Hi
I have a golf mk2 1.6td. I have the factory turbo and a front mounted intercooler 10psi boost. If I get a bigger turbo will it increase the power by the same boost? What turbo shall I go for?
Thanks
You can get 20 psi from the stock turbo - no bother.
Boost controller and downpipe will sort that.
A bigger turbo is meant to generate higher boost pressures which will in turn increase power. Getting a bigger turbo serves no purpose if you are going to stay boosting at 10 psi.
If anything, a bigger turbo boosting at the same pressure would give you more turbo lag. If you want to stay at 10 psi then it would be best to get a smaller turbo to get faster spool up.
But really if you want to increase your power... Turn that boost up!
A bigger turbo is meant to generate higher boost pressures which will in turn increase power. Getting a bigger turbo serves no purpose if you are going to stay boosting at 10 psi.
If anything, a bigger turbo boosting at the same pressure would give you more turbo lag. If you want to stay at 10 psi then it would be best to get a smaller turbo to get faster spool up.
But really if you want to increase your power... Turn that boost up!
Actually a bigger turbo will flow more air at the same boost pressure. That'äs why people fit bigger turbos - when you have already turned up the boost and want more power, a bigger turbo is the answer. You can have the same power at 20 psi with a big turbo than 30 psi with a small turbo. Lower boost pressure in turn will lessen heat load and make thing easier on the head gasket too. A bigger turbo will add lag, but in every other respect performs better, even from a reliability stand point.
But of course, if one's only running 10 psi on the stock turbo, turning that to 16-17 psi would be the first thing to do.
so, you think 17 psi is safe for the stock turbo?
17 PSI is quite safe for the stock turbo. If it's the Garrett, some people run them up to 30 lbs and they take it. I wouldn't do that for a daily driver though.
Keep it at 20 or less and you should be fine.
Brendan
Brenden thanks for the input, I had no idea how much someone can learn here. Would you know of any sources for maps on these TB021 turbos? It seems as if the P/R will be right, but, I still need to flow 18 lb/min to reach my hp goal, and if the stock turbo will do it then I have saved a whole heap of money
If I cannot get a definitive answer I will go with a new GT.
There are some turbo map resources in the faq section. Not sure if the one you are looking for is listed. If it is not you can try the makers web site or post a specifc question for that map in this section. Someone may have it or know where to find it. Most cars that come with factory turbo's are set up rather on the safe side. There is generally quite a bit more you can get out of them with the right setup and safeguards put in place, boost and egt minimum, intercooler or water injection reccomended.
Make sure you guys add in your location so we will know who you are near.
jim