Use the better gasket.
All Small Six 200 Aussie 2V Build
- Thread starter StarDiero75
- Start date
This relates to all small sixes
My reply glitched. See the last post on pg 2
So based off the numbers I have (I was able to pull up my old MATLAB file, my deck height is .021". According to the aussie flat tops, they are 1.530", while the factory 1120s (which I believe I have) are 1.500". This puts me .009" over the deck, right? Or do I need more measurements than this?
According to my math, 7.8 from centerline to deck, stroke/2=1.5645, rod length=4.715, factory piston CH=1.5, leaves .021 for deck height, so it would appear my motor has never been decked. Unless I'm missing something here.
According to my math, 7.8 from centerline to deck, stroke/2=1.5645, rod length=4.715, factory piston CH=1.5, leaves .021 for deck height, so it would appear my motor has never been decked. Unless I'm missing something here.
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According to my math,
With .030 bore, felpro .050 gasket, -0.009 deck height, flat top hyper eutectic pistons, 58cc chamber, static CR is 9.43 which is great.
W/victor .045 gasket, CR is 9.55
With .040 bore (in case I need to bore), felpro .050, -0.009 deck height, flat top pistons, 58cc chamber, static CR is 9.47. W/ victor 0.45 gasket, CR is 9.60
A little unshrouding may happen with the new valves so I may end up perfectly at 58cc. Factory chamber is 56-58 so hopefully it hasn't been decked much in its life. Worst case is to unshroud and polish to bring cc's back up, right?
With .030 bore, felpro .050 gasket, -0.009 deck height, flat top hyper eutectic pistons, 58cc chamber, static CR is 9.43 which is great.
W/victor .045 gasket, CR is 9.55
With .040 bore (in case I need to bore), felpro .050, -0.009 deck height, flat top pistons, 58cc chamber, static CR is 9.47. W/ victor 0.45 gasket, CR is 9.60
A little unshrouding may happen with the new valves so I may end up perfectly at 58cc. Factory chamber is 56-58 so hopefully it hasn't been decked much in its life. Worst case is to unshroud and polish to bring cc's back up, right?
Your calculations are correct.
The best thing to do is measure the actual deck height.
If you have a 12" caliper, measure from the top of the main bore to the block deck and add 1/2 the main bore diameter.
You certainly can increase the chamber volume by unshrouding the valves.
I like to bolt the head to the bare block and scribe the cylinder bore circle on the head surface for a guideline.
Do not use the head gasket for template.
The best thing to do is measure the actual deck height.
If you have a 12" caliper, measure from the top of the main bore to the block deck and add 1/2 the main bore diameter.
You certainly can increase the chamber volume by unshrouding the valves.
I like to bolt the head to the bare block and scribe the cylinder bore circle on the head surface for a guideline.
Do not use the head gasket for template.
Original Std. Ford 200 Pistons were a 1.511 C. H. generally a stock 200 short block (all years) will have a piston to deck height of .019. With the stock steel shim head gasket this gives a very good Quench Distance of .041. The regular oversize replacement 200 Pistons have a 1.50 C.H and puts them down the hole at .030.
Looks like your block might be a little thicker deck if you still have the OEM pistons. In any case if you decide to use those Australian Pistons and they stuck up .009 above the deck using a FelPro .050 head gasket will get you right back at a .041 Quench Distance again it should work out excellent. The Victor Reniz head gasket would also work well for a little tighter Quench making it even better at .035. Best of luck
Looks like your block might be a little thicker deck if you still have the OEM pistons. In any case if you decide to use those Australian Pistons and they stuck up .009 above the deck using a FelPro .050 head gasket will get you right back at a .041 Quench Distance again it should work out excellent. The Victor Reniz head gasket would also work well for a little tighter Quench making it even better at .035. Best of luck
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Yes!
Very good info in this thread. I, for one. Came up with the same conclusion, Ausie pistons from Summit. And the Toyota valves! What a Great idé! Got my Exhaust valves to Day, from a company in US, made in China and sold in Sweden.. Well traveled valves i say. Just have to ream the guides to fit, and open up the seats a tiny bit. I'll folow this closely.
Very good info in this thread. I, for one. Came up with the same conclusion, Ausie pistons from Summit. And the Toyota valves! What a Great idé! Got my Exhaust valves to Day, from a company in US, made in China and sold in Sweden.. Well traveled valves i say. Just have to ream the guides to fit, and open up the seats a tiny bit. I'll folow this closely.
What does that measurement give me? Centerline to deck? I don't follow.
Of course don't use the head gasket lol. Good to know that is a good option. We're still picking valves at this point. He's taking his time which is fine b/c I'm broke
Quench distance is important, i was thinking about that actually how the aussie pistons would help that a lot. Why is it then that milling the head screws up the quench, but having the piston come up higher is good?
Kevin hasn't gotten back to me yet about my dynamic compression ratios, but if I use the victor, with 56cc chambers, -.009 deck height, I end up with a static CR of like 9.7. Thats a hot ass motor haha. Hopefully the dynamic won't be too rough then.
If I were doing a new guides, Toyota valves would be great. But I did some conversions and 8mm is smaller than 11/32, so I have to find a larger valve. RIP.Yes!
Very good info in this thread. I, for one. Came up with the same conclusion, Ausie pistons from Summit. And the Toyota valves! What a Great idé! Got my Exhaust valves to Day, from a company in US, made in China and sold in Sweden.. Well traveled valves i say. Just have to ream the guides to fit, and open up the seats a tiny bit. I'll folow this closely.
Anyhow, how's your cut off triple weber log going? I would love to use triple webers but the budget definitely does not allow for that at this time, especially with having to rebuild the short block now.
It gives you a line to follow when unshrouding the valves, so the chamber walls do not go beyond the cylinder walls
Here is a chamber that I unshrouded for larger valves using the cylinder bore scribe line.
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Ryan, Bubba is only talking about the change from the thin shim and the thicker new gaskets, milling the head will not change quench, only volume.
Mr 9's measurement will give you the, as ford machined the block and not the theoretical block height. Well that is what I took from it.
Mr 9's measurement will give you the, as ford machined the block and not the theoretical block height. Well that is what I took from it.
I have the block, crank and rods at the machine shop, awaiting my Ausie +. 030 flattops and a crank grind, was allready
0.10 under. Head is ready for new valves, just got the exhaust, waiting for the intakes to araive. then have to flow it before desiding on camshaft, springs and retainers. Would like some konical ones, we'll see.
0.10 under. Head is ready for new valves, just got the exhaust, waiting for the intakes to araive. then have to flow it before desiding on camshaft, springs and retainers. Would like some konical ones, we'll see.
