Biturbo & Ghibli II Camshaft profiles?

henris42

Junior Member
Messages
37
Hi,

Does anyone have info for camshaft parameters (durations, lift etc), for standard Biturbo 18V and 24V, Ghibli, Racing and Ghibli Cup?

So the question is that is there a difference, and how much? Unfortunately the service manual comes rather short on this aspect.

I'm probably rebuilding the whole 2.24v engine next winter, and I'm thinking giving it a bit of an upgrade at the same time. I'm currently trying to cross reference all manuals to see if I could increase the bore to 94mm from 86, making it a 2.6L "high-revving" engine with quite bit more compression. That would be huge benefit as I'm planning to convert it to E85 fuel at the same time. Have to change the ECU though as well.
So while doing that, would be good idea to optimize the cams as well.
 

Zep

Moderator
Messages
5,196
I don’t have that detail, but perhaps someone like @Maurizio, who posted some details of the work he had done on Bi-turbo era cars might know.
 

henris42

Junior Member
Messages
37
What I gather from part numbers, the profiles are same in all models..

But related to this, does anybody know the sensor wheel patterns for crank and cam? I'd like to make a simulator for Megasquirt 3 before I pull the engine....
I did find the ignition firing angles, but no success with sensor wheels. I'm going to update it to direct ignition as well.
 

spacecadet

Member
Messages
365
I have a set of camshaft wheels at hand, can measure it if you still need the data? What values do yo need?
 

henris42

Junior Member
Messages
37
Ok its a hard one, I'd need angles dgr of cam angle sensor "1", vs TDC=0 dgr. Its a bit tricky measure, and I assume there are multiple angles, like in the crank!

Don't worry about that, I believe I can do the proper measurements myself next month, I finally got the Finnish government tax sheet for it (yes one more biturbo now officially imported to Finland!) so I can soon disassemble the whole car... ;) !

I already have a Megasquirt3 ready for it, and new direct injection coils just arrived. I'll also have to consider what I'll do to the turbos - maybe a little upgrade?

I'll keep you posted!
 

spacecadet

Member
Messages
365
Unfortunately the value you are looking for (degrees between SMOT and SCAM) is missing from the manual.

78095
78096

Looking forward for the updates, sounds like an interesting project!
 

spacecadet

Member
Messages
365
The datasheet I've attached is for 24v

The camshaft wheels have a single pickup point by default, but there are empty threaded holes every 90 degrees. Would those help?
 

henris42

Junior Member
Messages
37
OK, in that case the link I found must be for 18v.

Those threaded holes are really good thing, the simplest solution there is to make 180dgr arc, and put a hall sensor there. With the holes that is an easy fit!

For crank I'll probably go with 36-1 wheel, (1 missing tooth). I was thinking laser cutting two halves and welding them in place of the existing pins.
 

alfatwo

Member
Messages
5,072
Kent cams supplied the items in the engine of our Biturbo race car years ago, If I remember it was about 400HP which was useless against Ford Sierra Cosworth's!

Dave
 

henris42

Junior Member
Messages
37
Its oddfire, so it can go only so far, you cannot push the revs too high, I think there is tops in 6500 or so. You'd need at least counter vibration shafts.

But its fine for a street car. With E85, you can get a bit further.