What turbo should I buy? Options

[turnaround89]

I am getting ready to turbo my 1.8L engine. And I already know that you can't turbo a 914. But, what i would like to know is what are good cars to get turbo's off of?

I am looking for a small turbo that will spool quickly. Looking to run about 7 to 10 pounds of boost.

What turbo'd cars will give me a good turbo to use? I have been looking for ones on ebay, but don't really want to buy one there. I don't mind buying a used one, so going to the junkyard and getting one is definitely an option.

Which turbo?

[ottox914]

Some thoughts for you- Chappy beat me to the link to my project, so you've got that. Our engines are OLD SCHOOL- 2 valve heads, push rods, air cooled, and the cam in our engine is lame from the start. Air flow is airflow? Not really. A modern 4 valve water cooled DOHC motor will move alot more air more quickly and spool a turbo up sooner. Don't go to big on the turbo! I thought a subie wrx turbo would be fine, that goes on a 2.0 motor, mine was a 2.0 motor- sure, it would start to make some boost from 2k rpm, but to see the 7-10 psi you're looking for, it would not hit that target till nearly 4k rpm, and while the ride from 4k to 5.5k was pretty quick, the trip up to 4k was less fun than expected.

The best tool you can have to do this project is knowledge- not just asking on a board what might work, what have you done, but reading and gaining a deep understanding of how it works and why... I'm not being mean here, but if you're not sure what the gold thingy on the turbo is and what it does, you need to go to school, you're not even close to ready to start cutting and welding.

Here is your list of required reading:

Maximum Boost, by Corky Bell
Street Turbocharging, by Mark Warner
Turbo maps link: http://www.rbracing-rsr.com/turbotech.html

Memorize both of these and you'll be ready to ask the right questions and make the right decisions. Neither will have specific answers to questions you will have, but you'll know what questions to ask, and how to understand the answers you come up with.

Turbos make power 2 ways- 1, thru the speed of the exhaust gas hitting the vanes, and 2, by the heat in the exhaust. So in general, if the turbo you are considering from an OEM car was mounted close to the exhaust port on the head, you can bet the speed and heat of the exhaust from that motor were considreations by the OEM in choosing that turbo- so mounting it farther away from the head will reduce the speed/heat getting into the turbo, and reduce the performance of the turbo.

And, if you're doing a draw thru turbo, you'll need one with a carbon seal. These were far more common of turbos in OEM's in the 80's, so finding a "good" used one usually means finding one that at one time was good, and now is used up. Also, the engineering of the housings and wheels will be 20 yrs behind the current models available. Many currently offered turbos can be re-built with a carbon seal.

Research and consider water injection as well, to help cool the charge air, since an intercooler is not an option with draw thru. Its an odd balance, in that we want higher egt's to help spool the turbo, but to much egt will fry the head and drop valves seats.

Do your home work. Read alot. Surf alot. The internet is your friend.