Turbo lag
#1
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Turbo lag
I recently got my seven. I use microtech aftermarket management. and turbo was claimed to be hi-flowed. also using a unifilter large sponge type filter.
well, first gear won't boost past 6.5 psi
second gear will bost to 9 psi on the dyno, but not on the road.
third gear gets to 6.5 psi in a decent amount of time, then lags and reaches 9 psi by 5k rpm.
is it just me been toying with small turbos all my life. or is this hella laggy? by the way, when boost hits, the car flies! (for 1000 rpm before i shift and wait again!)
well, first gear won't boost past 6.5 psi
second gear will bost to 9 psi on the dyno, but not on the road.
third gear gets to 6.5 psi in a decent amount of time, then lags and reaches 9 psi by 5k rpm.
is it just me been toying with small turbos all my life. or is this hella laggy? by the way, when boost hits, the car flies! (for 1000 rpm before i shift and wait again!)
#2
What is your boost limit supposed to be at?
What turbocharger are you using?
From what you described, something isn't right, but I'm not sure what. Even if you are using a really large turbo like a T78 or similar, you should still get 9psi WAY before 5k rpm... more like 2500-3000 rpm.
What turbocharger are you using?
From what you described, something isn't right, but I'm not sure what. Even if you are using a really large turbo like a T78 or similar, you should still get 9psi WAY before 5k rpm... more like 2500-3000 rpm.
#4
Rotary Freak
6.5 psi is the stock boot level. ANything after 6.5 psi is boost creep. Every RX7 with mods does the same exact thing you are talking about. Its pretty dangerous if it goes past like 12 psi without fuel mods.
Right now your minimum boost is 6.5 psi. At 6.5 psi your wastegate is fully open. The added boost thereafter is from the wastegate not being able to vent the excess pressure, therefor boost rises sometimes uncontrollably.
Try using a boost controller (like 20 bux) and set the level to about 9 psi. Watch for creeping past that though.
Wat kind of car and mods??
Right now your minimum boost is 6.5 psi. At 6.5 psi your wastegate is fully open. The added boost thereafter is from the wastegate not being able to vent the excess pressure, therefor boost rises sometimes uncontrollably.
Try using a boost controller (like 20 bux) and set the level to about 9 psi. Watch for creeping past that though.
Wat kind of car and mods??
#5
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turns out my car WAS running a hi-flo turbo
don't know in which way it was hi-flowed but according to a mate of mine, "that's not ******* standard! that's a T04!!"
Also have an aftermarket exhaust, possibly 3", haven't really measured it yet. But forms 2 x 2.5" tips.
I'm not running any sort of BOV, the previous owner took it out before they sold the car!
I changed air filters, and it lagged worse.
Still can't explain why it lags so badly though. My 1.5 liter engine spooled a T02, T25 and even a T28 in no time (with a AFM and about 5 ft of piping.)
SaabGuy: I never thought of this as boost creep. Always thought of it as free boost. I was always happy to find an extra bit of boost everytime i modded my cars. Thanks for the enlightenment!
don't know in which way it was hi-flowed but according to a mate of mine, "that's not ******* standard! that's a T04!!"
Also have an aftermarket exhaust, possibly 3", haven't really measured it yet. But forms 2 x 2.5" tips.
I'm not running any sort of BOV, the previous owner took it out before they sold the car!
I changed air filters, and it lagged worse.
Still can't explain why it lags so badly though. My 1.5 liter engine spooled a T02, T25 and even a T28 in no time (with a AFM and about 5 ft of piping.)
SaabGuy: I never thought of this as boost creep. Always thought of it as free boost. I was always happy to find an extra bit of boost everytime i modded my cars. Thanks for the enlightenment!
#6
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You need more restrictors in the vaccum line for the boost controller. This will make the boost come on faster and harder... Dodge turbos have these restrictors inline between the wastegate and the solinoid..
Turbo Dodge between 86 and 90..
Turbo Dodge between 86 and 90..
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Originally posted by GLHS
You need more restrictors in the vaccum line for the boost controller. This will make the boost come on faster and harder... Dodge turbos have these restrictors inline between the wastegate and the solinoid..
You need more restrictors in the vaccum line for the boost controller. This will make the boost come on faster and harder... Dodge turbos have these restrictors inline between the wastegate and the solinoid..
Or if i use those hose connector things it would have the same effect?
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#8
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You have to use the restictors.. The hoses swell under boost unless, you have check valves inline.. you understand that?
if you don't use the restrictors, your boost will be unstable, and spike and drop, depending how much the line swells under boost, thus allowing for more vaccum to be seen at the wastegate.
if you don't use the restrictors, your boost will be unstable, and spike and drop, depending how much the line swells under boost, thus allowing for more vaccum to be seen at the wastegate.
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