Author Topic: Max safe boost with 1.6 idi td engine? (Read 2905 times)

caddygtd · « **on:** October 04, 2005, 01:24:50 pm »

This is my first post on this forum after finding hours of reading material.
And before you tell me to search for an answer to my question, I already have.
It seems the consenus is about 15lbs of boost is a safe number for 1.6 idi engines.
But I've seen other posts where people are running 20-25 pounds of boost with no problems.

So what do the experts think is safe?

I'm going to have a custom 2.5" downpipe and exhaust made because from everything I've read the downpipe is the bottelneck to getting hp out of these engines.

Master ACiD · « **Reply #1 on:** October 04, 2005, 02:01:46 pm »

if you want to go with higher pressures dont forget a good intercooler. lower temps in means lower temps out!

caddygtd · « **Reply #2 on:** October 04, 2005, 02:30:57 pm »

Thanks for the reminder.
I am planning on running an intercooler, but I forgot to mention it.

vwmike · « **Reply #3 on:** October 04, 2005, 02:43:47 pm »

The biggest concerns with running a lot of boost is the integrity of the head gasket, and egt's. You can run a lot of boost, but not a lot of fuel (easier with a small turbo) which will essentially lean the engine out and it will run cooler. That will however raise cylinder pressures considerably. Think about the compression numbers on these engines. Minimum test pressure is ~400 psi, so if we cram one bar (14.7 psi) of boost pressure (twice atmospheric pressure) in there we will see roughly 800 psi of cylinder pressure. Restoring fuel Air/Fuel ratios back to what they originally were is where you will find the power, but be sure to keep egt's under control or you could melt a piston.

That said, there are few turbos which will provide more than about 20-25 psi efficiently so a compound setup would be best.....it all depends on how far you want to go.

caddygtd · « **Reply #4 on:** October 04, 2005, 04:44:43 pm »

Quote from: "vwmike"

Restoring fuel Air/Fuel ratios back to what they originally were is where you will find the power, but be sure to keep egt's under control or you could melt a piston.

I should have been more specific in my intial post, sorry about that. I plan on increasing fuel along with the boost by turning up/modifyting the injection pump, using gtd injectors, front mounted intercooler and hobbs switch for boost control.

Quote from: "vwmike"

That said, there are few turbos which will provide more than about 20-25 psi efficiently so a compound setup would be best.....it all depends on how far you want to go.

I plan on reusing the Garret turbo that came on my td engine and installing a boost gauge and egt gauge along with oil pressure and oil temp. I'm looking to get 115 reliable hp out of this engine, so it's nothing extreme just a good all around 1.6td that balances driveability and economy. I figure in an A1 chassis this will give me performance on par with an A1 GTI.