VHPD timing with Piper verniers

Topics relating to the Lotus Exige S1 (series 1)
ortope
Posts: 187
Joined: Sat Jun 13, 2020 11:40 am
Location: Switzerland

I bought my S1 from a swiss specialist, but I immediately noted that the car didn't run well, despite having a horrendous fuel consumption: 16l/100km on a swiss highway with an average speed less then 100km/h!

Furthermore I noticed that unfortunately everything that was "serviced" by the specialist was more or less screwed up.
Therefore I decided to start a ground up restoration and the engine was also disassembled.

Of course the valves clearance was checked and I found that 4 of them were to tight...

Then I checked the timing and, believe it or not, the timing was at least 20° too late on the inlet and on the outlet.
Both valves were still closed at TDC with the verniers positioned on the marks that were marked originally on the Piper pulleys (!?)
:o

Image

I took the timing data for the VHPD from Piper's website:

Image

To cut a long story short here is how the setting of the camshaft should be, after taking the belt apart and setting the camshafts
with a gauge...
Note: Only the inlet camshaft needed a fine adjustment of a few degrees.

Image

Image

This week the engine will be reassembled and then we will see if the cure was successful or not...

:thumbup:
S1 #016
User avatar
Fonzey
Posts: 1363
Joined: Tue Nov 27, 2018 12:17 am

Great work, more details on the car needed I reckon :thumbup:
ortope
Posts: 187
Joined: Sat Jun 13, 2020 11:40 am
Location: Switzerland

I also tried this pair of pulleys, but believe it or not, they were roughly 170° wrong.

Image
S1 #016
ortope
Posts: 187
Joined: Sat Jun 13, 2020 11:40 am
Location: Switzerland

Fine adjustment at its best...

Image

Inlet:
Image

Outlet:
Image

:thumbup:
S1 #016
ortope
Posts: 187
Joined: Sat Jun 13, 2020 11:40 am
Location: Switzerland

We are still optimizing the Emerald ECU, but the stinky VHPD is definitely cured!

For those that would be interested I could send them a short video with the engine running,
because I don' t know how to attach the video to this post!?
S1 #016
User avatar
andybond
Site Admin
Posts: 1701
Joined: Thu Aug 30, 2018 9:16 am
Contact:

Youtube for the video. Upload it there and share the link in here
ortope
Posts: 187
Joined: Sat Jun 13, 2020 11:40 am
Location: Switzerland



:thumbup:
S1 #016
ortope
Posts: 187
Joined: Sat Jun 13, 2020 11:40 am
Location: Switzerland



:thumbup:
S1 #016
johnfishcurtis
Posts: 504
Joined: Tue Jun 17, 2014 9:59 pm
Location: Nottinghamshire

:clap: :clap: :twisted: :twisted: 8-) 8-) :thumbup: :thumbup: Oh the sound of a K Series with VHPD's and cams!
ortope
Posts: 187
Joined: Sat Jun 13, 2020 11:40 am
Location: Switzerland

To optimize the carburation I have been told that it should be better to place the air temp. sensor directly in the airtbox.
Therefore we decide to place it in the hole of the breather pipe and redirect the breather hose in the gearbox oil catch tank.
I developed an adapter to place the sensor in the carbon airbox without damaging the part adding a new hole.

Image

A friend of mine (:thumbup:) was so kind and made 4 prototypes, two in aluminum and two in Delrin.
I think I will install the part made of Delrin.
S1 #016
Post Reply