Increasing turbo boost pressure... discuss

Post by **airhead** » 08 Sep 2006, 01:30

I have a 1.6TD syncro. You may remember me from such threads as the one about the intercoolers. How would I go about increasing turbo boost pressure? Is it an easy job? Whats required? Does the turbo have to come out? Is it a good idea to get more engine power as an initial step? Will it make a big difference?

Post by **woody1977** » 08 Sep 2006, 09:02

http://www.gusmahon.org/html/boostcontrol.htm

i'm into my jap turbo motors, so this is slightly different

.
i never got round to getting one of these put on my car. but its a very cheap way of increasing boost.

just dont go mad, otherwise pop.

i woulddeffinitely suggest getting a boost guage for the dash so you can keep an eye on what boost it's running.. if its too high you can reduce it until its at a safe level.

what is the standard psi the diesel turbos run at?

Post by **T2Andy** » 08 Sep 2006, 10:35

Think the 1.6TD are supposed to run at 0.5bar. Mine has been fiddled with by the previous German owner and runs around 0.75bar, it has a boost gauge fitted.

Don't know how much differance it makes to performance as I have never drive one with standard boost, but it does seem to pull OK.

Post by **woody1977** » 08 Sep 2006, 11:16

the grainger valves are only about £10 and are manually adjustible and easily fitted...

what cooling does the td have?

Post by **airhead** » 08 Sep 2006, 12:28

Its a sttandard cooling system. Id look into getting an oil cooler though if you thought it was necessary.

Post by **woody1977** » 08 Sep 2006, 13:19

does it have an intercooler?

water injection is a cheapish way of reducing inlet temperatures.

Post by **airhead** » 09 Sep 2006, 10:48

No it doesnt have an intercooler. Thats why I was asking what was involved in fitting one in a different thread. Im just trying to find out here if until then a turbo pressure increase is a viable way to increase my power and what sort of horsepower gains can I expect without pushing the turbo too hard.

Post by **vanjam** » 09 Sep 2006, 23:32

wow! I felt faster just reading this thread.More please, I'm thinking reverse polarity vacuum cleaners on top of my pierburg carb, watch that baby move!!! yeah

Post by **airhead** » 10 Sep 2006, 14:48

Im sure its been done before, Vanjam! Would be interesting to see the results of that one though!

Post by **HarryMann** » 10 Sep 2006, 19:31

Either a Grainger or Simple Bleed Valve ($15 on eBAy).. with the latter I'm running 12.5 to 13 psi on an AAZ. But you'll need to wind the fuel screw in about 1/4 turn or so to realise the performance improvement - which is quite dramatic (as is more smoke lower down unless you correct it)

You also need to block up the Blow Off Valve (about 10-12psi), these TDs normally run at 7.5 psi.

Post by **airhead** » 10 Sep 2006, 23:06

I reckon Ill give it a go so! So its really just a case of putting the grainger valve inline in the rubber hose that comes from the turbo to the wastegate actuator on the fuel pump then? How do you go about adjusting the grainger valve so its not running the turbo too hard?

Post by **woody1977** » 11 Sep 2006, 10:48

you just have to twist the grainger to adjust the boost. if you do get one, i would recommend a boost gauge so you know exactly what its running and wont risk your engine or turbo.

Post by **Simon Baxter** » 11 Sep 2006, 16:13

increasing boost pressure will do very little, other than make the engine run a little cooler.
You have to increase boost pressure and fuelling to get better performance.
Increasing fuelling increases engine temps.
These engines usually want work at 100k, in a lighter car they last 2-3 times longer.
What Im trying to say is that these engine are under a lot of stress due to their weeny capacity, you have to work them hard to get them to perform.

Before you start messing with boost pressure and fuelling you need to get it to a stage where it is safe to do so, or you will comprimise the reliablility and longevity of your engine.
So, fit a oil cooler.
Fit a intercooler next (or charge cooler[water cooled intercooler])
Fit a EGT gauge.
Fit a boost pressure gauge.
Then, and only when you are at this stage sould you consider adjusting fuelling and boost.
There are other things you can do too, fairly simple mods, im not going to post here because people will moan at me when their engine goes pop because they didn't do the full job and fit the oil and inter coolers!
You also won't achieve much if you try to adjust the boost pressure because the blow off valve will just release the extra pressure, so that has to be overcome too.

Post by **woody1977** » 11 Sep 2006, 16:41

you dont need to sort out the fueling.. as long as your not going crazy... and the upped boost alone will increase the hp..

but as you say, you need to do other bits to ensure the engine stays alive.

Post by **Simon Baxter** » 11 Sep 2006, 16:46

Er, okay.
So, Diesels only run at stoichometric at full chat.
They are not "Throttled", they will take as much air as you can give them, they are throttled by fuelling.
How will an engine that is given more air go faster? you need air AND fuel to produce more power.
Increase boost if you like, if you want more power you are p!ssing in the wind.
Increasing boost on a pterol engine will increase power, we are talking about Diesels.