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...I decided to do the .003" p/w clearance since some of the coating will wear off so that should end up somewhere within the range.
That will be ample, no matter what you end up doing with respect to power level. Are you going to use the OEM ring set, or go with CP's rings?

Also, have you read the NASIOC discussions on ring gaps? Interesting stuff - what surprises me is how tight Cosworth sets their gaps. No one else (that I know of) has had the courage to try theirs at Cosy's numbers, but ya gotta figure Cosy has a fairly good idea of what they're doing. :lol:
 

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Discussion Starter #22
That will be ample, no matter what you end up doing with respect to power level. Are you going to use the OEM ring set, or go with CP's rings?

Also, have you read the NASIOC discussions on ring gaps? Interesting stuff - what surprises me is how tight Cosworth sets their gaps. No one else (that I know of) has had the courage to try theirs at Cosy's numbers, but ya gotta figure Cosy has a fairly good idea of what they're doing. :lol:
I'm using the CP ring set. This is was derived with the .0035 recommendation from CP minus .0005 for the side skirt coating. I just don't want to be too loose when the initial coating wears off.
 

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...I just don't want to be too loose when the initial coating wears off.
Good, because it will. I personally think guys make a big mistake when they set their clearance to the coating, and not to the bare piston underneath.

Give us a shout when you determine your ring gaps, OK? I'm doing a little research.
 

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Discussion Starter #24
Mike, CP tech support gave me ring gap numbers: top ring .025, 2nd .028, oiling ring .15, and also recommended due to the hardness of the 1st ring the cylinders must have a rough hone. I had my machinist call Mike to get the proper ra (roughness average) numbers and what grit honing stones are required.
 

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Cool. Ask you builder/machinist about using quick-seal on the cylinder walls at assembly. Some guys aren't, but I'm a real believer in that stuff.
 

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Discussion Starter #27 (Edited)
After a google search, hows quick seal made by Total Seal?

This product is made by Total seal. There's also alot of info about cylinder honing and of course piston rings, gaps, etc.

From Total Seal's FAQ TechPage

Quickseat is our patented dry film cylinder wall assembly lube. It’s
quite unique in that it is a dry lube this helps to prevent glazing of the
rings from the over use of assembly oil. It also provides outstanding
lubrication during the critical initial start up period helping to prevent
ring scuffing and cylinder wall burnishing.
 

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Discussion Starter #28
After reading that Total seal faq page about cylinder honing I'm glad I had my machinist talk to CP's tech support to get the right honing requirements. Now I'm wondering if I should have considered using Total Seal's piston rings. Now I want to find out more info on the quick seal product and will possibly have my builder use it.
 

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Discussion Starter #31
Got my BC 272 cams and Supertech dual valve spring kit. I was thinking of just replacing the exhaust valves with inconel Supertech valves and using the stock intake valves. I'll replace the intake valves if I can sell some of my parts though.
 

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Discussion Starter #32
Well I'm going to order the Supertech black nitride intake valves and the inconel exhaust valves. Should I stay standard size or go 1mm larger? No port and polish and will going 1mm shift me to the right more? Will there be a noticeable difference with going 1mm larger?
 

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Discussion Starter #33 (Edited)
I just picked up my block today after a 3 wk wait. I had John Edwards talk to CP Piston's tech support to get the right ra numbers for their rings. Cosworth's tech support also recommended an ra of between 20 or lower for the deck surface to have their head gasket seal correctly. So this was the goal when resurfacing the top of the block deck. John also checked the mains for straightness. The crank was sent out to have a .001" clearance on the rod journals. He also balanced the whole rotational assembly to 0.5 gram.

Here's some vids of machinist I used, John Edwards from Costa Mesa R & D:

Honing an STI block
YouTube - Subaru STi Block Honing

Here's another vid from John Edwards of R & D Costa Mesa resurfacing a Subaru SVX block with sleeves:
YouTube - Subaru SVX Sleeved Block Resurfacing

Here's another of his custom 6 qt Subaru oil pan:
YouTube - Subaru Aluminum Oil Pan, etc...
 

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Mike, CP tech support gave me ring gap numbers: top ring .025, 2nd .028, oiling ring .15, and also recommended due to the hardness of the 1st ring the cylinders must have a rough hone. I had my machinist call Mike to get the proper ra (roughness average) numbers and what grit honing stones are required.
That's what I gapped mine to (I was worried that it was too large of a gap) and after removing one head (I installed a comp ring upside down and it was smoking, had to fix that) and re-installing a new ring set on the piston, I noticed the walls with my rough hone were nice and smooth (the rings seated pretty quickly) and the car no longer burned oil. I have ~250 miles on the motor (plus a bunch of idling and revving) and it has a tad bit of slap when cold, but goes away once warmed up. Seems like it is going to be fine. These are ceramic coated CP dropins.
 

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Discussion Starter #36
Stick with the TS buddy..

Any idea on the cost of your motor?
Once the motor's done I just slap the vf36 back on until AVO comes out with their ts. They came out with a new exhaust housing cast and was sent to the machine shop. Hopefully it'll be out soon. I believe it's already up towards $6500 usd and I don't have everything I want. I'm just trying to spend on parts that wouldn't require pulling the motor again.
 

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Discussion Starter #38
those videos are awesome! I think I just found my new engine builder. :)
He's highly recommended. John has taught this field for 10 yrs, published a book called the "auto dictionary", and has several other publications.

My mechanic broke the plastic cam gear exhaust sproket on the passenger side even with the right tools. Can that be replaced with a metal gear off of another 2.5 na subie motor?
 

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He's highly recommended. John has taught this field for 10 yrs, published a book called the "auto dictionary", and has several other publications.

My mechanic broke the plastic cam gear exhaust sproket on the passenger side even with the right tools. Can that be replaced with a metal gear off of another 2.5 na subie motor?
I wouldn't do it, even if it fit.
 
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