Thrasher doesn't like my setup

[Larry Smith]

Been running around for many years with a Hypertec stage 3 chip. Max boost with 93 octane is 15 lbs without knock. I decided a few weeks ago to jump into the 21st century and bought a Thrasher 92. Drivability was much better and was able to run 17lbs of boost on 93 octane, but the car didn't seem any faster. ( I guessed, due to less timing in the Thrasher.) Soooo. I bought a 100 octane Thrasher. Now with 100 octane gas I can run 22 lbs of boost with no knock, but the car seems to quit pulling hard at about 4 grand and doesn't wake back up until right before the shift point in any gear. It's not missing or detonating, but just feels kind of lazy. Almost like it's running out of powerband. So I start wondering, is it shifting late? lazy MAF? fuel pressure falling off? etc. etc. Played around for a couple of days with fuel pressure etc. and couldn't find any problems. Finally, I put the Hypertec back in and the car came back to life and ran like I knew it should with 100 octane and 20 lbs of boost.
I'm not flaming the Thrasher cause for 25 bucks it's worth experimenting. I gotta believe it's a timing issue. Anyone else experienced anything similar? Is there really that much more timing in this "old school" chip? or is there something in my combo that the Thrasher doesn't like? I mean the difference is quite noticable.
All comments appreciated.
Larry

 

[geiman]

Believe it or not, what you may have is a problem with valve
springs, not a chip issue. Try changing them out and see if that
fixes the upper power band "laydown".

Geiman

 

[Larry Smith]

Geiman,
Thanks for the reply.
I thought of that too, except that with the old chip the car regained the urgent feel and fairly leaps to 5 grand and snaps the shifts perfectly. I have heard that for a stock engine combo (turbo injectors, heads) that more timing less boost is preferable to the other way around. My experience seems to be proving it. I did have to turn the boost down 2 lbs. to 20 with the Hypertec to get 0 knock, but it's quicker @ 20 lbs than it was at 22 with the Thrasher. My o2 readings were a little high with the Thrasher 790-800, but if I turned the FP down the idle went to hell.
Anyone know what timing the Thrasher has? Does anyone remember what the Hypertec 3 has? How about the loose convertor? could that be playing a role somehow?
thanks again,
Larry

 

[gnturbo]

I am having the very same experience with a thrasher92 and a 13 year old Kenne Bell chip.The thrasher was good but the Kenne bell chip was a madman.Spools quick and hauls a@@.My knock was easily tuned with boost and fuel pressure adjustments.Maybe old school wasnt as old as some might think.?humm makes you wonder....

 

[tim87tr]

Instructions for the Thrasher say that they are set up to run on 45 to 47 lb fp static for the optimum injector spray pattern. I did not see where you mentioned fp setting, just the O2s, which seemed in range. It says to increase boost if fp is at 45 lb static and the O2s are still too high with no kr, not to lower fp below 45 lb.

My car ran about 770s O2s on 45 lb fp, 20 to 21 lb boost, Torco 110, and no kr with the Thrasher 100. I have had good luck with the chip and have only ran my Turbo T three times in the last year since buying it.

 

[nastysix]

I tried raising the boost but started getting knock above 22 lbs. Raising the FP to 46-47lbs static made no difference and lowering it to 43-44 made the idle rough which I expected it would. I played around with it for quite a while before giving up. It was a good excuse to do a early "spring cleaning." It actually felt rich although the o2's didn't show it. All parimeters actually looked pretty good on the scanmaster.
I am pretty convinced at this point that it is a spark advance thing. The older chips certainly had a bunch, and have gotten a bad name because of it. But tuned correctly and with good gas, they still work pretty good, at least for me.
Thanks for the replies,
Larry

 

[gnturbo]

well I did it again,I decided to try the thrasher 92 chip out again,out came the kenne bell and in went the thrasher.Set my fp to 45 and then started her up,let her idle for about 20 seconds and shut her down ,restarted her and went to check the iac.It was way off,like 80.So I started to adjust it and itwould not go down.I screwed it all the way in and got it down to 50 at idle,then it threw my tps way out.I tried to adjut it and did.By this time the car is making my eyes water from all the gas coming outta my tail pipe.My o2s were low,my blm and int were at 128 and never changed even when driving the car.I drove it around and man it spools so slow,not very exciting at all.No rush just blah.I mean the turbo spooled up to 17 psi but no thrill.I drove it and tuned it for the rest of the day and it never got any better,little knock here and there nothing but .5-1.5.That was enough,I pulled over ,shut her down and put the kenne bell back in,Set fp to 44 ,boost to 15psi ,reset my iac with no prob the 15 at idle,30 in drive at idle,Tps back to .42 at idle,away I went burning rubber at the top of first on into second gear,No knock until about the end of 3rd got a 1.7 which I tuned out by raising the fp to 45psi.Now I am running the balls off the car ,grinng from ear to ear and the thrasher is back in the glove box again and I am looking for a 5.0 to hurt his feelings.....other than that the thrashers anti-theft feature is nice.

 

[Razor]

Thrashers are an open loop chip at idle and WOT..

First is ...has the ecm been diconnected at the battery when chips have been swapped..next..a chip wont cure any driveability prob's a car has..

And all these tests appear to be seat of the pants..so..a thrasher 92 has about 20 degrees timing..a 100 has about 23 degrees and a 108 has about 27 degrees..the lower timing tables are te same on all chips what changes are the WOT lv8 and MAF tables ..in other words WOT.

As far as IAC adjustments...do them with a scan tool and tweak them just a bit a little at a time..trying to constantly change them while the car is idling will get you no where quickly.

I've run all kinds of chips..and they all respond differently..and remember the ECM has to be given a chance to relearn itself..

So when ya put it in and start the car it will run like crap till the ecm relearns it self..

Julio

 

[5litereater]

open dump

Steve
Opening the dump should not hurt the 60' times unless it's spooling up quicker and causing a loss of traction. I don't run Thrashers but I race with an open dump on a regular basis with a high 11, low 12 GN and get 1.6 60's often. All my recorded data is with dump open so I can't compare data for you. Bottom line: open dump should help 60' times if anything.