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Discussion Starter · #1 ·
so i did a t-bird set up on my F2T and it still breakin in (600 some miles) and i do have my stock boost controller hooked up. it boosts right up to the red which is twelve psi on the stock guage. so i took the WG actulator line and switched it with the boost line on the boost controller but still goes over 12psi. i hope i did not put on the t-bird waste gate. if so then i cant push under how many psi?


whats the max psi on F2T with t-bird FMIC full three inch exhaust, from DP like 2.75 in. i dont wanna blow it so i not boostin but its hard. i heard 9psi but then cuJ24ter is running 14psi and says it rich.
 

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I was running my T-bird on 15 psi STOCK IC, Injectors and fuel pump with no problems.
 

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One of the 4 t-birds i had i was pushing 18psi
 

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Discussion Starter · #9 ·
i got 2.5 in pipes and front mount IC too. i think ill go ahead and put another VAF on the because the guy who had it befor me messed with it. who know's how reliable it is.
 

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I thought 15 psi was max for a stock F2T with stock turbo... 15 psi on a t-bird seems a little much.
15psi is the max for the TURBO not for the ENGINE
 

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15psi is the max for the TURBO not for the ENGINE
I ran a T-bird at 17lbs for quite a while (19 years old,no rebuild), with full 3" exhaust, porting work that normally kills the stock turbo above 15lbs and some extra injectors.
Killed it adding racing fuel, couldn't boost more then 17lbs and didn't advance the timing, figure the heat from being to rich might have helped kill it.

It really all depends on flow not PSI (provided proper fuel, timing, heat levels are respected) with our stock turbo on say a 1.6l Impulse you be able to boost 18+ psi without blowing the stock turbo up, on our F2T it cant boost as much.
Larger intercooler, pipes and a larger exhaust will flow better then stock and make the max boost a little lower and the more you make the engine flow the lower the lever of boost required to overwhelm the stock or T-bird turbo.

Heat is the biggest cause of the stock and T-bird turbo's failure.
Heat caused by a small turbo housing and to much boost (on a proper tune).
Or
Under certain conditions/upgrades (such as: larger exhaust, upgraded pipes and intercooler, cold nights, bored out blocks, ported heads, custom manifolds, increased boost with advanced timing form the Zombie or Probi chip....) the stock turbo can outflow the factory fuel system, meaning you will start to lean out before achieving the turbo's potential boost limit, provided the engine doesn't run lean enough to detonate, the EGT's will get much higher, this heat can/will kill the turbo.
 

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so i did a t-bird set up on my F2T and it still breakin in (600 some miles) and i do have my stock boost controller hooked up. it boosts right up to the red which is twelve psi on the stock guage. so i took the WG actulator line and switched it with the boost line on the boost controller but still goes over 12psi. i hope i did not put on the t-bird waste gate. if so then i cant push under how many psi?


whats the max psi on F2T with t-bird FMIC full three inch exhaust, from DP like 2.75 in. i dont wanna blow it so i not boostin but its hard. i heard 9psi but then cuJ24ter is running 14psi and says it rich.
The added flow from the exhaust and cooler/pipes and the stock waste gate actuators inefficiency are what leads to higher base boost.
I built a 4door GT with .020 over engine, ported exhaust manifold, exhaust housing and O2 housing and full 3" exhaust (Manual rack, underdrive pulley and aluminum flywheel, none of which increase boost (possibly lower it)), with no boost controller the minimum boost in any gear was 10lbs.


With my 89mx6 GT the most I could boost on a T3 with stock mx6 waste gate actuator trying to hold the larger T3 waste gate flap shut was 3-5lbs no matter where I set the boost controller, when I dumped the exhaust before the hollowed cat boost would go up to 8 even 10lbs in 4th and 5th.
Later with a Port and Polished head and 2.5" exhaust, last winter the waste gate actuator snapped loose from the compressor housing and was floating opened, there was more boost lag but despite the waste gate flap being completely opened, with the cold air and extra flow I could get 8lbs boost (I thought the turbo was dying).
 

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i was talking aobut the stocker...but yes i understand ur point.
 

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im pretty sure 1FIEREGT here in T.O runs 17psi tbird all the time with nothing more then a pump? But the motor can take the boost no problem, its that small ihi turbo in general that starts blowing hot air past 18psi, the gains are minimal and wearing to the turbo.

Motor wise I havent discovered the limit for boost yet, cold winter and 22psi is crazyness!

What does everyone think the stock headgaskets and headbolts can take in terms of boost? Do these motors typically experience head lift?
 

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What does everyone think the stock headgaskets and headbolts can take in terms of boost? Do these motors typically experience head lift?
I would worry more about the age and state of the head gasket after 230 000km (if it's original) then head lift.

I haven't experienced head lift and haven't read any threads here about it happening, from what I have seen and read head lift will cause permanent damage to the head gasket so it isn't something that would go unnoticed.
 
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