Nokkenasgraden en lift C20LET

Goeiedag.



Is er hier iemand op het forum die mij kan vertellen wat de graden en lift van standaard LET nokkenassen zijn?

Ook graag moment van openen en sluiten en lift in BDP.

Indien er ook gegevens bekend zijn van de (C)20XE zijn die ook welkom.



Alvast bedankt

www.Dbilas.de



Part No.: 14.050.013

Application: Sport C20LET



Duration 268

Peaktiming 112

Valvelift 10,7

Liftat TDC 1,1

Valve timing IO/IC - EO/EC 22/66 - 66/22

Price €New 587.17

Spring set Standard



Part No. 80.000.018

Vehicle type Opel / Vauxhall DOHC 16V C20XE Motronic M2.5 (NEW! Completely aluminum)

Diameter 126.0 mm

Price € 249.90





www.catcams.be

Part No. 4600748

# ONLY for dirt track applications and pro street use with adjustable engine management or carburettors



INTAKE

clearance [cl] 0.00mm

duration [0.1mm+cl] 267°

duration [1.0mm+cl] 228°

valve lift [cl=0] 10.95mm

cam lift -

peak angle 112°

timing [1.0mm+cl] 2/46°

lift at TDC [cl=0] 1.25mm



EXHAUST

clearance [cl] 0.00mm

duration [0.1mm+cl] 257°

duration [1.0mm+cl] 215°

valve lift [cl=0] 9.90mm

cam lift -

peak angle 112°

timing [1.0mm+cl] 39/-4°

lift at TDC [cl=0] 0.60mm



Part No. CSK5058 (set)

Astra / Calibra / Kadett / Vectra (-1993) 4 cyl-16v Mot.C2.0XE

CAM TYPE dohc dth

TEETH / shape 42 / circular

DIAMETER (outside) 125,50mm

WIDTH 27,10mm



http://www.sbdev.co.uk/Camshafts/Camshafts_20/Camshafts_20.htm" onclick="window.open(this.href);return false;



SBD spec gemaakt door Kent Cams.

Hydro cams up to 350bhp.

Mechanical cams up to over 400bhp.

Verniers ook beschikbaar.



Quote:

Originally Posted by vbi

I did an "home made" comparison of the LET and XEV cams.

I used a caliper and a goniometer.

Both cams have a duration of 120°

The XEV cam open (and close) 5° after the LET cam.

You have to regain that 5° of advance (overlap).

A tooth on the LET/XEV pulleys is 7.8° (360°/46 teeth)

For that reason the cheapest setup is to retard 1 tooth.

I tried on stock marking but didn't felt a big change and had a flat spot at low rpms.

I then set mine on a vernier at around 7° and feels good.

Haven't tried other setups.

Double the values if you prefer to talk of crank degrees.



Other usefull infos I have found so far:



LET lift is 8.5mm

XEV lift is 9.2mm

EDS lift is 10mm



Most of the x20xev cam you found around have the same code (R90400056) both for inlet and exhaust.

The inlet have an ident of "H" and an ident of "I" for exhaust. You found that code stamped on the outer ring of the cam.

Dunno the differences between the 2 as they look similar.



Cam timing is always quoted in crank degrees for good reason.



The xe cam has 4° more duration than the let

The xe opens 6° before the let (sorry I quoted exhaust cam originally which is 12°)

The xe cam closes 2° before the let cam.

The xe cam has 33° of overlap and the let has 27° so 6° more.

The xe cam has 9.5mm lift.

One tooth is 15° so half a tooth is ideal at about 7°



The exhaust cam is different again.



One tooth has also been known to cause emission problems as mot time due to the excess overlap blowing unburnt fuel into the exhaust.



Hopefully that clears up any confusion, half a tooth will work best.





http://www.max-boost.co.uk/max-boost/cylhead/cams_C20LET.htm" onclick="window.open(this.href);return false;



http://www.totalvauxhall.co.uk/resources/totalvauxhall/TOV76.tech_LPDF.pdf" onclick="window.open(this.href);return false;

www.Dbilas.de



Part No.: 14.050.013

Application: Sport C20LET



Duration 268

Peaktiming 112

Valvelift 10,7

Liftat TDC 1,1

Valve timing IO/IC - EO/EC 22/66 - 66/22

Price €New 587.17

Spring set Standard



Part No. 80.000.018

Vehicle type Opel / Vauxhall DOHC 16V C20XE Motronic M2.5 (NEW! Completely aluminum)

Diameter 126.0 mm

Price € 249.90





www.catcams.be

Part No. 4600748

# ONLY for dirt track applications and pro street use with adjustable engine management or carburettors



INTAKE

clearance [cl] 0.00mm

duration [0.1mm+cl] 267°

duration [1.0mm+cl] 228°

valve lift [cl=0] 10.95mm

cam lift -

peak angle 112°

timing [1.0mm+cl] 2/46°

lift at TDC [cl=0] 1.25mm



EXHAUST

clearance [cl] 0.00mm

duration [0.1mm+cl] 257°

duration [1.0mm+cl] 215°

valve lift [cl=0] 9.90mm

cam lift -

peak angle 112°

timing [1.0mm+cl] 39/-4°

lift at TDC [cl=0] 0.60mm



Part No. CSK5058 (set)

Astra / Calibra / Kadett / Vectra (-1993) 4 cyl-16v Mot.C2.0XE

CAM TYPE dohc dth

TEETH / shape 42 / circular

DIAMETER (outside) 125,50mm

WIDTH 27,10mm



http://www.sbdev.co.uk/Camshafts/Camshafts_20/Camshafts_20.htm" onclick="window.open(this.href);return false;



SBD spec gemaakt door Kent Cams.

Hydro cams up to 350bhp.

Mechanical cams up to over 400bhp.

Verniers ook beschikbaar.



Quote:

Originally Posted by vbi

I did an "home made" comparison of the LET and XEV cams.

I used a caliper and a goniometer.

Both cams have a duration of 120°

The XEV cam open (and close) 5° after the LET cam.

You have to regain that 5° of advance (overlap).

A tooth on the LET/XEV pulleys is 7.8° (360°/46 teeth)

For that reason the cheapest setup is to retard 1 tooth.

I tried on stock marking but didn't felt a big change and had a flat spot at low rpms.

I then set mine on a vernier at around 7° and feels good.

Haven't tried other setups.

Double the values if you prefer to talk of crank degrees.



Other usefull infos I have found so far:



LET lift is 8.5mm

XEV lift is 9.2mm

EDS lift is 10mm



Most of the x20xev cam you found around have the same code (R90400056) both for inlet and exhaust.

The inlet have an ident of "H" and an ident of "I" for exhaust. You found that code stamped on the outer ring of the cam.

Dunno the differences between the 2 as they look similar.



Cam timing is always quoted in crank degrees for good reason.



The xe cam has 4° more duration than the let

The xe opens 6° before the let (sorry I quoted exhaust cam originally which is 12°)

The xe cam closes 2° before the let cam.

The xe cam has 33° of overlap and the let has 27° so 6° more.

The xe cam has 9.5mm lift.

One tooth is 15° so half a tooth is ideal at about 7°



The exhaust cam is different again.



One tooth has also been known to cause emission problems as mot time due to the excess overlap blowing unburnt fuel into the exhaust.



Hopefully that clears up any confusion, half a tooth will work best.





http://www.max-boost.co.uk/max-boost/cylhead/cams_C20LET.htm" onclick="window.open(this.href);return false;



http://www.totalvauxhall.co.uk/resources/totalvauxhall/TOV76.tech_LPDF.pdf" onclick="window.open(this.href);return false;

Het wisselen van nokken had ik inderdaad al eens van gehoord.



Ik wou graag even de gegevens hebben van standaard nokken van C20XE en C20LET.

In de laatste reactie staan voornamelijk performance nokkenassen, maar op de link van max-boost staan wel bruikbare gegevens. Alleen als je daar goed leest heeft een C20XE nokkenas 255 graden maar verderop in het verhaal zeggen ze dan weer 260 graden. Dus nog geen keiharde cijfers.



In ieder geval bedankt voor de reacties! Zowiezo al weer wat wijzer van geworden.

Het wisselen van nokken had ik inderdaad al eens van gehoord.



Ik wou graag even de gegevens hebben van standaard nokken van C20XE en C20LET.

In de laatste reactie staan voornamelijk performance nokkenassen, maar op de link van max-boost staan wel bruikbare gegevens. Alleen als je daar goed leest heeft een C20XE nokkenas 255 graden maar verderop in het verhaal zeggen ze dan weer 260 graden. Dus nog geen keiharde cijfers.



In ieder geval bedankt voor de reacties! Zowiezo al weer wat wijzer van geworden.