Do it... You won't regret it
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Do it... You won't regret it
Quote:
Originally Posted by OffTrack
I am very interested in a VNT. Spoke to my LR mechanic who was quite disparaging of the need for a VNT. He said much better value for money putting in 3" exhaust and removing cat. However, I see that robbotd5 has done this and the low rpm performance in a manual is still poor.Quote:
Originally Posted by robbotd5
So, offtrack, $2000 for the bits, what about installation and remapping costs? I already have a rechipped 2004 manual.
Other suggested alterative from my guy was to install a new turbo which has a larger inlet and larger diameter impeller but which is a straight mechanical swap. Also needs mapping to be adjusted.
Fitting a VNT is a straight mechanical swap also.
Anyone with a few tools and time can do it at home.
Larger compressor will make more top end. But take even Longer to spool up.
Mundy.
I would not call my performance poor but the lag is still there but nothing like it was when the car was stock. Removing the cat is illegal.My van is a big one at 23ft which saps the performance as you would expect. If a VNT spools up to boost faster than the stock Garrett then I will eventually fit one.
Regards
Robbo
Just got a box delivered today from Bas with a VNT and NNN Ecu with the need to communicate with the immobilizor taken off as well.
I'll let you know how it all goes
Not wanting to be derogatory about your mechanic but he doesn't know what hes talking about.Quote:
Originally Posted by Mundy
A 3 Inch exhaust and a decat is in NO way comparable with a VNT.
I did the larger intercooler decat and 2.5 inch mandrel bent with a 3 inch centre muffler as well as a remap
This combination was nothing like the VNT but all of it combined is pretty special.
I am also told that your mapping doesn't have to be changed with the VNT but you will benefit if you have it optimised
^x2Quote:
Originally Posted by djam1
and just to add to the above, a bigger turbo is going to result in more lag. The benefits of a bigger turbo that can flow more air are unlikely to be realised on a turbo that will only spin out to 4500 rpm, unlike a petrol engine that may get a chance to use the extra air at higher rpm.
Thanks, I willing to give it a go. However, can someone explain what the boost box is for (ie why do you need one?) and how and where it is installed?Quote:
Originally Posted by Tombie
Also, is the upgraded intercooler really necessary?
The Disco Td5 ecu is programmed with a maximum boost limit of something like 22psi. If the ECU detects a boost level higher than this it limits fuelling until the boost drops to acceptable levels. You've probably read about the "kangaroo hop" that occurs when the wastegate modulator isn't functioning correctly - this caused by the ECU detecting an overboost condition.
A VNT produces high levels of boost of earlier than the standard turbo and this can result in over boost conditions.
A boost box plugs in to the line between the ECU and the MAP (Manifold Absolute Pressure) sensor and lowers the pressure reading sent to the ECU to a point that doesn't trigger over boost in normal driving.
I'm not sure if the larger intercooler is absolutely necessary, but all the major tuning companies seem recommend the intercooler upgrade as a prerequisite for the VNT install.
cheers
Paul
Hello,
I have a VNT on my Td5 and had a stage 1 map for nearly a year went okay....then I got a great map.file from Td5inside and WOW.. had a over boost problem for a long time due to a certain boost box not working, this has now been fixed made my own, but a boost box would be high on the list, I still have my D2a inter-cooler as have been to busy to change to my water to air one. I am quite careful about driving without a bigger inter-cooler due to the EGT
But I couldn't drive a TD5 without a VNT now.
Ian