Chuck's Engine Build

[cdigerlando]

Well, I finally got all of my parts back from the machine shop. My cylinder clearance are on the big side, due to some cylinder wall corrosion that I had. I'm running about 4 thousands, which should be fine.

I tried to be slick like Mike and cage the bearings, but my readings were not very repeatable, even with less precision than his instruments, so I decided to just check everything with plastigage. My rod bearings all hit dead nuts on 1.5 thousands clearance. This is with swain coated ACL tri metal race bearings. My main bearings varied from 2 - 1.5 thousands. My runout on the last bearing was less than 1 thousanth, so with that I'm going to go ahead and assemble this thing. I will probably start nights on Monday. I should definitelly have the long block assembled by the end of next weekend. I need to do a bit more clean up of the water jackets, and port the oil pump entry hole to improve oil flow, since there are no aftermarket pumps greater than our stock 12 mm pump for subaru motors. I'm also going to order a new oil pan since the cleaning process did a job on the interior paint, and I'd rather not take a chance on problems associated with paint flakes in my oil.

I'll take pictures along the way and post them. I'm sure it will not be as precise as mikes motor, but there are a few differences. I semi-closed the deck for one, but I have not had any porting or port matching of the heads done. I also have not done any coatings, other than my bearings. I'm running a bit more clearance on my main bearings, but using a coated ACL tri metal race bearing instead of Mike's aluminum bearings. I think my bearings will be able to handle a lot of power, but may not have the longevity of the Mike's bearings. I'm also installing cometic head gaskets instead of OEM. Hopefully they will hold up well. I'm thinking of using copper spray to help with sealing, as I've seen a few nasioc builders doing this.

If anyone is interested in using the machine shop I used, let me know. He is pretty busy, but said that he would be interested in doing another motor some time in the future.

[Boxersix]

Originally Posted by cdigerlando

I'm thinking of using copper spray to help with sealing, as I've seen a few nasioc builders doing this.

Don't use the copper spray......instead go buy a can of Mopar(dodge chrysler) head gasket sealant. It is specially formulated for MLS steel gaskets and works well with all after market. Sprays on as a tacky clear yellow fluid but thins out very quickly and displaces with torque. More importantly it goes on even.

The problem with the copper spray is it's uneven layer and inability to thin out. If you let it stand too long you'll end up with uneven layers of sealant which over time can blow out and leak. Best not to use it.

I've built hundreds of motors in my life and the Mopar stuff is excellent.

[cdigerlando]

Originally Posted by Boxersix

Don't use the copper spray......instead go buy a can of Mopar(dodge chrysler) head gasket sealant. It is specially formulated for MLS steel gaskets and works well with all after market. Sprays on as a tacky clear yellow fluid but thins out very quickly and displaces with torque. More importantly it goes on even.

The problem with the copper spray is it's uneven layer and inability to thin out. If you let it stand too long you'll end up with uneven layers of sealant which over time can blow out and leak. Best not to use it.

I've built hundreds of motors in my life and the Mopar stuff is excellent.

Thanks I'll give that a try. Where do you get it?

[longassname]

Hey Chuck,

I know you have some of the 1st gen ARP head studs. The short studs in that "kit," the ones that go under the cam gears, need to be torqued in otherwise they will rub on the cam gears. I think I put all my studs in at 13 ft lbs. Anyway, pay attention and make sure you have the studs under the cam gears in as far as they will go. I changed the specs with ARP after my build so in the future the short studs will be 6.70 instead of 6.75".

When I did the write up on my build I forgot to mention the process of breaking in the studs. With the gasket set up you are talking about you will want to do this with your old gaskets before you install your heads for real with your new gaskets. With your old head gaskets go through the whole torque sequence and then fully loosen the nuts up and do it again. Do that 5 times. That breaks the studs in so that from then on the clamping force associated with a given torque will be reliable and repeatable.

I suggest you not use maximum torque for the fastners. You'll have to check my post in my engine build thread but I think I settled on 73 ft lbs of torque. Because of the differences in thermal expansion between the aluminum block/heads and the arp2000 studs it's best to leave yourself as generous room for stretch before reaching yield as possible while still getting the clamping force you want. If you troque them all the way up to close to yield and then thermal expansion stretches them past yield then they stay stretched, your head gasket goes bad, and you start running around trying new gaskets and closing decks etc not realizing the studs are just toasted.

[longassname]

Chuck,

How much less than .001 run out do you have? You only have run out on 7 and not 6? What # journals are you spinning the crank on when checking for run out?

For your build you should really get zero observable run out. Factory specs will let you run something crazy like 14 tens run out but that kind of stuff has no place in a performance build. You want to be able to run high loads at high rpms with complete confidence.

[longassname]

Chuck,

Get your piston skirts coated to close up those sidewall clearances. You should be able to get 2 tens or 4 tens thick coating. With those measurements get the 4 tens coating. With 4 thou sidewall clearance you will get skirt slap when the engine is cold. The 4 tens coating will narrow that down to .0032 sidewall clearance which will run much more smoothly and quietly.

[cdigerlando]

Originally Posted by longassname

Chuck,

How much less than .001 run out do you have? You only have run out on 7 and not 6? What # journals are you spinning the crank on when checking for run out?

For your build you should really get zero observable run out. Factory specs will let you run something crazy like 14 tens run out but that kind of stuff has no place in a performance build. You want to be able to run high loads at high rpms with complete confidence.

I only checked 7 and 1, running bearings on 1 and 5. My equipment I had access to would not fit between the crank lobes. Ran about 7.5 tens on the runout. 0 of course on 1. I was pretty happy to just be able to check 7, but it would have been nice to be able to check journal 3.

[cdigerlando]

Originally Posted by longassname

Chuck,

Get your piston skirts coated to close up those sidewall clearances. You should be able to get 2 tens or 4 tens thick coating. With those measurements get the 4 tens coating. With 4 thou sidewall clearance you will get skirt slap when the engine is cold. The 4 tens coating will narrow that down to .0032 sidewall clearance which will run much more smoothly and quietly.

I spoke with CP already about coatings, but they do not recommend them even though it is done all the time Hopefully I don't get much slap. I know that can be an issue with these forged pistons and wider clearances. CP recommends .0035 correct?

[cdigerlando]

Originally Posted by longassname

Hey Chuck,

I know you have some of the 1st gen ARP head studs. The short studs in that "kit," the ones that go under the cam gears, need to be torqued in otherwise they will rub on the cam gears. I think I put all my studs in at 13 ft lbs. Anyway, pay attention and make sure you have the studs under the cam gears in as far as they will go. I changed the specs with ARP after my build so in the future the short studs will be 6.70 instead of 6.75".

When I did the write up on my build I forgot to mention the process of breaking in the studs. With the gasket set up you are talking about you will want to do this with your old gaskets before you install your heads for real with your new gaskets. With your old head gaskets go through the whole torque sequence and then fully loosen the nuts up and do it again. Do that 5 times. That breaks the studs in so that from then on the clamping force associated with a given torque will be reliable and repeatable.

I suggest you not use maximum torque for the fastners. You'll have to check my post in my engine build thread but I think I settled on 73 ft lbs of torque. Because of the differences in thermal expansion between the aluminum block/heads and the arp2000 studs it's best to leave yourself as generous room for stretch before reaching yield as possible while still getting the clamping force you want. If you troque them all the way up to close to yield and then thermal expansion stretches them past yield then they stay stretched, your head gasket goes bad, and you start running around trying new gaskets and closing decks etc not realizing the studs are just toasted.

I have the 6.75" in studs. I'll give the break in a try with my old gaskets. Thanks for the advice. I think that ARP recommends approx 73 ft lbs on these studs.

[longassname]

Sounds like you need to get yourself a good dial guage base set. You definitely need to put in the time to find out where that bend is and get it corrected. Don't use the way it is now..you will regret it.

Originally Posted by cdigerlando

I only checked 7 and 1, running bearings on 1 and 5. My equipment I had access to would not fit between the crank lobes. Ran about 7.5 tens on the runout. 0 of course on 1. I was pretty happy to just be able to check 7, but it would have been nice to be able to check journal 3.

[longassname]

The guys who build impreza engines get audible skirt slap on a cold engine with 4 thou sidewall clearance so I'm confident you will as well. It's up to you but I'd get the skirt coating.

Originally Posted by cdigerlando

I spoke with CP already about coatings, but they do not recommend them even though it is done all the time Hopefully I don't get much slap. I know that can be an issue with these forged pistons and wider clearances. CP recommends .0035 correct?

[SVXRide]

chuck,
plenty of shops out there that will coat the skirts. I've used ThermalTech in Virginia for my intake and exhaust pieces.
-Bill

[longassname]

http://business.listings.ebay.com/In...istingItemList


There's the Ebay section to find a base set for a dial gage so you can check your crank correctly. Do yourself a favor and don't get a brand new made in china set for fifty cents. They don't work. Get yourself a quality set made a couple or few decades ago. I like nsk japan but there are some good US brands too. Starrett and Mitutoyo are the mainline brands today. An antique Brown and Sharp or NSK Japan set will be higher quality.

[cdigerlando]

Mike:

How much bend did you have in the crank when your shop was done maching it? The dial guage I used is very accurate, it just doesn't read down to more than .25 thousands, and is difficult to position between the lobes. At less than half the allowable bend on the last journal I'm sure it will be fine. My original bearings looked very clean.

Don't forget too, I didn't coat the tops of my pistons, so they should heat up and expand fairly quickly. After speaking to CP I decided against it, so here I am. My machine shop guy has installed many CP pistons, in fact he doesn't like installing anything but, and did not think it is a problem, so at this point I'm going to trust his judgement. Besides a little piston slap at startup doesn't get me too worried.

[SVXRide]

Originally Posted by cdigerlando

Mike:

Besides a little piston slap at startup doesn't get me too worried.

Okay, so everyone is going to remember that Chuck said this a month or so from now
-Bill