L26, N42 head build cam shaft

[WogsRus]

Ok so there is about 4000000 cam suppliers and so forth.

 

I am using an L28 head on an L26 block, why? cos i can.

 

Got a question then, when buying a cam i assume i get one for an l28 internaly oiled, BUT, is the grind different for an L28 and an L26?

 

Sorry but whilst i have done about 10 engine rebuilds, i have never did any major modification.

 

Any advice would be great.

 

Alternative is use the cam towers form my E88 and externally oil cam?

 

Humm any help would be great

[kalium]

You want an internally oiled one, and whichever grind takes your fancy as long as it isn't too wild for the springs.

[Riceburner]

You can use either.... I've been told to use externally oiling cams by many different people. Think it was something about the internal holes clogging up and causing damage. Not sure if there's any truth to this but I've never had any problems 

[dazzed]

you should select your cam carefully before fitting a N42 to a L26,

[WogsRus]

Well hence the question, HOWEVER we have just discovered that my brothers L24e head is an MN47 as such, 39cc dish with full quench, i think the CR would work out to be about 10.3:1 with flat tops.

 

Humm her's thinking

 

I have no idea as to who to ask about the cam shaft

 

TA

 

 

[kalium]

I didn't realise we had those heads here in Oz.

 

Well hence the question, HOWEVER we have just discovered that my brothers L24e head is an MN47 as such, 39cc dish with full quench, i think the CR would work out to be about 10.3:1 with flat tops.

 

Humm her's thinking

 

I have no idea as to who to ask about the cam shaft

 

TA

[stevo_gj]

Well hence the question, HOWEVER we have just discovered that my brothers L24e head is an MN47 as such, 39cc dish with full quench, i think the CR would work out to be about 10.3:1 with flat tops.

 

ah, so the MN47 head is quite different to the N47. Do you have the intake and exhaust valve sizes? I'll add it to my thread: http://www.viczcar.com/forum/index.php/topic,6012.0.html

[WogsRus]

sure can, heer is a pic of one i found elsewhere.

 

I have not got chinnas head off yet but looking into the head with a pin cam that is what it appears to be

[stevo_gj]

Cheers,

 

If you could post the dimensions for the intake and exhaust valve in mm that would be sweet. 

[WogsRus]

Will do, the pic os of a mates head he got from the states but looks like my brothers.

 

 

From meory they are the same as N42 in size

 

[.]

I am still confused.

 

One of the guys here in Bris has problems with his head. One of the problems is a couple of worn lobes on the cam. It is an L26. I assume (as I have not checked it out yet) that the engine is quite standard and therefore will probably still have a standard cam with a oil spray bar. I am expecting to find the spray bar either broken or clogged near the worn lobes......Anyway I have some standard cams at home but I am not sure about compatibility.

 

If I take a cam from the same type of head (eg N47) will it work in another N47 even if one was an L24 and the other a L26?

 

What about the standard cam from an L28?

 

We need a cheap option to get his car going again.

 

Also how should we clear out any blockages in the oil spray bar?

 

Any suggestions would be greatly appreciated.

[d3c0y]

You shouldnt have any problems using an internally oiled cam on a head with a spray bar, obviously the solid type are also ok.

 

FWIW The L26 cams with a C stamped on the end are supposedly the biggest of the stock cams but all the factory cams are pretty mild.

 

In theory you should use the rocker arms that go with the cam you putting into the head.

The wear patterns in the cam lobes and the pads on the rocker arms bed in like piston rings in a bore.

You can probably get away with out doing it but you do run the risk of again wearing the lobes out premiturely.

 

Also if there is lobe damage you would definitely want to check the contact pads on the rocker arms thoroughly for damage.

 

In my opinion if you are going to the effort of swapping the cam you should put a mild regrind in there too, will make the car go a bit harder. Stewart Wilkins Motorsport sell refinished rocker arms if you want to put 'new' arms in.

[.]

Thanks for the advice. Its funny that you mention checking the contact area of the rockers. I mentioned that to him this morning. as for the regrind, I would normally agree but this is just a stop gap to get the car on the road while he rebuilds an L28. We only need this engine to run for 3-6 months and the cost is the biggest constraint as the need was unexpected.

 

We took the head off over the weekend. The cam was a shocker, two of the lobes had groves about 1mm deep. The rest were normal wear (to the naked eye/finger). After inspecting the head and block we are reasonably confident it is just a blown head gasket (there was a black mark on the gasket at the back of Cyl 6). Plus the gasket and head separated without any effort (didn't seem stuck together at all).

 

The spray bar was ever so slightly bent but I don't think it was enough to cause an issue. We flushed it out and all the holes seem to flow ok. However I do wonder if it is possible for the two suspect holes to be pointing slightly off the cam lobe?

Anyway, it probably doesn't matter, even with reduced oil it should still last a couple of months. (fingers crossed)

 

We put a new gasket in and the head back on. The engine is coming together again. We should know the result within the next week.

[d3c0y]

I would want to get to the bottom of the odd wear - if you start breaking stuff at highish RPM you could lose the whole head.

[.]

I would agree except this engine really doesn't matter. He has a another engine on its way.

[d3c0y]

Let him know I'll take the head and sump when he is done with it!