Boost levels and Rings

[triniVr4]

i am being told by at least one fellow VR4 and a LEgnun owner that the 2.5 V6's cannot handle 14lbs of boost fro long....that the oil rings inherently give up.

IS there any truth to this? I'm also beign told that the engine can withstand 400HP with out having to mod the internals...


help oh great ones!!!

[Wodjno]

i am being told by at least one fellow VR4 and a LEgnun owner that the 2.5 V6's cannot handle 14lbs of boost fro long....that the oil rings inherently give up.

IS there any truth to this? I'm also beign told that the engine can withstand 400HP with out having to mod the internals...


help oh great ones!!!

Seems a bit of a contradiction here..
/Hmmm

To get 400bhp you need more than 14psi.. /yes Unless your using NOS that is :evil2:

[Kieran]

14psi is about 0.9 Bar isn't it? A lot of members are using this level of boost with no apparent problems - Some are pushing even more through those little turbos!

[bradc]

Some people are running 14 or 15 psi early on in the rev range, but the turbos won't be able to supply much above 10psi towards the redline, they are just too small. If I wanted to get as much safe power as possible I would have the turbos running at 14psi up to 4000 or 4500, then taper off to 10psi at 6000rpm. Make sure you have your fueling sorted out as well, you'll need an emanage, or similar.

[Nick Mann]

Anybody heard of oil rings giving up on a 6A13TT? Not one I've heard of.

400 bhp is not easy to achieve on these engines, so quantitative data of what goes bang at that power is not available. As Brad says, the turbos will not flow enough air to get to those power figures. Several members are in the mid 300's and at least two have added 100 bhp of NOS to that. No one has killed an engine due to too much power AFAIK. The few deaths we have had can mostly be put down (arguably maybe) to leaning out.

[bradc]

Uc's car has 198kw at the wheels, which is on stock fuel pump, injectors, turbos. He has changed all turbo piping, has 2 air filters each going straight to a turbo, intercooler, external wastegates and an exhaust system (cat still in). It is running on a Link ECU and runs at 12psi until about 4000rpm, then drops to 10psi at 5500rpm, then further down to 9psi by 6500rpm.

At max power it is at 10psi, which goes to show that you don't need a huge amount of boost, you just need to get rid of as many restrictions as possible in the system, and get a decent computer in there. A standard VR-4 makes about 150kw at the wheels, so his car probably has about 360-380hp at the engine.

[bradc]

forgot to say one thing, his stock fuel pump is right at the maximum at that power level, and once it gets upgraded, we expect it to be up another 5 or 10kw at the wheels.

[triniVr4]

thanks for teh info guys....really appreciated..

[AllBeItMine]

14psi on those little turbos really isn't a lot of volume.

there are people with single turbo conversions pushing some big flow and getting around 300kw at the wheels with out changing the internals of the engine.

[triniVr4]

^^ and you?....how has your intercooler setup affected the volume of air that yu push through your stock turbos?