Turbo readings and how to adjust

[Harry]

Hi all

Can someone please enlighten me as to what my boost gauge should be sitting on when cruising down the highway. She is a 2000 model with 50,000km's on the clock and I have recently blocked egr added a 3" exhaust, boost + egt gauges & dawes + needle Vv. The only time I can get the boost gauge to move is if I drive it like I stole her. I have adjusted the Vv all the way in and out without much change to the truck. The most I can get on the boost gauge is around 10 and when I remove the right foot it go's straight back to nothing. I do not have the option to put her on a dyno as I live on an Island. Any help would be appreciated.

Harry

[Bigrig]

Hey mate - when you're cruising it's more then likely in vacuum so nothing will show on the gauge (unless it's dual vacuum and boost). That's normal.

That said, you should only have to drop the boot in a bit (2000 ish rpms) and the turbo should be spooled up and boosting ...

[MudRunnerTD]

You wont actually achieve Vacuum on a diesel Scotty so no point running a Boost/vac gauge. I am assuming that the OP has a 3lt Diesel by his mods?

What Scotty says is right though bud, you will have NO Boost at idle and half boost off a set of lights if you drive easy, when you get up over 2000 and looking for that mid range then you will note a max boost number. 10psi is conservative and near factory settings and will be fine mate.

Unless you really want to go and play with the fuel pump then your boost adjustment will show a limited benefit. Have fun though ;)

Most boost gauges come with a little restricting plug....Did yours? did you fit it? This helps balance what the gauge sees and reduces spike readings, if you did not fit it then put that in mate. Where did you plumb in the boost gauge into your system?

[Bigrig]

You wont actually achieve Vacuum on a diesel Scotty so no point running a Boost/vac gauge. I am assuming that the OP has a 3lt Diesel by his mods?

What Scotty says is right though bud, you will have NO Boost at idle and half boost off a set of lights if you drive easy, when you get up over 2000 and looking for that mid range then you will note a max boost number. 10psi is conservative and near factory settings and will be fine mate.

Unless you really want to go and play with the fuel pump then your boost adjustment will show a limited benefit. Have fun though ;)

Most boost gauges come with a little restricting plug....Did yours? did you fit it? This helps balance what the gauge sees and reduces spike readings, if you did not fit it then put that in mate. Where did you plumb in the boost gauge into your system?

Uh duh!! Nice one bigrig!!! Didn't even take notice of the diesel bit!! lol

Sorry lads ... but it was late and you know what that means ... I was alcohol laden!!!! lmfao

[Harry]

Thanks for the replies guys. I have installed the plug and the boost gauge is fitted after intercooler and the gauge is sitting in a pillar pod. Before I had blocked the egr the truck used to have a reading on the boost gauge when I backed off the gas on the high way. Now she runs hotter and doesn't boost when I remove my foot from the gas on the highway. I have put on a 10" fan on the intercooler and this has seemed to drop the temp's by about 50deg (very surprised).Was the reason for getting the reading on the boost gauge before blocking the egr due to the recycling of gases? And if so this was making her run cooler, how do I get it back to those temp's? Would much change if I unplugged the dtronic?

[MudRunnerTD]

When you are Off the Gas you should have NO BOOST. The only time you should have boost is when you are on the gas mate, it certainly should not be the other way round which is kinda how i am reading your last post?? I am little confused now sorry.

Boost equals Turbo Spool Up and this is caused by Fuel ON. On a Petrol engine when you Fuel Off it will go into Vacuum and provide a Neg reading on Boost (below Zero). A diesel will just go back to Zero Boost when off the gas or coasting down a hill. Are you sure you have the Boost gauge fitted to the correct hose? Do you have any pics you can show us here?