Rr Dissapointment

[mfield 20]

Have you checked the cam timing yet ?

[mbayley77 0]

Have you checked the cam timing yet ?

 

No not yet.

 

I need some help on cam lobes though! Please take a look at the pics below. Can anyone tell me what the standard MI cam should be like? The rounded lobe one or the pointy one. Also the pointy lobe one measure approx 36mm at its lobe and the other one measures 37!!!

I have two sets of cams as per the rounded 37mm cams and one set as per the pointy 36mm ones. The 37mm roundy ones are in the car at present.

 

Anyone come across a difference like this before?

 

http://i8.photobucket.com/albums/a7/mbayley77/DSCF0086.jpg

http://i8.photobucket.com/albums/a7/mbayley77/DSCF0085.jpg

 

edit; image sizes. PM sent.

Edited March 13, 2006 by pugtorque

[mfield 20]

I would hazard a guess that the the roudy 37mm ones have more lift and duration than the pointy 36mm ones, normally indicating uprated cams

[mbayley77 0]

That was my thoughts. If it is then great cos i have two sets.

 

The pointy ones have markings stamped into the ends of em but cant remember what they say. Can get them tomorrow if it will halp anyone. The other roundy ones do not have any markings on the end of em.

[veloce200 3]

If the oil in the bore only brought it up 5-10psi then I'd guess at burnt out valves/seat or incorrect valve clearances or even slightly bent valves. (I once downshifted my Fiat 105TC from 2nd to first (by mistake I wanted third but the gearbox had a mind of its own!- equated to 12000rpm !) Mad thing is it still ran - just very tappety where I had bent 4 valves. Damn tough engine !

Edited March 11, 2006 by veloce200

[pug309twin40s 1]

well if the pointy cams have been stamped on the end of them then there proberbly uprated ones as most uprated cams get stamped on the end of them where standard cams dont

 

 

i would strip your spare cyl head and rebuild it and clean the rust of the pointy cams then remove the cyl of your engine and fit the spare head after being rebuilt wiht new headgasket etc.

 

then you should be up at 200psi and bk to full power.

[les3002 0]

check the cam timing first, just to be sure

[mbayley77 0]

well if the pointy cams have been stamped on the end of them then there proberbly uprated ones as most uprated cams get stamped on the end of them where standard cams dont

i would strip your spare cyl head and rebuild it and clean the rust of the pointy cams then remove the cyl of your engine and fit the spare head after being rebuilt wiht new headgasket etc.

 

then you should be up at 200psi and bk to full power.

 

Think this is what i shall be doing except rebuilding the head thats on it now as it the others are f*@ked.

I have decided that I am not going to spend any money on this engine now and gonna put money into a new engine from a 306 or something where i can have history etc. I have enough bits in the garage to rebuild the head for no outlay so gonna give that a go first so it doesnt cost anything.

 

Does anyone know the stampings on cams if i find out the numbers?

Would love to also know the difference in the two sets of cams in the pictures. Were they different on the bx gti to the mi16.

[jacobs53 0]

sounds like its definitly cam timing, low compression on all cylinders could be too much overlap or wrong opening times compared with the cylinders.

 

Id say your first check would be the cam timing

 

lee

[mbayley77 0]

well if the pointy cams have been stamped on the end of them then there proberbly uprated ones

 

My question on these cams is why are they smaller to the lobe which would equate to less valve opening and more pointy on the lobe which would mean a shorter duration? Surely these things do not equal more power etc.

[mbayley77 0]

Just been and checked the cam timing, although i havnt checked the crank position both of the cam pulleys line up with the locating holes so i dont believe the cams have turned in relation with each other.

 

Noticed that the cam pulleys had paint on them E and I but they were the wrong way around, the exhaust one was on the inlet side and vice versa.

 

I also noticed that both had a nummber 2 stamped into them. Are the cam wheels different in any way and what do the numbers relate to?

[B1ack_Mi16 67]

Just been and checked the cam timing, although i havnt checked the crank position both of the cam pulleys line up with the locating holes so i dont believe the cams have turned in relation with each other.

 

Noticed that the cam pulleys had paint on them E and I but they were the wrong way around, the exhaust one was on the inlet side and vice versa.

 

I also noticed that both had a nummber 2 stamped into them. Are the cam wheels different in any way and what do the numbers relate to?

 

The (2) number means it's a 114 deg centerline pulley. So there's no difference between them.

The XU9J4Z have (3) pulley on the inlet, that's with 111 deg centerline.

[pug309twin40s 1]

my old goodwood engine and my new mi16 engine both have number 2 pulleys on them. so i wouldnt worry about them as long as they line up as they should.