turbo question

[86turbozcs]

ok im looking into maybe upgrading my turbo. i have a turbo 1 rebuilt garrett ready to go on. my question is....maybe stupid but here goes... if i went with a better turbo what does it do for the boost?? does it make it boost harder? longer? spool faster? im kinda confused about it. any input would be greatly appreciated.

as always thanks guys

[89CSX#179]

well If ya get a bigger turbo and fuel upgrades, you can run more boost, but the bigger a trubo you have, the longer it takes to spool.

[86turbozcs]

ok thank you

[Dave]

Quote:

Originally Posted by 89CSX#179 well If ya get a bigger turbo and fuel upgrades, you can run more boost, but the bigger a trubo you have, the longer it takes to spool.

You'd think so. We have come so far a long in turbocharger technology, it's unreal. You can get a turbo bigger than your grandma's head and maybe twice that large and still hit boost in less than 3/10. You got dual ball bearing turbos, hybrid turbos, and with a specific turbo engineered exactly for your setup, boost can be seen faster, and intake charges can be held down.

So basically, say you got that Garrett... the exhaust housing is larger than the compressor housing, so if you got one wheel bigger than the other, will it not take longer to spin that wheel? Yes, so that's why our Garretts spool so slow, but wow when they hit, they hit hard!

Usually the larger the turbo, it means the more air you'll be running through it, such as exhaust and compressed air. But the bigger you go, usually the lower your intake temps, and usually the slower the boost response. So yes, the boost will come on "harder." Let's say you were using a Mitsubishi turbo, and upgraded to the Garrett, it comes on "harder" because the wheels are larger, and that causes less RPM's in the compressor housing due to the bigger wheel, which generates FAR LESS heat. Boost isn't measured in time, so no it doesn't come on longer. lol

Hope that book helps you.

Cya

[tryingbe]

Bigger the turbo, less it is going to heatup the air.

Cooler air means more power, if you fuel system can support it.

[OmniGuy123]

Quote:

Originally Posted by 86turbozcs ok im looking into maybe upgrading my turbo. i have a turbo 1 rebuilt garrett ready to go on. my question is....maybe stupid but here goes... if i went with a better turbo what does it do for the boost?? does it make it boost harder? longer? spool faster? im kinda confused about it. any input would be greatly appreciated. as always thanks guys

You should check out corky bell's book Maximum Boost. It is a good read, and a good reference.

A larger compressor wheel will flow more pounds of air per minute.

A larger turbine wheel will offer less exhaust backpressure, and allow the use of a bigger turbine wheel.

There are a lot of other variables, and side effects of the larger wheels. The wheels can behave differently when used in different housings. The T4 family of wheels being put in machined TII comp housings for example will have a much higher temp increase in the charge air. etc. etc.

[86turbozcs]

so without having a humungous intercooler should i maybe just stay with a stock garrett even if im wanting to boost at 18? right now im running at 14 with an above the intake intercooler from direct connection. im not sure how far ill go with it but i doubt past 18-20. my thoughts were of maybe using a afpr, 3 bar map and +40,s in the future. would the stock garrett handle 18-20 efficiently? i dont run the car on the strip or anything so i dont need to make big big power. it doesnt even take much more than what i have for me to have fun on the street and get some good kills around here. the other problem i have is to get a new turbo it would be setup like a turbo 2 and that wont work with my intercooler. i dont really want to go with another intercooler for the fact it looks cool with the hood scoop and it flows a hell of a lot more air than what i thought it would.

[OmniGuy123]

Quote:

Originally Posted by 86turbozcs so without having a humungous intercooler should i maybe just stay with a stock garrett even if im wanting to boost at 18? right now im running at 14 with an above the intake intercooler from direct connection. im not sure how far ill go with it but i doubt past 18-20. my thoughts were of maybe using a afpr, 3 bar map and +40,s in the future. would the stock garrett handle 18-20 efficiently? i dont run the car on the strip or anything so i dont need to make big big power. it doesnt even take much more than what i have for me to have fun on the street and get some good kills around here. the other problem i have is to get a new turbo it would be setup like a turbo 2 and that wont work with my intercooler. i dont really want to go with another intercooler for the fact it looks cool with the hood scoop and it flows a hell of a lot more air than what i thought it would.

The stock Garrett will start to show deminishing returns pretty quickly after about 18-20 PSI from what I have read.

I would immagine that the top mount IC would not be as effcient as the TII coolers due to locantion alone. Heat soak must be an issue. You could probably push it pretty hard, but the TII IC becomes a huge restriction much above 18PSI anyway.

A custom cal, AFPR, and some +40s would make for a lot of fun in that car. The DCIC is desirable for the novelty alone, so I say see how far you can push it. An alky setup would let you get away with a lot more boost.

[86turbozcs]

so say for instance i change to my rebuilt garrett, upgrade to a 2.5 swingvalve which i dont have on it and use my 2.5 inch downpipe and exhaust. I have the stage 3 comp from fwd, turbo 2 injectors and run 108 octane. if i use +40s, 3 bar and afpr it should have wicked acceleration up to 18-20 psi and then probably wouldnt get much more after that bc of the turbo? but i think that it would be enough for the streets correct?

[OmniGuy123]

Quote:

Originally Posted by 86turbozcs so say for instance i change to my rebuilt garrett, upgrade to a 2.5 swingvalve which i dont have on it and use my 2.5 inch downpipe and exhaust. I have the stage 3 comp from fwd, turbo 2 injectors and run 108 octane. if i use +40s, 3 bar and afpr it should have wicked acceleration up to 18-20 psi and then probably wouldnt get much more after that bc of the turbo? but i think that it would be enough for the streets correct?

Even with the race gas, I don't think that the TII injectors would be able to provide you with enough fuel at those boost levels.

The custom cal, +40s, and what not would be a better solution. Running 18-20PSI on a garrett is a lot of fun on the street. I would think about picking up a .63 A/R turbine housing to allow more exhaust flow at those boost pressures though. It will cost you a bit in spool up, but the turbo wont be choked off at higher boost either.

The SV, and DP would also be a good upgrade. I would go for the 3" pipe if you don't already have the 2.5".

This would certainly make for one fast, and fun street car. No doubt about it.