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914World.com _ 914World Garage _ Ick....my compression ratio is low!!!

Posted by: Mueller Apr 9 2003, 05:20 PM

If I figured everything out correctly, my static compression ratio is 7.7:1 as of now....I wanted to run the .060" copper head gaskets to help seal the cylinders while under boost, but those will drop it down to 6.9:1 compression...talk about anemic sad.gif

I'm only a few weeks away from having the motor back in the car and running, but the turbo install will take a few months I'm guessing...I don't want to drop the motor again to remove the heads to install the gaskets at time of turbo install, so I guess I'll have to live with a sluggish compression ratio until boost can be applied...

my numbers if anyone wants to double check my figures:
deck height=2.18mm (without .060" gasket)
bore=94mm
stroke=71mm
Combutsion Camber CC's=58.17


For some good news....my 16*7 rims with 205/45/16's have been ordered
The rims weigh the same as the same size 16*7 Fuch= 18 pounds...not too bad

Posted by: Brad Roberts Apr 9 2003, 11:06 PM

So.. why the copper head gasket ? There is a wire that the turbo guy's use in there heads/cylinders. I forget the name of it.. but its a phone call away. It expands with heat helping to seal the cylinder to the head. Similar to "O" ringing the heads on a SBC, but this material grows. I think the 993 Twin Turbos ran this stuff. Can we buy copper head gaskets for our 94's ??


B

Posted by: Mueller Apr 10 2003, 12:11 AM

The copper gaskets are available in 93/94/96mm, or 103/105mm sizes.

I've tried to find the "fire ring" gaskets but it seems to be a generic term.
O-rings made of copper are sometimes used on watercooled cars.

Posted by: Brad Roberts Apr 10 2003, 12:16 AM

I cant call him.. but you could... Call Todd Knighton at Protomotive. Ask him flat out what the best material is to use for a air cooled Turbo (unless you have determined copper is the way to go). I know how Bontempi seals his 12.5:1 engines. It requires machining the cylinders and heads.


B

Posted by: Brad Roberts Apr 10 2003, 12:18 AM

One more thing..

Is .060 the thinnest you can get ?? I would take .040 off the cylinders (heads cost to much to F-up) to get some of the .060 back.


B

Posted by: tryan Apr 10 2003, 11:50 AM

nirosist ring?

Posted by: Mueller Apr 10 2003, 11:52 AM

I found a direct source that has them in the following thickness ranges:

.022,.032,.040,.043,.048".054,.063,.070, .086, .093, and .125 inches.

http://www.headgasket.com/gaskets.html

$15 each

I'm ordering the .022" thinkness and should have them early next week.

Posted by: jonwatts Apr 10 2003, 12:17 PM

Geez that's expensive. If they want to charge that much they should at least say they are copper covered titanium.

Posted by: Brad Roberts Apr 10 2003, 12:19 PM

YES Tryan ! Nirosist. That is was what I was thinking of.

Mike... help me out. Tell me why you think the copper will work.

I feel your holding something out on me.


B

Posted by: Mueller Apr 10 2003, 12:20 PM

Still a little cheaper than aircooled.net which wanted 22.50 each for them.

With items like this, I'm glad I only have 4 cylinders to deal with....

Posted by: Brad Roberts Apr 10 2003, 12:49 PM

Answer my question....!!!

Throwing a titty fit.


B

Posted by: Mark Henry Apr 10 2003, 02:28 PM

Evil Ed has them on his heads. I think it's one of those "they say" type of deals. They say it seals better.

I also would like to know the thinking behind this.

Wouldn't it squish then be the cause of a leak after a few cycles?

Posted by: Mueller Apr 10 2003, 03:19 PM

I've got the skinny on the Nirosist (nickel compound) .....old school 935 technology.

The way to go is to use aluminum sealing rings with the head and the cylinder machined to create a step. Correct expansion rates, plus it's mechanically "fixed" in place.

I called Promotive, nice guy (cannot remember if it was Todd or not)...he is building a 3.8 twin turbo, twin plugged monster motor for his 914.

Copper gaskets suck according to him, but better than nothing and much cheaper than the $320 a set he gets for aluminum rings...shit, I've got a CNC, what the "f" am I bitching about? mueba.gif


I'll run the copper for now, I've got enough projects to keep me busy.

Posted by: Brad Roberts Apr 10 2003, 03:36 PM

OK. Cheaping out. I now understand fully.

Yes Mark, that is exactly what they will do. (Squish and leak later) UNLESS he runs the good head studs (but he is cheap).

B

Posted by: Mueller Apr 10 2003, 03:39 PM

Better head studs? I didn't know they exsisted? I thought nothing was available nut/stud/bolt wise for our motors.

Point me in the right direction oh-wise-one smile.gif

Posted by: Brad Roberts Apr 10 2003, 03:45 PM

Your joking right ???

Raceware... ARP.... The aluminum cylinder guys.

Come on Mikey.


B

Posted by: Mueller Apr 10 2003, 04:10 PM

Okay....on order and to be delivered next week:

ARP Thru-case bolt kit and ARP Head Stud Kit....


$400...ouch...this supposedly cheap 4 banger is getting expensive....


Now, any secrets to removing the old head studs and threading in the new ones? Should I timesert the case for the head studs?

I hope I sell some more needle bearing kits at the SSI swapmeet smile.gif

Oh yea....got access to Tony's shop?.....I need 10 pieces at 11.90.......please

Posted by: Brad Roberts Apr 10 2003, 04:25 PM

I have the tube from the last batch we ran. I can cut them on the Caltenbach.

I want you to do this engine correctly. Dont even think half ass around me. You have kicked ass on these other projects.. dont slack on your own.


B

Posted by: Brad Roberts Apr 10 2003, 04:26 PM

The head studs will come out by applying a *little* heat to the block end. I would clean the threads out, but the ARP's screw right into the block. The RaceWare HS use a insert that they come with.

B

Posted by: Mark Henry Apr 10 2003, 04:45 PM

QUOTE(Mueller @ Apr 10 2003, 02:10 PM)
Okay....on order and to be delivered next week:

ARP Thru-case bolt kit and ARP Head Stud Kit....


$400...ouch...this supposedly cheap 4 banger is getting expensive....



I hear you Mike

I'm still on the fence, to turbo or N/A Decisions, decisions!?!?!?!

I've gotta make up my mind, if I want to go turbo I want the crankfire Ignition. If I stick with the N/A I'll just use my Mallory.

What am I going to do, ah, lets see what's today? confused24.gif

Posted by: Mueller Apr 10 2003, 06:12 PM

damn...I almost fell off my chair..I just added up what I have in my cheap 2.0 and I've got $2250 into it so far..this motherf@#$er better run forever and let me spank Boxsters and 996's.....

Posted by: Gint Apr 10 2003, 06:34 PM

QUOTE
this motherf@#$er better run forever and let me spank Boxsters and 996's.....


Parked in your garage?!?! laugh.gif

Posted by: Brad Roberts Apr 10 2003, 06:50 PM

Mike,

People balk at me when I tell them 6k to rebuild their 2.0 to 110hp spec. and bullet proof.

"BUT I ONLY PAID 2500.00$ FOR THE WHOLE CAR !!!"

Correct. You got what you paid for...which was a ratty ass 2.0 914 that needed the engine rebuilt.

I hear it reguarly.

B

Posted by: jonwatts Apr 10 2003, 06:55 PM

QUOTE
Dont even think half ass around me.


Brad, when I'm around you I only think FULL ASS.

(next time don't leave the door so wide open)

Real content: I've heard of high-boost turbo guys epoxying their heads onto the block instead of using exotic gaskets and sealing rings.

Posted by: Brad Roberts Apr 10 2003, 07:07 PM

There is a first time for everything Jon (you thinking) I'm glad I inspire you to actually think. I would hate for you to exercise your brain more than once a day.


:finger2: :finger2: :finger2:



B

Posted by: Sammy Apr 10 2003, 08:11 PM

It's called niresist. we use it to weld to cast iron.

Posted by: Evill Ed Apr 11 2003, 08:42 AM

I basically used the copper head gaskets to get the deck and compression I needed. My heads were cut and my cc'c per chamber were low.

My 1.7L with 8.5:1 compression and stock aluminum head gaskets showed no signs of leaking, and I beat the hell out of that engine at 15-psi.

Mike, I wouldn't bother with the copper gaskets just yet. If I had a mill I would be inclined to cut a step in the head and let the cylinder nest into that.

I personally have not had head leaks on any of my type 4 engines even though "they" say that the heads will leak.

Ed

Posted by: Bleyseng Apr 11 2003, 09:03 AM

Ahh, the Jake Raby flame seal. Probably a way better seal than the copper gasket. Lap the cylinder to the head Mike and check it with dye. Too low of compression and that motor will be a dog at low revs until you get onto boost.
Geoff

Posted by: Brad Roberts Apr 11 2003, 12:22 PM

Ed,

this what we do on the 1.8 race engines. The jugs get machined and the heads are machined with some grooves. I cant take a pic of it... it doesnt show up (very small) but the jugs do sit into the heads without a head gasket (12.0:1)

B

Posted by: Evill Ed Apr 11 2003, 12:51 PM

You getting all of this Mueller? ;^)

Ed

Posted by: Mueller Apr 11 2003, 01:09 PM

Yep...and I'm even more confused as before wacko.gif wacko.gif

The gaskets are already paid for and are not returnable (custom order)
I do like the idea of machining a matched ridge in the cylinder and head, we'll see what I decide to do next week once I get the gaskets and do some research on this.

I'm also going to redo the CCing of my heads to ensure I didn't screw up the numbers. Maybe I read the burette wrong blink.gif
(if anyone local needs to borrow mine, let me know, I'm sure it'll be collecting dust for a long time once I'm done with this motor)
(I have the 100cc kit)

IPB Image

Posted by: Mark Henry Apr 11 2003, 03:07 PM

WOW!

I've been building bug engines for ages and all I have is a 100cc syringe and lexan plates.

wink.gif

Posted by: Brad Roberts Apr 11 2003, 05:00 PM

He called to borrow my setup and I told him I couldnt find it... I bet he was wondering how I lost a large glass object.

I use the lexan syrninge method also.


When I cant find it... I make anothe one...LOL


B

Posted by: Mark Henry Apr 11 2003, 09:31 PM

Mueller

Why don't you leave the copper gaskets out till you slap the turbo on?
Your going to have to yank the engine to install it.

what's some push rod O rings and exhaust gaskets.
mueba.gif

Posted by: Mueller Apr 11 2003, 11:12 PM

Mark,

I'd have to install new push rods as well....longer distance for them to properly activate the rockers.

Posted by: Mark Henry Apr 12 2003, 06:41 AM

Are you going with the Cr-Mo pushrods or is it adjusters that is changing the 'gee-I'm-a-tree'?

what all are you changing/doing?

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