looking to get the timebomb faster down the track...

[OMG_WTF]

hello all.. ok, i will try and keep this short b/c i tend to be longwinded..

i have been daily driving what would seem to be the worst/best scenario for blowing up an 07..

07 STi.. relevant mods:

k&n typhoon intake
aps turbo inlet
txs 4" catless downpipe (uncapped)
agency 1lb crank pulley
phenolic insulating manifold gaskets

no tune... no other mods..

right now i will say, tune, duh! DUH! of course.. but i do not have money for hardware and outlaw drags are tommorrow.. in a month hopefully i will have $$$ for a UTEC but until then, this is whats up.. im also just plain interested to know why the car acts the way it does..

as of now, my best time is 13.32 @ 103 w/ 1.79 60ft.. best mph is 105.. best 60 ft is 1.74..

i would like to point out that i am a total noob at drag racing.. ive literally never dragged another car besides my STi.. ive been to the track about 4 different times.. got prolly 25-30 runs on my car.. ive realized after last drags that my shifting has been utterly horrid up to that point and ive since worked on my technique.. i honestly feel like i can shave a have second just be not granny shifting..

anyways, back to the car.. so, 1st and second gear have no problems.. 3rd is where bag things happen.. when running thru the gears, if i granny shift 2nd-3rd, in 3rd at 5900 rpm the car will stall for a have second and throw CEL P0244, along with P0137 and P2096 at some point.. from this point im going to refer to P0244 as "overboost".. when i hit overboost, the car stalls for what seems like half a second before resuming acceleration..

edit: as far as i can tell, the overboost action is not dependent on the actual boost pressure.. ive seen the boost gauge holding steady around 20 psi or more.. usually boost is at like 17psi when the overboost error happens..

it has never overboosted 1st or 2nd.. in third (if i keep the throttle floored), it will hesitate briefly at 5900 (always at 5900) and then finish out the gear with no problems.. keep in mind this is coming out of 2nd and into third.. also if i downshift to 3rd and floor it immediately, it will overboost at 5900.. but, if i downshift into 3rd and hold the throttle so the car remains steady 4900 rpm @ 60 mph, then floor it and hold, it pulls very hard all the way to redline..

just like 2nd to 3rd, if i granny shift 3rd to 4th, 4th is not as strong.. and then it will overboost at 5900.. and sometimes 2 or even 3 more times before hitting redline.. but if i downshift to 4th, hold steady at 90mph, then floor it, it will not overboost..

more interesting things.. in both 3rd and 4th it overboosts easier and more often when going uphill (more load?).. and less going down.. but 5th doesnt seem to overboost, but 6th does???


i am running stock rims and tires (potenzas).. on the street i run like 35-37 psi all around.. on the day i pulled the 1.74 60 ft, i had let some air out of the tires but i cant remember exactly how much.. last weekend i let out too much i think.. they were like 21 psi all around and i could get lower than 1.81 60ft.. what is the ideal pressure for drag racing???

what is the best engine speed to come out of the hole at..? when i ran the 1.71 and what i usually do is just floor it, let it bounce off the limiter than drop it as fast as i can (horrible? lol).. as i said, last weekend i couldnt get lower than 1.81 60fts but im not sure if it was strictly b/c of the tire pressure..

and finally, what if the best position for the DCCD? ive heard many people say auto is best.. but in the manual is says lock forward is best for acceleration.. thoughts?

thanks very much in advance for any and all advice.. and sorry for any headaches caused by my retardedness..

in any case, the races are still tommorrow and i will report back if my new shifting technique had any effect on my times..

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[sperry7]

Use Enginuity and pick up a map online for your car FO FREE.

Auto is the best setting.

If you are cutting 1.7-1.8 60 fts your launch is pretty solid. Ideally you don't want to be spinning your tires so whatever PSI you need to set your tires at to get the job done, do it. It will depend on track conditions though.

Overboosting happens because your wastegate is not passing enough exhaust gas. You can remove your turbo and port the wastegate to help alleviate the problem, but there are no guarantees. Having a more restrictive exhaust can help. ie put a high flow cat in there.

Your Air/fuel ratio is probably pretty bad so you should get a tune pronto.

[07BlueWRX]

Originally Posted by sperry7

Use Enginuity and pick up a map online for your car FO FREE.

Auto is the best setting.

If you are cutting 1.7-1.8 60 fts your launch is pretty solid. Ideally you don't want to be spinning your tires so whatever PSI you need to set your tires at to get the job done, do it. It will depend on track conditions though.

Overboosting happens because your wastegate is not passing enough exhaust gas. You can remove your turbo and port the wastegate to help alleviate the problem, but there are no guarantees. Having a more restrictive exhaust can help. ie put a high flow cat in there.

Your Air/fuel ratio is probably pretty bad so you should get a tune pronto.

+1, You need to port the wastegate on the turbo to alleviate said over boost code. Or you can get it tuned out. Either way though if you don't add EM you are going to hurt stuff. But probably not as bad as you already are at the track.

Anyway you dice it if you keep your habits up than you wont have this STI for very much longer. But who am I to tell you how to drive your car. I just hope you got the resources to get yourself out of the hole that you are potentially digging

EDIT: I just read the part about the Redline Clutch drops At the track they spray a chemical compound on the track manufactured by a company named VHT. It increases grip for the tires maximizing the effectiveness of a proper launch. The problem with your AWD STI is all that power to the ground, with the extra traction, and the high engine revs. Literally is destroying your driveline every time. Good times though, Like I said before though, Hope you got coin

[PowerTrip]

Before you do any porting, you need to get a tune. I'm yet to see an '07 STI that needed the wastegate ported. Remember VF43 = larger wastegate than the VF39 that only need to be ported some times. Most good tuners can alleviate any boost spiking issues through the tune or by switching out the restrictor pill. Good luck.

[07BlueWRX]

oh yeah. Forgot they switched to the 43, read about this on the 39 all the time.

[STimo]

haha, trying not to be long winded didnt work obviously .. BTW if you cant afford a simple tune, what are you going to do when your motor blows up?? because running your car the way you do it is bound to happen, and honestly im surprised it hasnt happened already after hearing about all the horror stories with the 07's.. If you overboost and throw a code, WHY WOULD YOU KEEP IT FLOORED SO IT KEEPS OVERBOOSTING?!?!?!? It amazes me that people can be so stupid.. I could understand if you had the funds to just fix it if it breaks, but you obviously dont so what are you gfonna do when your motor blows?? You obviously arent too smart. Good luck, you're going to need it..

[NSFW]

mods + no tune = dubious
mods + no tune + ECU going into panic mode + racing = dangerous

[OMG_WTF]

thanks for the supremely helpful post.. seriously, reading comprehension is your friend..

edit: to STimo

obviously the cars not running too horrible if i managed to pull the same times as gabedude with his custom tune or w/e...

[rxer311]

Well the drags are today, i guess we will hear tonight about the motor letting go after it throws every code in the book. Just because your car is running fast doesn't mean your car is running happy...

[4ST-AIR]

Originally Posted by PowerTrip

Before you do any porting, you need to get a tune. I'm yet to see an '07 STI that needed the wastegate ported. Remember VF43 = larger wastegate than the VF39 that only need to be ported some times. Most good tuners can alleviate any boost spiking issues through the tune or by switching out the restrictor pill. Good luck.

+1 on that VF43 WG issue was corrected over the VF39

[4ST-AIR]

Originally Posted by rxer311

Well the drags are today, i guess we will hear tonight about the motor letting go after it throws every code in the book. Just because your car is running fast doesn't mean your car is running happy...

+2
For each of the 07 STI motors I blew. And I NEVER made it to the track. I think anyone running traps with any type of mods and not protuned is asking for trouble IMO. Throwing CELS and still going to the track your going to blow those pistions or crack a ringland.

[4ST-AIR]

Originally Posted by OMG_WTF

thanks for the supremely helpful post.. seriously, reading comprehension is your friend..

edit: to STimo

obviously the cars not running too horrible if i managed to pull the same times as gabedude with his custom tune or w/e...

The obvious difference is next week gabe will be at the track and you'll be watching him from the stands. Things can go from fine to WTF in about 2 seconds and your car is telling you it is going to go WTF. I never tossed a cell on either engine your being given a chance here. If you make through tonite your just looking at the next time. If your goal is to blow the engine your spot on tack then.

[302@12psi]

You're car will more then likely blow up shortly. Get a compression test done and pay attention to the numbers on piston #4.

I'm sure if Gabe wanted to build a map that's unsafe and would really push the car you "bolt" ons with no EM STI wouldnt stand a chance.

Not trying to be a jerk but your arguement/throught process has some major flaws. If you cant afford EM you shouldnt put the mods on until you do. You have no power train warranty will will more then likely blow the motor (just about every 07 with no EM or a catless DP with Cobb I've seen is shot).

Enjoy your day at the races.

[4ST-AIR]

Originally Posted by STimo

haha, trying not to be long winded didnt work obviously .. BTW if you cant afford a simple tune, what are you going to do when your motor blows up?? because running your car the way you do it is bound to happen, and honestly im surprised it hasnt happened already after hearing about all the horror stories with the 07's.. If you overboost and throw a code, WHY WOULD YOU KEEP IT FLOORED SO IT KEEPS OVERBOOSTING?!?!?!? It amazes me that people can be so stupid.. I could understand if you had the funds to just fix it if it breaks, but you obviously dont so what are you gfonna do when your motor blows?? You obviously arent too smart. Good luck, you're going to need it..

LMAO for some reason it makes more sense when I see you post it to someone else I guess it's not as personal in someone elses thread when I read it You just lay down the facts hardcore I guess why beat around the bush.

+1 STimo

[STimo]

Originally Posted by 4ST-AIR

LMAO for some reason it makes more sense when I see you post it to someone else I guess it's not as personal in someone elses thread when I read it You just lay down the facts hardcore I guess why beat around the bush.

+1 STimo

Yeah sometimes im a bit blunt, i'll admit it.. But people ask for advice and sometimes they dont like to hear the truth.. I just lay it down how it is, the OP asks why his car is acting the way it does and it's because the car doesnt like the way its running, that's why it's throwing codes left and right and hitting fuel cut.. Honestly it doesnt take a genius to figure out somethings wrong when you're WOT and all a sudden the car immediately stops pulling for a couple seconds and throws a CEL when you're still WOT.. Anybody that keeps it WOT after an event like that is asking for it.. Especially when knowledgeable people tell you your motor is gonna blow, but you insist on still going to the track the way it's running.. I honestly dont understand it, if you cant even afford a used EM that costs ~300 bucks, how in the hell are you gonna afford a new shortblock?? Possibly longblock?

[4ST-AIR]

I hate to say this but I think do to the lack of response from the OP I think he is at the track.

And you thought I was not listening to the NASIOC advice hehehe. I do have respect STimo I guess it gets rough after going through this time after time. I'd like to say thank you for STimo's advice.

[gabedude]

His motor will blow in a few weeks unless he is at high altitude. He's gonna run out of fuel and get too many lean missfires (and pre-ignition), the ringlands are gonna go south.

BTW. That was my one and only run in super high humidity at 67 degrees out. The next day it was 55 and dry. I woulda ran a high 12 at 105 on a Stage 1 tune alone. Hell, if I just had one more go at it, I coulda been at 13.0@104 or perhaps 12.9@105 that night. All I woulda needed was a better 60 ft, and a faster shift from 2nd to 3rd.

[OMG_WTF]

ok so you guys were right.. it blew up...




siiiiiiiiiiike! headed to the track right now

[ExpO]

You don't have money to pay for a tune....

What makes you think you'll have money to buy a new shortblock when you blow your ringlands or spin a bearing and the dealer tells you to piss off?

[STimo]

Originally Posted by OMG_WTF

ok so you guys were right.. it blew up...




siiiiiiiiiiike! headed to the track right now

LOL.. you had me for a second.

[4ST-AIR]

Originally Posted by OMG_WTF

ok so you guys were right.. it blew up...

siiiiiiiiiiike! headed to the track right now

He might not have alot of money but maybe parents do. No responsible adult would knowingly go to the track when they know they are going to blow the engine. I guess it pisses you off to see someone do this to such a nice car.

Either that or he got the car fixed already and is just jackin us around.

[squashman]

Most anticipated "pics of post-trackday carnage" thread? Quite possibly

OP, enjoy running super lean at full boost with a high flow exhaust until the stock tuned ECU dumps fuel

[misterwaterfallin]

so what happened?

[4ST-AIR]

Originally Posted by misterwaterfallin

so what happened?

Well if I had to guess 1 of 2 things

1) Ran so bad ashamed to post

2) Ran so good the engine blew

Don't you think with the attitude of the posts he would have come back and made another remark.

[OMG_WTF]

Originally Posted by 4ST-AIR

"Ran so good the engine blew

LMAO

so should i be ashamed of 13.32 @ 103? or 13.34 @ 105? or sub 1.8 60fts... from what ive seen this is consitent with stage 2 07s... i sincerely hope it goes 12.5 or better after i get it tuned..

lol.. you guys are mean.. outlaws got rained out last night.. i was like 4 cars back from running when the rain hit.. very disappointing..

for some reason i like to be an against the grain type of guys but i think the reason im not too worried is that ive been running the car for 4 months and nothing has happened..

the only thing ive changed in the last 3 months was the aps inlet that i had sitting around that i finally put in last week..

also, while i dont have extra cash for programming hardware, just rest assured the car wouldnt be down for long if the motor blew..

car and insurance paid for by yours truly, btw.. all $935 a month worth