OK. I have a D15b7 With A D16z6 Vtec Head (Still have to put it on but that isnt the point) What is a safe amout of boost to run from a turbo? And say I get a turbo that can put out lets say for example 13 psi. And I only wanted to run 4 psi. How do you make it only run 4 psi if it can run 13? I dont know anything about turbo and I may post more questions in this post depending on your answers so please keep checking back. I want to learn how turbo works so I can put one on my car..Maybe someone can tell me allittle on how it all works..Thank alot. :thinking:

 

To control the amount of boost you would change the setting on the wastegate. Most come stock at about 5 lbs. That shoul dbe more than enough to run on ur hybrid. Check out www.howstuffworks.com. that place will tell u everything u ever wanted to know about a turbo and many other things.

 

Yes, howstuffworks.com is great for an explanation on how a turbo works.

Most smaller turbos have an actuator wastegate. The wastegate controls how much boost you create. They have a "stock boost" level, which is usually about 3 or 4 psi. That means that without a boost controller, you will run that much boost.

What happens is when you create so much boost, it causes the actuator to open up and dump the exhaust pressure. You will keep running a specific boost level, but the excess pressure will dump off and not allow the turbo to create any more pressure.

With a boost controller, you can control when the wastegate opens and vents the excess pressure. They make both manual (which is usually a knob that you run vacuum lines to) and electronic (which works off of a valve and then runs wiring to the electronic unit).

If you need a better explanation just ask.

hih

 

A lot depends on your turbo's wastegate actuator return spring. You can check it with a vacuum gauge by connecting it to the actuator and see what PSI it opens at...

Some DSM turbos hold 11 PSI on the wastegate. My T-25 did. It might have been a freak of nature, but it did. My 16g does, too. I think 14b's hold between 8-10 PSI. That kind of boost would wreak havoc on a D15 shortblock (IMO).

It would help a lot to know what turbo you're referring to. If it's from a Honda kit, you should be fine running that pressure, but be careful if you're building a junkyard setup! Check that wastegate out before you go romping on it if it came off of some other car and you can't find those stats on it.

EDIT: A boost controller only lets you raise boost. I don't know of any that let you lower it below the default pressure of the wastegate's actuator.

 

Not to hijack the thread, but is there some reason why there are no turbo "kits" for the newer body style civics? It seems like every other mod in imaginable is available, but no turbos. Some problem in the newer motors? Not as strong as the older? I am definitly not much into the performance of I4's just more curious as to why the newer ones have been overlooked for turbo'ing.

 

i believe there ARE turbo kits for d17s and the new civic si K20 engines

 

all your general questions have been answered at this point....

As far as your motor, I would feel comfortable running 6 psi all day, 8-10 when I felt like I needed to prove a point good luck, and as poste before, let us know if you've got more specific questions.

 

I do have more questions.. I want to make a ebay turbo and junkyard setup because I dont have 3000 to toss away..I was thinking about a T3 Or T4 can I use the apropriate wastgate to run at 5 psi? and what wastegate should I get that is already set at 4 or 5? And is a T3 Or T4 oil and water cooled? Is there one that is just oil cooled.? Thanks for all the great answers. If there is a easyer to use turbo than the T3 Or T4 let me know your opinions...

 

a custom setup can be a great way to build up a good cheap turbo setup, but you MUST know what you're doing.
if you get a turbo that does nto have an internal wastegate, you can always get a tial external wastegate and a .5 bar or lower spring which would give you around 7 psi or less. (depending what you get)
I've never dealt with water cooled turbos myself, but oil cooled turbos require oil sending and return lines, (in which case you need to know thread sizes for the sender line and such to make it work properly

 

holy crap, it hasn't been mentioned yet, i cant believe it. im assuming you don't want to blow your motor up. two words for ya:

FUEL MANAGEMENT

bud, you gotta take care of the fuel issue. your injectors won't pump enough, your fuel pump probably isn't big enough. you need to manage the fuel. this is the main problem why motors blow up when running a turbo. there's numerous setups you can do. the one im doing on my prelude this summer is a new pump, bigger injectors, and an s-afc to control the air/fuel. and im only going to push about 5.5 to 6 psi's of boost. that pressure should be fine on a stock motor. anything more (like 10+) you're taking your chances on stock internals. if you're willing to dump probably 'bout 3 grand on your motor, then its a much different story.

do some research. this site will help you out more than you can possibly imagine. the search button is your best friend.

oh, also. here's a great writeup for a do-it-yourself turbo. hope it helps.
http://www.cse.uconn.edu/~yelevich/turbo/turbo.html