[IT Manta]

I am continually finding that I cannot recall the Opel information that was second nature years ago.

I as assembling my IT motor last weekend but was stumped while preparing to fit my camshaft. I have a three bearing hydraulic camshaft and a four bearing hydraulic head. I do not find any oil supply holes in the spare bearing journal in the head. Common sense says there should be no problem using this cam. My other concern is that I may want the extra support of the fourth journal even though the valve springs are OE. Should I "blueprint" an OE four bearing hydraulic cam or should I run what I have?

 

[Jim Branham]

I had a question about a certain head, there was a question about 4 bearing cams going into a 3 bearing head. TGSI racing answered this question for me........

What Keith has told you is absolutely correct. There is no such thing as a '68 4 bearing head. What has probably happened is he has stuffed a 4 bearing cam into a 3 bearing head. There is actually nothing wrong with this. The 4th bearing just "floats" in the air. While it is not optimum, I have built "weekend warrior" and race engines like this.

I found this post by searching for my post by user name and picking the one titled heads. HTH

 

[davegt27]

you can install a 4 bearing cam in an 3 bearing head

but you cant install a 3 bearing came into a 4 bearing head

if i remember from my Manta Part catalog


i hope your using a 1.5 head

davegt27

 

[kwilford]

A three bearing cam in a four journal head will leave one journal with EXTREMELY large clearances. As in no resistance to oil flow, and hence no oil pressure. I have read (but have not seen) that you can install the fourth cam bearing rotated such that the oiling hole is misaligned, and therefore it won't be dumping a bunch of oil. But when you install new cam bearings, they need to line bored. Hmm, maybe not the fourth bearing if you can somehow remove it a reinstall it without affecting the other bearings. Anyone know? Where are the Bob's when you need them????

 

[nobody]

The cam bearings are one piece. It is possible to put # 3 in by way of the side cover with the cam removed. The question is why. If this is a stock grind replace it with the right one. There also has to be an oil supply for that bearing race. You could maybe turn the bearing to block the oil supply. I believe anything is possible but the possible failures have to outweigh the savings of using that cam, if you want this thing to have a long life. If it's weekend warrior turn the cam bearing and go for it. All you have to loose is the motor.

 

[IT Manta]

That's exactly whatt was done. The bearing is installed to block the oil passage. Not good practice Hmm.

 

[IT Manta]

Well I ordered a new four bearing hydraulic cam and lifters from OGTS. I cannot get any better than the right parts brand new.