why does my car die down in 3rd gear?

[Boosted97GS-T]

1st and 2nd gear is really strong, but when i hit 3rd it pulls hard at first then it feels like it kinda just levels out, its kinda hard to explain, its not just my butt-o-meter, cause i raced my buddies 97 cobra, and he jumped out about a car in first and i pulled up right beside him in second and stayed there but when i hit 3rd, it felt like the power just died down and the cobra just pulled away like nothing

 

[gstspyder1998]

Originally posted by Boosted97GS-T
1st and 2nd gear is really strong, but when i hit 3rd it pulls hard at first then it feels like it kinda just levels out, its kinda hard to explain, its not just my butt-o-meter, cause i raced my buddies 97 cobra, and he jumped out about a car in first and i pulled up right beside him in second and stayed there but when i hit 3rd, it felt like the power just died down and the cobra just pulled away like nothing

Mine does the samething. The strongest gears are 1st and 2nd for my car also then my car doesn't pull that hard anymore. I think that's just how it's geared for.

 

[Tevenor]

Its called a T25.

 

[gstspyder1998]

Originally posted by Tevenor
Its called a T25.

 

[TurboSpyder98]

hehe my car pulls like a bat out of hell in the first 4 gears... it is less in 3rd and 4th though, thats just gearing. i have a T25 and it doesnt really bog down in 3rd more than any other gear really.. but that does sound like it could be your problem. wait i just read your sig.. its probably heat soak from that T28 on the stock intercooler also that cobra has a much stronger top end than our cars.. but i bet if you get a fmic or a big ass smic it would help out immensely

 

[Boosted97GS-T]

i dont think its the gearing cause right when i shift into 3rd and the turbo hits full boost again, it sucks you into the seat but only for about 2secs. or so then it just levels off

btw, i do have a big28

 

[candela]

what are your boost gauge and egt gauges saying

 

[larryd]

actually he has a Big 28.. and the answer to your question is in yer mods list..

1) stock injectors
2) 2.5" exhaust instead of 3" exhaust
3) stock intercooler

Id replace them in that order .. what psi are you running?

 

[Boosted97GS-T]

Originally posted by larryd
actually he has a Big 28.. and the answer to your question is in yer mods list..

1) stock injectors
2) 2.5" exhaust instead of 3" exhaust
3) stock intercooler

Id replace them in that order .. what psi are you running?

thats kinda what i figured was maybe the problem, also i run 15psi, i really cant run anymore than that because of boost spike. I'm spiking to about 21psi then it settles at 15psi, so i'm also thinking that i'm just feeling the spike when i shift.

does anyone know for sure if a ported o2 housing would solve my boost spike problem?

 

[Boosted97GS-T]

also egts run 1500degrees, and my timing gets up to 21

Larryd, did you run your car with the stock injectors and the Big28? or did you do everything at one time?

 

[larryd]

i had my stock injectors and fuel pump in the first night I had the Big 28 and did the fuel work the next day.. I can tell you I was completely disapointed in the turbo before I did the fuel work, it felt no faster then my T25 did.. it held boost all the way to redline but it didnt feel fast..

a ported o2 housing should help you but you still may need a 3" back.. the one thing you may want to look into is the o2 eliminator pipe with a dump.. supposedly they help alot.. Id prolly get that now if I had the chance.. you interested in buying my TRE Ported O2 housing??

 

[Boosted97GS-T]

Originally posted by larryd
i had my stock injectors and fuel pump in the first night I had the Big 28 and did the fuel work the next day.. I can tell you I was completely disapointed in the turbo before I did the fuel work, it felt no faster then my T25 did.. it held boost all the way to redline but it didnt feel fast..

a ported o2 housing should help you but you still may need a 3" back.. the one thing you may want to look into is the o2 eliminator pipe with a dump.. supposedly they help alot.. Id prolly get that now if I had the chance.. you interested in buying my TRE Ported O2 housing??

well i guess i'll be getting me a afc and some 550's next week and see if that helps me out, also i think i may check for a boost leak or something, because i see no reason for me getting that much spike even with a 2 1/2" exhaust, i'm intrested in your O2 housing, email me with a price

 

[larryd]

the other thing is your prolly running pig rich right now.. I was rich as hell on my 550s so Im sure your rich on your 450s.. not as bad as me but you are and without fuel control you cant really trell.. what does your pocketlogger show your o2 voltage as, and whats your EGTs at WOT in 3rd..

 

[Boosted97GS-T]

1500 degrees and i'm running .94 volts

 

[larryd]

well thats a little rich.. Im not sure on the 1500 cuz its in F.. mine is C.. but definitely get the 550s and get the AFC and then lean it out and watch your o2s and egts and youll notice a nice difference.. id get the o2 ported first.. Ill email you as soon as I figure out what im doing

 

[Violater101]

I ran stock injectors and even sidemount for a couple of months and had no problems with boost spike (ran around 18psi). As to answer your question about 3rd gear. If you look at most dyno sheets, thats about when the stock cam's die and you will start to notice a considerable loss of HP. That's where upgrading your cam's come in. You might still see a 5hp drop off, but its still a net gain of say 40HP in 3rd gear....its as if you just discovered a new gear. This will definately help on the street/hwy pulls from 55mph :> I would say cams are good for 5ish MPH in the 1/4 mile times..anyone have any data to confirm this? Also, I was always under the assumption that you should be around .92V ideally for a 2G. As for your EGT's, 1500F is 815.5C, and thats okay. How rapidly are your EGT's climbing when you go WOT?
That is a good indicator of whether or not you pulling timing or not. If you have the DSM Link, you will no whenever timing is pulled over 5degrees because you will get a CEL. Many people don't realize that with an AFC and logger, you think "ahh yeah, 21+ timing), but in reality you are seeing 26-7 degrees of timing with 6 degrees of knock retard = bad. If you have the funds, i would definately recommend this vs an AFC. Are you running stock cat still?

 

[larryd]

unfortuantely there is no hard core info that says cams + big 28 = good..

 

[Violater101]

Well, I will be dyno'ing my car in the next few weeks and hooking it up to a wideband O2, so I will let you know how much HP I am loosing in 3rd gear. I know my 3rd gears doesn't pull nearly as hard as 2nd gear...dont' get me wrong, I'm still pulling, just not as hard.

 

[larryd]

i already dynoed mine if it makes a difference.. i barely lost anything top end wise in 3rd gear..

 

[Violater101]

I saw your chart...I somehow feel you are making more power than that since I dyno'd 250 on 15lbs boost stock cat/intercooler/injector's/unported turbo/unported manifold & no fuel control...your 1/4 mile times lead me to believe thats true also. I believe you said you trapped at 108 or 109? in the 1/4 right at 13.7. I think with cam's you would trap somewhere around 112-114.

 

[Boosted97GS-T]

Violater, have you been to the track in your car yet? and also before your injectors and fuel control, how did it pull compared to after the injectors and fuel control?


i have a feeling i'm trapping around 100-102mph

 

[larryd]

yeah.. im thinking the same, the dyno #s just dont seem to add up

 

[Violater101]

I have only been to the 1/8 mi track so far and it was my very first time to run at a track ever. I don't have the exact timeslip #'s infront of me, but I ran a 9.3@79 1/8 with a 2.45 60ft on pump gas and 18/19 lbs of boost. My best 60ft was 2.35, and I think i would have broke 80mph, but I missed 3rd gear ...never thought that would happen. I only got in a few runs..the other times I didnt get any traction in 1st gear.

Also, the car was untuned with stock timing maps and -22% fuel global adjustment. I would never say base your 1/4mi on your 1/8mi trap, but u can usually get a good estimate ...which would be around a 13.9 1/4. What's great about this is like I said, it was on pump gas and street boost levels. From a roll, its way faster :>

As to answer your question about about the injector's, its hard to say because I wasn't able to run 18-19lbs of boost due to fuel cut ARGH :< I installed fuel control and injectors at the same time and now its on! The car still pulled great in 2nd gear with stock cat/inj's(no fuel cut at 17lbs boost)...r u using a testpipe? Even now the car pulls in 3rd gear(better so than before), but not like 2nd Gear.

 

[Boosted97GS-T]

yes i do have a test pipe, so i guess my car runs normal then, other than the huge boost spike , i really dont know what else to do with it, everyone was saying i would have boost creep with exahust but absoutley none of that just spike

 

[larryd]

i had boost spike as well but it was because of my boost controller.. I was spiking to 30psi and it would drop off instantly to 20psi.. i fixed that though by changing the one knob from in the middle to hard