Cam equivalency question

[Jed118]

I'm aggresively dismantling the head as it is going to a shop to get cleaned up, plained and a valve job done. During the dismantling process, two cam bearings were found to be worn to the touch, as well as two rollers were quite hard to operate. Also, I don't know what these are called, but they're the things the lifters "sit" in... let me see f I can get a picture...



these things, are they supposed to have logitudinal play? Most of them do, some seem seized and not move at all.

Additionally, one of the cam surfaces is oddly damaged, behold:



It's rough to the touch and has deep abrasions in it. Only this one lobe. What caused this? Also, my main question:

would it be recommended that I get the same 1.8L cam, or would a 2.0 or 1.6 be better suited? How about a 2.4? I'm building an all motor car fed by 2x2bbl Weber DOCE 45's and MSD, high compression, full 2.5 inch exhaust. looking at about 200 HP. What would be the best fit?

Here's pics of where those lifters go, in case you're confused as I am:



And some more pictures of the head itself, why not:

[citrus3000psi]

Yes they are lifters...

They shouldn't have any play when there pumped up with oil. Make sure to de-pump before putting them back in the motor and firing it up.

Insert a paperclip and push around at the botton until the "head" can be pushed in. You shouldn't have to force that hard, its obvious once you push that "valve" down.

[Jed118]

Yeah I know... I found a DSM site that explains EVERYTHING in detail... except I can't find any cam information!

[Professor Quest]

Well, that cam is history.

A lifter can NOT be LOOSE fitting either, cause oil is gonna BLEED right around instead of threw it.

A lifter GUIDE can be over-sized and sleeved or they MIGHT have over-sized lifters that would require boring out the guide hole. That could salvage that head.

Why the failure of a cam lobe? A rocker that is WORN OUT creates too muck LOAD on that particular lobe.

The chain reaction is set into motion by merely not changing the oil often enough. SLUDGE....is the enemy of ALL engines.

Btw...you would NEVER-EVER machine a head more than .004"!

A BEND in a Ali. head is very common...but you have the MEANS to STRAIGHTEN a BENT Ali. head vs. machining it.

Machinist that say to re-machine parts.... are either stupid, or want to CASH-IN ON YOU! Somebody has to pay for those machines.

SLUDGE...will BLOCK tiny oil holes thru-out an engine to-boot.

The pressure-side of oil going to a turbo is small....but the exit is HUGE cause the oil is returned as a VERY HOT MILKSHAKE, FOAM type.

It needs to be COOLED to become a liquid again, to be pumped again.
If not...the AIR is being pumped instead of oil into the engine. NOT GOOD!

If you look at the oil pan on a G54B engine, you'll note the GROOVES to aid in cooling the oil as it returns to the oil pan.

Guys that have modified a oil pan with a FENCE to prevent oil travaling rearward to prevent oil moving rearward is sometimes done INCORRECTLY.

You DO NOT WANT that fence to dump oil back into the CUP where the pick-up is located at. = too long of a fence = hoter oil is being dumped into the cup.

[jeffball610]

Honestly, my advice is to find another head. There is a ton of sludge in there. A decent head should at least look like aluminum, and not a black abyss. If there is damage to a rocker, then there is likely damage lurking. Also, you said that the cam bearings were worn to the touch. These heads do not have bearings and a worn area means that it's worn out. I suppose you could fix it, but you can find a decent used head for under $100.

As far as cam selection, my advice is to find people running all motor engines. I believe Magnus is running an all motor engine. Although I think it's a 2.1L. Cam selection between turbo and NA is pretty large. You might even want a custom grind considering you want to run carbs.

[Jed118]

The pictures are really bad, the head is actually decent. The bearings that are damaged are the ones that form "caps", the top part if you will: It's not a problem for me to go out and grab these two parts, a cam, two rockers and a couple lifters (for good measure, just in case)

No part of the head that can't be removed is damaged. As for the longitudinal movement of the lifters, I have found that this is natural. There is no lateral movement at all (ie they do not move side to side)

The Pony head I gave to my guy for milling was in much worse shape and it came out glorious!

In any case, I think I'm gonna look around for some cam profile cards, match up something good to my NA unit.

[89coltgt]

You cannot swap cam caps with another head, just get another complete head. Is this a 1.8 head?

[Bill Hincher]

[quote="Professor Quest



The pressure-side of oil going to a turbo is small....but the exit is HUGE cause the oil is returned as a VERY HOT MILKSHAKE, FOAM type.

It needs to be COOLED to become a liquid again, to be pumped again.
If not...the AIR is being pumped instead of oil into the engine. NOT GOOD!

[/quote]

are you saying the oil is boiled in the turbo? you say it needs to be changed back to a liquid?

[Bill Hincher]

when you see the type of damage to the cam lobe you have, it is usually related to a previuos head gasket failure, anti freeze in the oil produces an abrasive acid

Milling the head is a bad idea because your cam bearings are warped as much as the surface to the head, it is best to have the head straightened ( its not too hard) and maybe a finish cut once you have the cam bearing races straight

Jeff is right, you are working very hard to save a cylinder head that may have lost its 'temper' and wont hold its surfaces square after all that work. It may be best to find another

[Robert Venable]

Anyone have any information or videos on straightening aluminum heads??

[Professor Quest]

[quote="Professor Quest



The pressure-side of oil going to a turbo is small....but the exit is HUGE cause the oil is returned as a VERY HOT MILKSHAKE, FOAM type.

It needs to be COOLED to become a liquid again, to be pumped again.
If not...the AIR is being pumped instead of oil into the engine. NOT GOOD!

are you saying the oil is boiled in the turbo? you say it needs to be changed back to a liquid?[/quote]

Not exactly. the oil is AIREATED....WHIPPED into a FOAM. If that return line was a clear hose, you'd see it for yourself. The faster the spool...the more milkshake happens.

If you guys have a BLENDER in your kitchen.....same as a turbo, pretty much. And some turbos are not coolant chilled...that return oil is even hotter.

I was a Porsche 911/930 freak for many years. Those are air/oil cooled engines that had a oil temp gauge from the factory. When you approach 300*F oil temp...you'd better back-er-down, or pay the price.

Those cars had OEM huge oil reservoirs and optional oil coolers...but no oil pans.

[Professor Quest]

Anyone have any information or videos on straightening aluminum heads??

This requires a press with a bench lenght long enough to place a head on the bench.

Have a rosebud tip on your AC torch for WARMING it.

Caps installed on the head and torqued to spec.

Depending on how BENT it is...you would WOOD shim both the ends of the head up a small amount.

With a solid peice of heavy steel across ALL the cam caps.....press the very CENTER while you warm the head. It DOES NOT NEED TO GET VERY HOT!

Could you do it in your kitchen oven at 400*F...and haul-ass to your press in the garage? I don't see why not.

NO SIR! do not gauge the head NOT IN NEED of straighten just because the cam still turns with your hand. That sounds weird...not believeable, I know.
begin with a good straightedge. It will often have a PERFECT BEND near the two center cylinders...end-to-end, not sideways.

However....your CAM BEARINGS might already be RELAXED (allow the cam to turn easily) while the head is BENT by .030".

I would remove all the valves, springs, rockers, etc.

With a lil' practice....you'll be like, "Ah shit....that was easy!"

No, you don't need a $300 straightedge to gauge with. Just a TEMPERD straight edge of desent quality.

And....the 2.6L, Mellings make a stock cam with OVER-SIZED JOURNALS to RE-BORE/ALIGN BORE the cam bores. .005" & .010". They might build it for other engines too. The 2.6L oversized journals is about $105. Solids & hydraulics cams...differant part numbers.

But I do agree....replacement OEM USED heads might be dirt cheap. You got a scrap one? EXPERIMENT BENDING IT!

However AFTERMARKET HEADS..... are RECYCLED CRAP ALUMINUM!
Alabama...Marnels....CRAP!

EVERYBODY....call Vic Edelbrock and beg him! He makes the "good stuff"! NOT RECYCLED! Made in the good ol' USA!

If you WONDER why you continue to blow head gaskets...that head needs to be RE-TORQUED over & over until you have CRUSHED that crap material to it's fullest.

In late 87, the 88/89s got a HARDER Ali. head. Last time I checked there were still available BLANK for about $800. GULP!

I will have to re-generate those pics...cause I fricked-up and erased them.

[Bill Hincher]

I understand your practical experience on Porche, but that was mostly from spooling the turbo and then shutting off the engine without cool down time
an accumilator for oil is the best way to aviod turbo damage in that problem

the turbo bearings recieve the oil and return it, but there is no 'whipping' from the turbo in the oil, yeah there is heat , but in the Mits, you also have coolant cycling in the turbo

[77amc]

Just get yourself another head. They are 45-50.00 here at the pull a parts.
Dirt cheap, and even cheaper or free if "sometimes" getting the whole engine and selling the rest to recoup! That is if you have the room or space to have stuff sittin around.

E