What effects spool up?
- Thread starter monka
- Start date
jamesbaa
Member +
what sort of an answer is that, "search google" why bother asking anything in this forum if you can just "search google", what is going on with people, i hope you feel helpfull now! :homer:
jayc-glanza17
Fresh Recruit
as far as i am aware mate, it offers;
quicker spoll than TD04
more power than ct9, or a tad more than ct9 hybrid,
but not the top end punch of a TD04.
hope thats more helpful to you mate.
quicker spoll than TD04
more power than ct9, or a tad more than ct9 hybrid,
but not the top end punch of a TD04.
hope thats more helpful to you mate.
Guye
Lifer
Two main factors affect spool up...
1. The turbo's characteristics in relation to the engine it's paired to.
2. Wastegate control methods used.
No 1 is pretty straight forward. For example if you were to take the little ct9 and put it on a 2000cc high compression motor, it will spool like a supercharger because of the shear volume of exhaust gases the larger motor produces. Take a td05 and put it on a low compression 1000cc motor and well...you get the idea. Once the housing somehow increases or optimizes the exhaust gas flow around the turbine, the response will incease.
No 2 is a bit more complicated but is probably being used in this case. As you know the wastegate controls boost by diverting some of the exhaust gases away from the turbine, slowing it down to a stable rotation/boost level. Changing you stock actuator with a uprated unit will help keep the wastegate closed more efficiently, increasing spool up response slightly. Also, with the stock solenoid controlling it wastegate begins to open very early in the spool up cycle, hampering the overall response of the turbo (lets say you start seeing boost @ 2500rpm using this unit). Most bleed valves and mbc, while being used to increase the overall boost levels, also have the added advantage of keeping the wastegate closed fractionally longer than the stock solenoid. With the extra gases acting on the turbine for a longer period, you will notice that you spool up is quicker, and peak boost is seen at a lower rpm. The limitation is that with manual units, the wastegate, while opening later, still opens progressively, so the maximum response physically possible for the turbo cannot be acheived.
This last bit has been debated on this site before: IMO, the ultimate way to increase your spool up response is by using a ebc with the appropriate gain setting adjustments. While these are far more expensive and complicated than other wastegate control units (this is what all actuators, springs & boost controllers are anyhow) they allow the user who is willing to invest the time in tweeking the settings to get the maximum response from the turbo. E.g. with a good ebc you can set it so that the wastegate is forced to stay shut right up to the milisecond where the desire boost is reached (even if that level is stock boost) the open to slow the turbine, stabilizing the boost. If set correctly, it will seem as if your boost "spikes" and holds at the set level until redline. That spike is actually the massive response you gain with such settings. Hope this helps.
edit: just thought I would cover all factors relating to "what effects spool up" while I was at it...sorry for the essay.
Last edited:
Monkfish
Member +
It'll be the exhaust housing causing the reduction in spool time. If the CT12 housing is smaller than the TD04 housing, then it'll concentrate the gasses into a smaller area and reduce the spool time.
The control of the wastegate will play some part in it, although that is more when reaching the maximum boost level as the wastegate is kept shut for longer rather than gradually opening as the boost increases (Which is what happens normally).
Be interesting to see some solid results though, a turbo that spools like a CT9 but throws out power like a TD04 will be very popular.
The control of the wastegate will play some part in it, although that is more when reaching the maximum boost level as the wastegate is kept shut for longer rather than gradually opening as the boost increases (Which is what happens normally).
Be interesting to see some solid results though, a turbo that spools like a CT9 but throws out power like a TD04 will be very popular.
Exactly, why bother asking questions when you have almost unlimited amounts of information all over the internet which takes very little effort to find. People need to start reading more on here as apposed to asking question after question thats been covered numerous times.
Ben
Starlet_Sam
Moderator, Regional Area Reps Supervisor & Gay Car
Exactly, why bother asking questions when you have almost unlimited amounts of information all over the internet which takes very little effort to find. People need to start reading more on here as apposed to asking question after question thats been covered numerous times.
Ben
Good thinking, close the whole chuffing site down and just use Google from now on, this Einstein has solved all our problems.
Guye
Lifer
Generally speaking any restrictions will hinder the turbo...small exhaust reduces the amount of gases passing over the turbine/creates back pressure...restrictive intake has a negative effect on induction (has anyone else noticed while these conditions are not ideal for optimum turbo performance and hp, they help produce loads of torque? I'll look into that further...) On the other hand, too free flowing an intake and exhaust can cause another problem, boost creep.
Guye
Lifer
Exactly, why bother asking questions when you have almost unlimited amounts of information all over the internet which takes very little effort to find. People need to start reading more on here as apposed to asking question after question thats been covered numerous times.
Ben
well i had no real need to ask the question or go searching for the answers but here this thread is, and i have read it, especially Guye's post (repped) and have learnt something new, so im sure others have 2.
Sheldon
Malta Area Rep.
yep nice post guye... ! altho you can find some answers on google a thread like this can put up better valid points!