I'll be happy to give you a hand...twisty b-road wrote:I'm looking into this at the moment (it's an AVY Lupo thoughbut there is always good info here)
I have some doubts as to whether the Schrick 256 degree are extreme enough for what I want. I should say that I don't mind loss of low rev torque. 170bhp at 7500rpm has been done in Germany
I have e-mailed Schrick and spoken to a few Shrick suppliers, but cannot get an answer as to why 256 is the most extreme profile they offer. Looking at other engines, conventionally speaking, I would be looking for a late 260/early 270 profile. It has been suggested to me that 256 is the most extreme profile they offer due to the variable timing on the inlet cam. I wish I could find out/understand for certain
A set of custom made piper cams would be over £1000, I didn't bother calling Kent or Cat as I thought the price would be the same
In my opinion replacing the cams and then not remapping the ECU will never extract the full potential of the cams as the engine still believes it's running the mild standard profile.
Besides, all AVY Polo's (2nd generation) are same as Lupo Gti'w from an engine standpoint.
And here it goes...
I did EXTENSIVE reading and talked a lot to Schrick before "investing" in these cams.At that time, the discution was on a level of .. "why aren't there more agressive cams" and now i realise Schrick didn't acutally make these cams for the Gti, as more like for the "variable timing" engines of the group.His answer to my question was that there where problems with the EPC when using more agressive ones.
Right now i know for a fact (after alot investigating work and discussion) that these cams ARE actually agressive for this car !!The original VW cams where in the range of 205 in /215 ex range, with the intake cam variable, as already noted.This makes a difference of ~50 degrees intake and ~30 degrees exhaust from stock !! Thats not mild by ANY standards.
As far as the ECU reprograming is concerned, it IS actually OBLIGATORY with these cams.And the main reason for this as i have come to believe is not actually the fueling part, as much as the IGNITION TIMING part, since its completely off due to the totally different cam timing.As already stated, a drop in effective compression might also amplify the low rev loss, but i'm not the one to lay a hand on the Williams head for now.....
It took me about the year to get the courage and money to decide to do it, and now the wait IS OVER.Next week im getting the car on the dyno, for a custom reprogram job.Its really weird but there are A LOT of Gti owners (even around the world) looking forward to the results.Thats a part of being a tuning pioneer of sorts.
.I'm keeping my fingers crossed and will let you guys know...
I hope it won't be disapointing...
P.S. 1)After some more reaserch i came to the conclusion (pretty logical and stupid of me not to realise earlier) that there CAN'T BE an adjustable intake geat (much like the VVTi Toyotas) since the intake cam is controlled by the ECU and sensors.Hence the "variable term".There can be though an adlustable Exhaust cam gear, but don't really know the usefullness of that.
2)Getting the Gti engine to 7200 rpm will be some task cause due to the Hydraulic lifters its like living dangerously.Most "normal" hydraulic lifters start having problems around 7000 rpm.There are however "high rev" hydraulics, but dont know if the Gti has them.
I couldn't get an answer from Schrick.
