Aussie Speed head gasket.

[circlepilot]

I bought a head gasket, that was advertised as an Aussie Speed, slant six, big bore head, gasket, P/N GSAP210E. When it arrived, it was a "Precision" head gasket. No where on the packing or in the instructions, did it indicate where the gasket was made. Is Precision an Aussie Speed product?
Norm

 

[pishta]

Was it imported? IIRC everything that comes into USA is supposed to have its country of origin labeled. I think customs could actually seize it.

 

[RustyRatRod]

What was the purpose of getting that gasket? Just curious.

 

[AUSA66]

From the p/n looks like they are made by Endurotec used to be Permaseal comes up as made in Japan

 

[circlepilot]

What was the purpose of getting that gasket? Just curious.

It has a larger "fire ring" for bored over-sized engines. In my case .060 over. I've been a little concerned with the Fel-Pro, stock gasket's size. My head has been milled .100 and the fire ring on the stock gasket is "real" close to the edge of the chamber. This so called "Aussie Speed" gasket doesn't come near as close. Plus I picked up some information about this gasket over on the /6 forum.
Norm

 

[RustyRatRod]

It has a larger "fire ring" for bored over-sized engines. In my case .060 over. I've been a little concerned with the Fel-Pro, stock gasket's size. My head has been milled .100 and the fire ring on the stock gasket is "real" close to the edge of the chamber. This so called "Aussie Speed" gasket doesn't come near as close. Plus I picked up some information about this gasket over on the /6 forum.
Norm

Yeah, I thought you might be gonna say that. You ever measured any slant 6 head gaskets? I have. I have a FelPro PrintOSeal I just measured that's between 3.520 and 3.540. Those Aussie gaskets claim to measure 3.6. How wide is the fire ring? 1/8"? A little more? I didn't measure that so I'm guessin. I think the standard 3.5 "whatever" will seal just fine at .060". Those Aussie guys are fulla **** until you get to like .100" over, IMO......no offense to our Aussie friends. I'd run the FelPro in a minute on one at .060 and never think about it.

 

[circlepilot]

Yeah, I thought you might be gonna say that. You ever measured any slant 6 head gaskets? I have. I have a FelPro PrintOSeal I just measured that's between 3.520 and 3.540. Those Aussie gaskets claim to measure 3.6. How wide is the fire ring? 1/8"? A little more? I didn't measure that so I'm guessin. I think the standard 3.5 "whatever" will seal just fine at .060". Those Aussie guys are fulla **** until you get to like .100" over, IMO......no offense to our Aussie friends. I'd run the FelPro in a minute on one at .060 and never think about it.

Your measurements are accurate...and the Fel-Pro, will probably work just fine...I'm about a few days from installing the head and I'll "mull" it over. What I was interested in is, if the seller (E-Bay) was not being honest in his description. I've sent the seller a request for an explanation.
Norm

 

[RustyRatRod]

Your measurements are accurate...and the Fel-Pro, will probably work just fine...I'm about a few days from installing the head and I'll "mull" it over. What I was interested in is, if the seller (E-Bay) was not being honest in his description. I've sent the seller a request for an explanation.
Norm

I understand and I've had the same reservations. Think of it this way. THey advertise those gaskets as "large bore" and at 3.6". From 3.540", that's only .060" difference.....even less when you consider it's .030" on each side. Stack up .030" on a feeler gauge. It's "not much" difference for such a high dollar gasket. In fact, the old NOS McCord gasket I put on the new engine in Vixen WAS 3.6" pretty consistently. "I should" have recorded the part number, but it didn't hit me until I had it on and torqued. It was one of those old "white" asbestos head gaskets. It also measured .060" uncompressed, which was the main reason I used it, trying to get compression down a little. So there are some "larger" bore head gaskets out there. My question is, does it make a difference under .100" over? I'm bettin not. It's better to be safe than sorry. Remember, Cometic will make you a head gasket pretty much to your specs. They are here in the states.

 

[Killer6]

The large-bore gasket allows for de-shrouding oversize valves & bore "notching", done right it's really a smooth transitional continuation of the chamber deshrouding to the limits of ring travel. Something I've done on other smaller bore, flow-starved engines like the 455 Olds, immediately agreed to by the "wary" owner after doing a back to back cyl swap on the bench for Him. "C" heads w/Mondello valves..., .030" over bore.

 

[volaredon]

On the head for my build I did nothing but try and smooth out the sides of a chamber, the head had more like crude "C" notches around the edges of a couple of chambers and went "over" the edges of a fire ring by about 1/2 the thickness of the fire ring. So I wound up getting an Aussie gasket to save all my time and work I have into that head. Yeah it's 3.6-something (3.660 sticks in my head) as I set an old fel pro (pre printoseal) on there, a stock factory steel shim style, a Detroit branded gasket and a Roll gasket, and the fire ring hung over on all of them. A guy who is near me that is on slant.org have me an Aussie gasket and said "get me another when you can" and I'm gonna run with that one.

That is unless my chamber OD shrinks a bit when they mill the head. I'm waiting for the machine shop that has it to call me with a CC size so I can tell them how much to shave from it.

 

[circlepilot]

My head was milled to achieve 44cc chambers, which calculated out to about .100. The deck was milled .025, I haven't opened the packing on the Aussie gasket yet, to lay on the head, but I have laid the Fel-pro gasket on the Aussie gasket and you can see through the clear packing the the fire ring on the Aussie gasket is definitely larger.

 

[volaredon]

yup. I measured several of them (fire ring diameter) with a dial caliper. I had a thread/question about this very thing, think it was on the /6.org site. 0.100ish shave to get down to 44 cc? what did yours start out at? 0.100" seems steep/ though I am disappointed that even after a 30-thou deck shave, my pistons are still 0.180" in the hole on my block. My block cleaned up at 20-over, so that was all I wanted it bored. I put stock type Silvolite pistons into mine.

being 0.060 thick vs 0.040ish like most other readily available gaskets, I know that more can be taken off the head when using the Aussie HG/ but for what I have for the rest of measurements so far, I'm looking at a target of around 48cc maybe 46 at the smallest.
I don't have a current CC of my head (waiting on mach. shop to call me with that info) but I'm hoping the "oops" on my head will shrink when milled, meaning that those CC numbers I'm hoping to get to would lock me into an Aussie, even if the outer dia of my chambers shrinks enough to use a regular HG.... if I ever have to pull that head again, once I get it back and assembled.... but I have asked what CC to expect my stock uncut head to measure out at, getting guesses at 54-56 cc so far and at 0.0066 shaved per cc removed, I was looking at a shave of "only" about 60-thou to get there and have the CR I want using the Aussie... Im going for just over, "as advertised in every manual known to Man that covers the /6" (which claims 8.4) I want about 8.7-8.8, definitely not over 9/ since I am building what I hope will be a 3 season driver, and I ain't forking over $.50-$1.00 PER GALLON for premium on every fillup, sorry, aint happenin.
and using the online calc link that 68Barracuda gave me on the other site, at 46-48 cc that will put me right in the CR range I think I want.
I got an Aussie HG I "borrowed" (I have to buy him one to replace it) from Slantzilla whom I don't believe is on this site but is on the .org site regularly and lives near me. I have like a dozen other /6 HGs here including 8, pre printoseal, gray asbestos looking Fel Pros, and 1 each of a few other different brands for a slant, Id love to be able to use what I already have here, as the Aussie ones aren't cheap. I'll probbaly be going to that guy on Ebay and buying his 3 pack (per-gasket, much cheaper than buying only 1 from him)..... 1 for "pay back" and 2 for ready spares in case I ever have to pull the head back off......

 

[circlepilot]

I've been working with another member here on the forum, Charrlie. He recommended the 44cc chamber, which according to the machinist, equated to the (about) .100 cut. The .025 that was taken off of the block deck, was done to remove all of the blemishes that were on it. This engine, had been rebuilt before (crank has been turned .030 and is now polished and balanced with a larger register hole for a bigger torque converter.) and the block had been resurfaced, as the engine I.D. could hardly be read, now you can't see any numbers at all. When I tore the engine down, I found an "all metal," very thin head gasket. I'm going to start assembling it this afternoon, cam going in first.

 

[RustyRatRod]

I've been working with another member here on the forum, Charrlie. He recommended the 44cc chamber, which according to the machinist, equated to the (about) .100 cut. The .025 that was taken off of the block deck, was done to remove all of the blemishes that were on it. This engine, had been rebuilt before (crank has been turned .030 and is now polished and balanced with a larger register hole for a bigger torque converter.) and the block had been resurfaced, as the engine I.D. could hardly be read, now you can't see any numbers at all. When I tore the engine down, I found an "all metal," very thin head gasket. I'm going to start assembling it this afternoon, cam going in first.

@Charrlie_S won't steer you wrong. He knows the slant 6 very well.

 

[volaredon]

Yup Charlie knows his slants.
The machine shop that has the head I'm gonna use on mine called this morning, finally had a CC number for me, mine is at 60cc. He had looked it up somewhere (seems like machine shop people have access to stuff that those that aren't in that industry, don't.) Said that was also what his lookup said it should be. Been waiting for that call to determine how much is want shaved from mine. I was wanting somewhere between 46-48 cc for my build, knowing the figure I've seen to shave per CC of chamber volume to lose is something like 0.0066" so knowing I had 12 cc to lose I did a quick calc in my head (hey I was driving at the time) and told him to go with 70-thou. Later I figured it out, 12 thou CC volume loss x 0.066 came back at like 0.78" to shave. But add that to the 0.030 off the block already comes to .100 total between block and head. With the 0.060 Aussie head gasket vs the original 0.020 steel shim, I can add 40 thou back, leaves a net added squeeze from stock to only 60 thou. Once I get it back and can lay one of these other head gaskets I have on there, which are more realistic 40-thou thick, if I can use it,(because of that fire ring issue) might be borderline too much for a daily driver on 87. With the Aussie gasket, at 70 thou off the head and 0.030 off the deck,I'd have to go back and look but as I remember that gets me to 8.7-8.8.
I'll have to figure out what it would have been stock, with the steel sh gasket and uncut block and head, will be dreadful. Probably what.... 7.5 if I'm lucky? Though the engine was apart when I got it, no pistons or rods to be had. So I couldn't measure the original in the hole number at TDC. I have a hard time believing that this engine would have had the pistons .210 in the hole as built on the assembly line? I have heard that silvolite adjust the compression height on o/s pistons to "make sure" that a new engine built with their pistons won't be any higher compression than stock original.
My question then becomes where did all these publishers get their numbers from when they listed engine specs in the manuals of the day?

 

[circlepilot]

BTW...I got a reply from the seller, (explanation) to my original question, (post) as to the origination of the "Precision" head gasket sold to me as an "Aussie Speed" head gasket. He stated that he "buys direct from Aussie Speed's inventory and they get their gaskets form the vendor, Precision. I'll take his word for it.
Norm