FYI: Official Alien Build thread Started 2003, Alien Resurection is underway. Flywheel is finished - transaxle is bolted - Starter works Options

[iamchappy]

WOW!

[wbergtho]

Hey Rick,

Have you turned everything over to see if anything hits? Best of luck, and hope you can still get it out on the roads before the ice and snow start piling up.

We need another update...

Bill

[rick 918-S]

Hey Rick,

Have you turned everything over to see if anything hits? Best of luck, and hope you can still get it out on the roads before the ice and sbow start piling up.

We need another update...

Bill

Not yet, I still haven't installed the cams.

Some more back ground info on the extent of the damage. My heads were shaved 1mm. My compression is now someplace around 11:1 Because of the shaved heads I am using a 1.4mm Porsche thick head gasket. The factory normal is 1mm. The thicker gasket still doesn't re-align the cams correctly. I have to run offset cam gear keys. At this point I'm not sure what keys I need to use. The keys I have are Mercedes keys. They are not correct for my cam slot and need to be custom ground to fit. So... stay tuned. (IMG:style_emoticons/default/confused24.gif)

[byndbad914]

I've followed some of the bad luck, so best of luck this time!

Are the head cores hard to find? Is there a specific reason why you didn't just get two cores with less mat'l removed for the rebuild opposed to fixing the one that was damaged? I am thinking you could find a set with less removed and then the thicker gasket would put it back near stock location for the cam timing issue...

Additionally, what is the affect of not having the offset keys? Are the cams retarded or advanced? With stock cams and 11:1, if it is slightly retarded you might just run it that way (retarded less than 6deg) cuz that will bleed off some cylinder pressure, and with stock cams, maybe pick up some top end power. We all know the teener doesn't need the low end power (IMG:style_emoticons/default/laugh.gif) I have a rather wicked race cam in mine, so retarding actually hurt my power because I bled off too much pressure, but small cams I have found like a little retarding if you want to slightly increase top end.

You may have covered the reason already, but I am too lazy to read all of it (IMG:style_emoticons/default/smile.gif)

[rick 918-S]

This has been a long saga this summer. The trouble started before the last rebuild. I had a head gasket failure and a broken spring. This caused seat damage in one cumbustion chamber. I had the head repaired and cut. When I assembled the engine I may have had one cam advanced causing a valve collision or I could have just had a valve stem break, or I could have damaged a ring during install... Who can really know.

Anywho.. I brought my heads in to a head specialty shop to have them evaluated. The head guy told me it would cost a minimum of $ 900.00 plus parts to repair the damaged head. When I asked him how much these heads were cut he didn't know... He didn't even really know how to check them. I told him to box them up and I would come get them.

Now, an uncut 928 head is 24mm measured off a boss on either end of the head. Mine were in the neighborhood of 23.4 to 23.6mm. (one was cut like a wedge...could have been like that before the rebuild) That is in spec as you can use a 1.4mm gasket opposed to a 1.0mm gasket to bring the specs close to stock.

I figured I'd get a unmolested set. These are not easy to find or cheap when you do. I sourced a set of heads from a very reputable 928 source. They hit my AMEX for (are you sitting down) $ 1000.00. I brought these heads into my local Chevy guy machine shop with all the 928 head info I could gather. They measured the replacement heads and discovered they were at 23mm, needed intake guides and a couple of valves, and a resurface. I shipped them back for a refund and had my heads fixed. My heads are now 23mm, (at where the replacement heads measured)

BTW: For the guys that don't know, My engine is a euro spec "S" engine. It's factory rated at 300hp. Stock compression is 10:1 the cams are "S" cams, the throttle body is way larger that US spec engines as well as the inside diameter of the intake runners, the intake and exhaust ports are larger, the combustion chambers are smaller and the valves are bigger. The heads and intake are very desirable in 928 circles.

It cost me $ 770.00 including the welding repair of a very bad hole punched through the intake seat by the exhaust valve stem, new intake guides and 5 valves. The work looks great!

BTW: The complete gasket plus the added cost for the thick head set, rod bearings, Loctite case sealant and stuff were over $ 800.00.. This is not a Chevy kids.

[tdgray]

Damn straight aint no chebby for them bucks.

OUCH Rick... :insertmoneyflyingoutofthewalletsmilie:

[Joe Ricard]

For future reference (hope this is nt needed)
944 heads fit too. and they have even better porting.

Them Porsche V-8's sure are sexy compared to American Iron.

[Root_Werks]

Keep it coming together Rick, you have a one a million car for sure. (IMG:style_emoticons/default/driving.gif)

[byndbad914]

When I assembled the engine I may have had one cam advanced causing a valve collision or I could have just had a valve stem break, or I could have damaged a ring during install... Who can really know.

(snip)

new intake guides and 5 valves. The work looks great!

So cutting the heads causes chain slack which the tensioner takes up either retarding or advancing cams. Does one cam retard and one advance, or do they both advance? If they both move the same direction, how much (how many degrees)? If you advance or retard 4deg, assuming you don't lose too much valve clearance of course, won't make a huge difference with a mild cam that a factory would produce.

Also, were the other five valves bent? If you only have a single valve that had an issue (like snapping off (IMG:style_emoticons/default/sad.gif) ) then probably a valve failure v. contact with the piston. If it interfered enough to break it off, you would probably see bent valves elsewhere too. If the others needed replaced just due to guide problems and therefore stem damage, probably not an interference issue.

Lastly, have you looked into custom copper head gaskets? I have no clue as to availability for a Porsche, but for the 'merican V8 stuff, you can get them in a wide variety of thicknesses. We ran some .100" thick ones for a guy that bought used NASCAR heads with 38cc chambers to get the compression back down a little. They can be tough to get to seal, but I just put a very thin layer of hi-temp RTV around the water ports whenever I used them and got lucky every time.

[rick 918-S]

When I assembled the engine I may have had one cam advanced causing a valve collision or I could have just had a valve stem break, or I could have damaged a ring during install... Who can really know.

(snip)

new intake guides and 5 valves. The work looks great!

So cutting the heads causes chain slack which the tensioner takes up either retarding or advancing cams. Does one cam retard and one advance, or do they both advance? If they both move the same direction, how much (how many degrees)? If you advance or retard 4deg, assuming you don't lose too much valve clearance of course, won't make a huge difference with a mild cam that a factory would produce.

Yes, advanced one cam more than the other. Others are using 7 deg offset keys with less cut on the heads. The euro "S" engine is an interference fit engine. Every mm count's.

Also, were the other five valves bent? If you only have a single valve that had an issue (like snapping off (IMG:style_emoticons/default/sad.gif) ) then probably a valve failure v. contact with the piston. If it interfered enough to break it off, you would probably see bent valves elsewhere too. If the others needed replaced just due to guide problems and therefore stem damage, probably not an interference issue.

Valves were bent from collision.

Lastly, have you looked into custom copper head gaskets? I have no clue as to availability for a Porsche, but for the 'merican V8 stuff, you can get them in a wide variety of thicknesses. We ran some .100" thick ones for a guy that bought used NASCAR heads with 38cc chambers to get the compression back down a little. They can be tough to get to seal, but I just put a very thin layer of hi-temp RTV around the water ports whenever I used them and got lucky every time.

Copper gaskets are available. But this is an open top block. I'm not comfortable running a copper gasket.

[Joe Ricard]

Not chain
Belt. at the time of design it was the longest in history.

I sometimes miss my 928. Like everytime I see a Mustang being an ass and needed a whoopin.

[rick 918-S]

FYI: Time to bump this thread. It's been awhile.

I purchased a set of 32 valve 5.0 pistons that have been fly cut for the euro "S" 16 valve heads.

As soon as they get here. I'm bringing them down to the machine shop with one of my 4.7L blocks. I'm having the block bored out and the pistons fit.

This is what the 928 guys call a Hybrid. It consists of the 5.0L short block with the euro "S" heads, cams, spyder, and throttle body. The engine will be over 10/1 compression and according the what I've read these engines fully dressed with A/C power steering, ect are 350 HP. This is a 50 HP gain over my euro spec "S" engine.

Am I stoked? (IMG:style_emoticons/default/aktion035.gif) Ya, i'm stoked! (IMG:style_emoticons/default/driving.gif)

[McMark]

You should be! Post pictures when they come in...

(IMG:style_emoticons/default/thisthreadisworthlesswithoutpics.gif)

[Root_Werks]

Holy crap Rick! That is going to be one crazy ride. (IMG:style_emoticons/default/driving.gif)

[iamchappy]

Your catching up, one of these days were actually going to get to drive these ridiculous things.

[Gint]

I purchased a set of 32 valve 5.0 pistons that have been fly cut for the euro "S" 16 valve heads.

As soon as they get here. I'm bringing them down to the machine shop with one of my 4.7L blocks. I'm having the block bored out and the pistons fit.

This is what the 928 guys call a Hybrid. It consists of the 5.0L short block with the euro "S" heads, cams, spyder, and throttle body. The engine will be over 10/1 compression and according the what I've read these engines fully dressed with A/C power steering, ect are 350 HP. This is a 50 HP gain over my euro spec "S" engine.

Am I stoked? (IMG:style_emoticons/default/aktion035.gif) Ya, i'm stoked! (IMG:style_emoticons/default/driving.gif)

Giddyup!

[rick 918-S]

I was shocked when DHL rolled into the driveway on Saturday with my pistons! Woo Hoo! They were playing catch up because of the snow storm we had on Friday.

I going to contact US Chrome in Green Bay. They bore 928 blocks and coat the cylinder with Nickasil. I won't need the Nickie treatment but they are at least familiar with boring Rynolds 390. I'm working in Milwaukee this coming week. If they can do the job I may bring the block and pistons with me and deliver the block to Green Bay. We shall see.. (IMG:style_emoticons/default/idea.gif)

[rick 918-S]

Time for an update to this long journey. Some my know I broke a head stud while attempting to prep my block for boring. Here's the link for that nightmare!

http://www.914world.com/bbs2/index.php?sho...83351&st=20 T

The the jury is still out deciding the fate of this block. I hope to know soon.

I discussed the block boring with US Chrome in Green Bay. They only do Nickisil and don't have the tools for the special lapping the Alusil blocks require.

So if I get the broken bolt out of the block I will have my local guy do the boring.

Not much to report except it may snow this weekend, again... may 2, and still crap for weather.

[rick 918-S]

I've exhausted everything I can do to remove the broken stud from my spare block for now. Maybe the machine shop can get what's left out some day. I pulled the engine out of my car and tore it down. I found a galled cylinder wall and broken piston. After I dropped the valve in my 4.7 "S" engine, I purchased two used pistons and reassembled the engine. I think one of the used pistons I purchased was cracked or somehow damaged.



Here's the block.



I think this block can still be bored from 4.7 to 5.0. So, I'm back to extracting the studs. I have all but one removed. It's really stuck and I'm working on it slowly. If it breaks, I'm screwed. This is my last block.

Edit: up date: I just removed the last stud from my "S" block. I'm sending this one to the machine shop tomorrow.

[KELTY360]

Edit: up date: I just removed the last stud from my "S" block. I'm sending this one to the machine shop tomorrow.

(IMG:style_emoticons/default/smilie_pokal.gif) I followed the broken stud thread closely. That was some pretty creative stuff. Too bad none of it worked; I thought sure tapping for a left handed bolt would work.

Glad you got that last stud out. There's probably an immutable law of reality surrounding the obstinance of the last stud or bolt to be removed.