What do I have?

Tadpole · 05-03-2009, 01:15 PM

Hi everyone.
Last weekend I pulled the engine out and this weekend I have the whole top end apart.
Apparently this enine has been apart before because the heads and cylinders already have numbers stamped on them.
Quick background---it's a '75 2.7 that someone already made changes too. It has Weber 40 IDAs. Updated Carrerra tensioners,turbo valve covers, backdated exhaust and the air pump emission stuff taken off.
Does anyone know what the spec for the cams are supposed to be. I am trying to find out if the cams are stock.

Casting numbers: 901.105.109.01
901.105.110.01.
Also the back end of the camshafts have grind marks on them like numbers were ground off with new numbers stamped on.
The numbers are :
104
102

No broken head studs. I think they have been changed already.
What do stock pistons look like. The ones I have are stamped on the top of the piston:
Made in Germany
Sp003
89.97
They also have the valve relief cutouts.
Just trying to figure out what I have. Thanks for any help

Steve@Rennsport · 05-03-2009, 02:55 PM

Mike,

Piston pictures help a great deal in ID'ing such things,....

Unfortunately, the common practice of regrinding camshafts leaves part numbers as unreliable in finding out what you actually have. Unless you have documentation from the previous owner or engine builder, the only way you'll accurately ID those cams is by sending them to someone with a Cam Doctor. Thats the tool that measures lift, duration and lobe centers.

Tadpole · 05-04-2009, 10:36 AM

Hi Steve, here are a few pictures.

Thanks for any help

tom1394racing · 05-04-2009, 10:58 AM

The pistons are RS spec 8.5 CR.

Tadpole · 05-04-2009, 03:25 PM

Thanks Tom,

Do you know if these are stock pistons for a '75 2.7. Are they better than stock or should I say are they better to run with carbs?

Steve@Rennsport · 05-04-2009, 05:40 PM

Mike,

As Tom pointed out, those are Euro RS, 8.5:1 pistons intended to be used with "S", "E", or Solex cams. These were designed for MFI or carbureted engines,...

Those cams appear to be Webcam's 104/102 grind which are the "Solex" cams (great choice).

All in all, thats a nice combination.

Tadpole · 05-05-2009, 06:05 AM

Thanks guys for the information. Is this combination going to be better than the stock 175 horsrepower rating. And if it is do you know about what it would be ( just a ballpark figure). I will also be running 1 1/2'" headers and a 2 in 2 out MK muffler. Thanks again

RSstop · 05-05-2009, 06:06 PM

Mike,
You didn't say if you are using carbs. I assume you are because 104/102 cams have a 98 degree lobe center which is not compatible with CIS injection.

As Steve said this is a nice combination and should feel much stronger than your stock 2.7 CIS. It should be similar to the 2.7 RS motor which was conservatively rated at 210 HP. Yours wont have the peak top end, but in the mid range it should feel as strong. I would guess 200HP.

Make sure you set the cam timing correct. Web Cam doesn't list the 104/102 cam anymore, so you may need to call them. Steve may know off the top of his head?
Lyn

JFairman · 05-05-2009, 06:35 PM

http://www.webcamshafts.com/
951.369.5144
ask for Laurie, she knows her stuff.

Tadpole · 05-06-2009, 05:15 AM

RSstop,
Yes , I am going to be using weber 40 IDA's. Thanks for the ballpark info. I was hoping for that.

JFairman,
Thanks for the link and phone number. I will definitely be giving them a call.