original pressure, and will have even less margin when you turn up the pressure to go with a Thrasher. Running lean can get expensive, in a hurry.

 

[RobR]

Not running enough fuel pressure for one, you need 45psi. That's what its designed for, no less.

That should help a lot. And changing the fuel pump would be a help also.

 

[Black Car]

IMO, there are some cars that just don't like the Thrasher chip, peroid. No matter what I did to my 87 GN it wouldn't run exactly right on the Thrasher 93 or 100 chip. I could put the same chip in my other 87 and it would run fine. Didn't make any sense to me so I just accepted it.

 

[Scott231]

The problem is (at least) twofold:

1. A 16 or 17 year old fuel pump, and
2. a collapsed fuel sock on the end of the pump
3. and that's just for starters....
   [/list=1]
   
   And the proper fuel presure (as has been mentioned) wouldn't hurt. Helps to RTFM.

 

[motorhead]

Originally posted by Scott231
The problem is (at least) twofold:

1. A 16 or 17 year old fuel pump, and
2. a collapsed fuel sock on the end of the pump
3. and that's just for starters....
   [/list=1]
   
   And the proper fuel presure (as has been mentioned) wouldn't hurt. Helps to RTFM.

1. 
   
   Yep, go fix/update your fuel system.

 

[Taffy]

Originally posted by Scott231

Helps to RTFM.

That is what I like about Scott. ERIC.

 

[TurboDave]

I wouldn't jump on the bad fuel delivery problem band wagon so quickly!
After all, read his post carefully. The car runs just great with the stock chip.

His fuel pressure is 43#, only 2 down from what Thrasher recommends. A difference of 2# isn't going to cause all the nasty stuff he's describing.

I've been seeing a rather nasty trend developing here over the last year or so, having to do with VERY problematic chips (of all types, not just Thrashers).

There are a LOT more people out there burning chips for themselves and others, and I think this might be the root cause of many of these problems. I'm in the middle of investigating one such incident now, and will see when I get the chips in hand.

I believe it's a burner related problem, because I suffered from the same problems years ago when I was getting into the chip burning craze.

I, like I suspect many have, bought a cheap, easy to use prom burner. While it worked pretty good, it started making really wierd burns.
Everything would look perfect. No problems indicated by the burner, the image inside the chip looked perfect, etc.
Put the chip in the car and everything went in the toilet! The car wouldn't run worth and darn, stumbles, coughs, knock, etc, etc, etc.

Once I got my hands on a good burner (data I/O 29B, no longer available), I"ve never had a bad burn, and it immediately notifies me when I put a questionable chip in

Just something to think about guys.
When one chip works perfectly and another runs like doodoo, well....

 

[v8rob]

Thrasher chips

my '87 GN has the same problems with the Thrasher chips. I've purhased more than one and they all do the same thing. I've spent many hours trying to diagnose the problem without success. All the other chips I've tried work fine.

That having been said, I have to give credit where credit is due - Scott Simpson spent considerable time compiling emails to me in an attempt to diagnose/correct the problems with my car. He was very patient and did his best to help. I don't blame him for the problems.

I've spoken to several other local guys who have experience with the Thrasher chips. Most people seem to like them, but one guy said he also had the same problems. That guy is a very experienced tuner/racer. It doesn't make sense, but it really does seem like some cars just don't "like" the Thrashers. My car is a very late build so I don't know if that could have anything to do with it (possibly a variation in the ECM??).

I don't know what else to tell ya.

Rob

 

[Razor]

Trying to diagnose a problem without data is like walking with a blindfold.

On of the essential tools you should own with these cars is a scan tool to display some data..a bunch are on the market.

Also would be a FP guage with an extra long hose so you can tape it to your winshield and watch the fuel pressure as the boost climbs.

I've had a bad fuel pressure regulator hose cuase similar problems. Bad plugs..bad wires..bad gas..bad PCV..bad valve springs..blown headgaskets..the motor has to be mechanically sound..before the chip is to blame.

Story from an old time garage mechanic.." i've fixed more carburator problems by replacing plugs than carburators"

I'm glad these cars didnt come with Holley's..

Find someone with a direct scan and record some runs..go back and look at all the sensors for clues..

 

[v8rob]

Razor,

I'm not sure if your reply was a response to my post or the original post in this thread. As for me, like I said in my post, all the other chips I've tried and use on a regular basis work fine. I have an early ATR chip and an old Hypertech chip and even they work fine. They don't work as well as my newer chips, but they work better than the Thrashers. My newer chips work great. While I do not have a laptop, I do have a ScanMaster installed and I've made many, many runs watching various parameters on the SM. Everything looks fine with the other chips. With the Thrashers, I hit the 5 lb boost stumble and my O2 mV drop to almost nothing. This simply doesn't happen with *any* other chip.

I'm not trying to cause problems with any vendors, but I am stating my observations.

Rob

 

[Razor]

Nah man..not at ya..

I have experienced weirdness swapping/programming between chips myself. Perfect example are IAC's..you figure that you dont touch anything in the engine compartment..install a different chip..look at the IAC numbers..one reads 20 the other 50

You could of had a bad chip..who knows..Static can damage a chip...usually Thrashers run real well...as a generic can run.

I probably have the fastest car on the planet with a 92 thrasher chip..sig below...dunno..

 

[bruce]

Originally posted by TurboDave

I believe it's a burner related problem, because I suffered from the same problems years ago when I was getting into the chip burning craze.

I, like I suspect many have, bought a cheap, easy to use prom burner. While it worked pretty good, it started making really wierd burns.

I had a few chips act weird, and it was from some window apps running in the back ground. The 2732 are a rather slow chip to burn, and if something else is running in the background, that accesses the drive, bingo junk chip.
If your not using a designated machine for chip burning my suggestion is using Contrl-Alt-delete to close out everything other then explorer.

And more and more of the 32s have been written and reerased numerous times now.

 

[Larry Smith]

Hello all,
The original post stated that F/P is set at 43lbs. Thrashers will not work correctly with any thing less than 45lbs. I speak from experience. I experimented with fuel pressures trying to get my Thrashers (93 & 100) to perform as good as my very old Hypertec 3.
My experience is this: On a basically stock car, more timing with less boost is faster than less timing with more boost. So for example, if your comparing a high timing chip to a low timing chip the high timing chip will make the car faster, to the point of detonation. One final example. My car with thrasher 100 @ 22 lbs of boost ran 12.85 @ 107. My car with Hypertec 3 @ 20 lbs boost, ran 12.55 @ 107. The difference? more timing, less boost. Again I'm talking stock turbo, injectors etc.
Best regards,
Larry

 

[Razor]

Larry yes and no..see the HP you made was the same..107 mph. I bet your 60 foot was better on your 12.55 run wasnt it.

Yes timing will make your car faster assuming it doesnt detonate..

And final correction..there is more power to be had with boost than timing.Lb per degree..Look at it this way..if timing were true..nobody would run 35PSI through theyre motor. If your can tolerate the timing, great..usually there comes a time where you max your stuff out. And less timing more boost usually is more tolerated than the inverse.

I ran 12.18 at 110 on stock turbo and injectors 93 oct with alky. 1.69 60 foot

 

[Larry Smith]

Razor,
Good points, and a good discussion. I guess I should have said quicker, not faster. My 60ft was quicker on the 12.5 runs, but only by .01 -.02 average. What I did notice is that my shifts came quicker with the higher timing chip (especially 2nd to 3rd shift) On the first couple of runs with the Thrasher 100, I was questioning if my trans was working correctly, but when I changed back to the higher timing chip all was good again. I took that to mean that the car was accelerating faster. I agree that once you are into larger turbos more boost is the way to go, but my turbo is just blowing hot air at levels higher than 22lbs. My testing was done with 100 octane and I couldn't get more than 20 lbs out of the high timing chip without reaching the max out point. So for my car anyway, it was still quicker (on 100 octane) with the higher timing chip.
P.S. 107 mph is with a non-lockup convertor. I assume about 109 with a lockup.
P.P.S. 12.18 on stock stuff is pretty impressive!
Best regards,
Larry