RXP. said:
So, I spoke with Ken today.
Lovely chap. Long story short, if would happily fit a lwfw for me. However if it were him he would not fit one on a 7.1 c2s.
So that leaves me with:
PARR Motorsport yes
RPM yes
Ne no
Demort no.
and forum members pretty even split too.
Good to talk to you today.
I probably should explain in a little more detail my reasons for that view.
We have on many variants over the years fitted LWF from pre 89 to 997 onwards including many GT4s and so on.
As you may know we do have a performance outlook as well as normal routine work and servicing etc. We use a lot of datalogging rather than making the assumption of fitting and assuming all is well.
There are certain models which respond well to LWF and some that don't. And that statement is not in the sense that one works better than on another model, but more on the effect of the engine and power.
I won't give out full details but suffice to say
- don't assume because the LWF looks nice and shiny and made by a CNC process that it is 100% perfect and balanced.
- don't assume that the LWF is not affecting your engine performance just because you don't see check engine lights (CEL) on the dash
- don't assume that it is not retarding ignition without you knowing it
As some may know, misfires trigger a CEL when they exceed a certain threshold in a certain timeframe. We have seen (in a control test) a DMF giving no misfire counters against LWF giving misfire counters. The design of the LWF is sometimes at higher RPM the pickup is different.
As also stated certain engines are stronger than others. We have LWF on 1000+hp turbo cars, but the whole assembly is perfectly balanced before installation.
We recently finished a couple of custom pre 89 engines that we put onto full Motec control and on one of those we were able to trace issues down to the LWF. When we pulled that and checked, despite it being new, the LWF was not 100% true. When this was corrected, issues went away.
Harmonics do play a part. Without going into a long story, engine mounts for example whilst giving improved handling, can also cause power reduction (minor) due to knock control. If you think of the knock sensors on either bank, they are looking for noise. You create more noise, the ECU pulls back power until it no longer senses knock. We are not talking huge amounts but when you build two cars identicial and one just seems to that that little extra and you try and find why, amazingly it was engine mounts being semi solid that caused the issue.
AASCO are the best we have used as an FYI and many just rebrand their product.
I just wouldn't personally do it on NA 996/997 engines - GT3 etc is fine. The only time we have on those particular models is when building some track day engines and then the whole assmebly was balanced.
Ken