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Mystery solved, stopped crying.

  • Thread starter Thread starter 78SilvAnniv
  • Start date Start date
Again, do consider having your machinist check angle/fit of intake to heads. And … have a Q&A w/ speed shop where heads came from … regarding any surfacing/milling/mismatch/ new v. rebuilt v. “seconds

Heidi,

I forgot to add that the heads that we put on that 406 were brand new DART heads. Soooooo, Since you have it all apart it would be wise just to be sure and check this dimension during re-assembly. As for the cam, if you call competition cams in Memphis, they can put some data you need to provide in the computer and come up with the best bang for your buck. Pertinient data would include engine size, trans type, vehicle weight, tire size, rear end ratio, RPM range, use of vehicle, carburation, modifications to engine, etc. Lunati can do the same and they are also in Memphis. Careful with going to big as then you will have to have a stall convertor if you are running an Automatic. And yes you can get the manifold gasket out of whack when you install the intake but I think you should make sure that your angle is correct on the mating surfaces or it will just do it again. Remember, if you don't have time to fix it right the first time--When will you have time to do it over?? Good lUck.

Randy:w
 
Too many things to reply to, and I may forgets some...

My belief is the heads are brand new, but I'll ask the speed shop when I go in today for the gaskets.
I recall during the first put-together Kenny set the manifold on the heads, heads bolted to block, and everything appeared to line up correctly angle-wise, even without gaskets in between. The gaskets would have made for a proper fit.
Somehow, the intake gaskets slipped sideways and we bolted through to the side of the bolt holes of the gasket. Will think of a way to affix the gasket before setting the manifold on, to prevent shifting.
Jack, as to the pictures...#4 spark plug had just been cleaned, so it showed no crud on it, just a light coat of oil. It was the worst looking plug for gunked crud before it was cleaned. The piston and bearings are not a pic of #4. The #4 piston still looks like silvery aluminum. All other pistons look like the one shown, dark with those markings.
I have a parts shopping list and I'll be heading into town...
Heidi
 
When Kenny put the manifold on with the gskts did he start each of the bolts in each hole and then snug them down in sequence (X pattern)? If not then this will also cause the gasket to squirm. After you have snug the bolts down, Start at the center bolts and work your way along the manifold on both sides in an X pattern. Tighten them down a little at a time. Finally use a torque wrench and tighten to final torgue setting on last go around of tightening. Do this in same X pattern sequence. The purpose is to draw the mainfold down to the gskt and head evenly. Maybe all that happened was someone got in a hurry and tightened the bolts down from front to back all on one side and then did the other side the same way. Also I always throw away the front and rear rubber block gskts and use the Copper high Temp RTV silicone. Apply a 1/8 inch bead to the block and let it set for a few minutes till it skins. Have your intake gskts placed on the head when you do this and the silicone bead applied across the block to the V area at the head will hold them in place during the manifold install. Just a suggestion.

Randy:w
 
I watched Kenny. He did everything like you said. We even threw away the end gaskets and did the silicone bead thing.
Heidi
 
Heidi,

Sounds like you will be back in the driver's seat before you know it. Break it in gently, but enjoy the new found power.
Good luck!:w
Pete.
 
78SilvAnniv said:
My belief is the heads are brand new, but I'll ask the speed shop when I go in today for the gaskets.Jack, as to the pictures...#4 spark plug had just been cleaned, so it showed no crud on it, just a light coat of oil. It was the worst looking plug for gunked crud before it was cleaned. The piston and bearings are not a pic of #4. The #4 piston still looks like silvery aluminum. All other pistons look like the one shown, dark with those markings.
I have a parts shopping list and I'll be heading into town...
Heidi
Heidi & Kenny:
The oil-gunk on piston in pic is normal for the 7 older pistons. Like you say ... maybe the intake gasket just slipped upon assembly. On the intake gasket, I put silicone all around the water ports (both side of gasket) and stick it to the head. G'luck.
JACK:gap
 
We have the black FelPro gaskets with blue lines around the ports, can we do the silicone thing on those kind of gaskets? We also bought some 3M yellow adhesive to dot next to the bolt holes to affix the gasket to the heads for no shifting when we place the manifold.

Looks like assembly will be today. I need to give bobchad a call...we canceled assembling the engine with him because it looked like we were going to have a problem with the rings. My pistons are shallow, not deep groove and I didn't know if the set we ordered last night (and came in this am) would work.

I'll keep everyone posted.
Heidi
 
So I take it that the intake gasket is accually two pieces plus the end rubber gaskets and not the valley pan type one piece gasket and two rubber end gaskets?
 
What a day!

JRMaroon came over today to assist with assembly. We were unable to reach bobchad until late afternoon, but he is planning on coming over tomorrow and JRMaroon is also planning on coming over again.

What a great group of friends we have made on CAC. Pizza for lunch tomorrow!

Bobchad missed installing the cam and crank. Tomorrow Kenny will be plasti-guage measuring the bearing gaps (I think that's what he's doing) and installing 7 of our pistons and one head. We have decided to replace the Napa piston we purchased this winter with a GM piston that will match the other 7 original to the block. I think they are "Badger" brand.

We found that the Napa piston is a deep groove while the original remaining 7 are shallow groove. It took us for-ev-er to find the correct rings with the tolerances that fell into spec. Kenny was ready to pull what remains of his hair out due to his dealings with the parts-guys!
The parts guys are usually really helpful with me... (batting eyelashes) :D

We'll let you know about our progress tomorrow.
Heidi
 
7 pistons were in when I had to leave with Kenny cleaning the head for the odd numbered bank of pistons and Jeff waiting to help him put it on. My job was to put the rings on the pistons and orient them. I could almost take up a second job. :L

I think Heidi is going to post some pictures later.

Heidi, Kenny was telling me that he hadn't obtained the oil pan gasket yet and I was telling him about this 1 piece unit that Chevy High Performance wrote about. It supposedly replaces a 4 piece stock gasket and seals much better. Manufactured by Felpro. It's more expensive than the stock gasket but they claim it works better reducing leaks.
 
How Heidi got her groove back

Heidi & Kenny:
We're using the FelPro P/N OS34510T one-piece pan gasket ... and using one in circle track race car ... works good for us. If it does leak ... it's a heck of a lot easier deal with than 4-pc. I pay about $23 for 1-pc ... versus $33 at Summit. You should NOT use any silicone or glue with the 1-pc ... EXCEPT ... for a tiny dab at the 4 corners. Since you hardly use any silicone ... gasket surfaces must be SUPER clean with 1-pc.

Yes ... you can smear silicone on black fp intake gasket that already has the blue lines.

:duhShame on me :Buttslap ... for not considering your Goodwrench might've come with shallow (~0.165") oil ring groove and low tension expander ... rather than the more conventional deeper (~0.200") oil ring groove. And ... it seems you did have a ring problem on #4 after all. When y'all recycled the old rings (with shallow, low tension expander) onto the replacement piston ... you had about 0.035" too much back clearance on the oil ring ... probably made for lousy oil control.
JACK:gap
 
What is the difference and/or purpose of deep and shallow oil ring grooves?
Are they used in specific applications?
Heidi
 
78SilvAnniv said:
What is the difference and/or purpose of deep and shallow oil ring grooves? Are they used in specific applications? Heidi
Heidi:

Simply my take ... but I understand that shallower grooves and accompanying rings with reduced radial wall thickness can conform to cylinder walls more closely ... providing improved compression (improved fuel efficiency) and oil control ... and doing so with reduced tangential ring tension (less friction-more power-more efficient). Not all but many newer vehicles (most makes) use pistons that have shallow grooves. Some just on oil groove, some top comp & oil grooves. For example, most 90 thru 97 vettes probably came with shallow oil groove.

JACK:gap
 
Thank you, we were curious. We had such a difficult time purchasing the correct oil rings and the people we asked at the parts counters didn't have any explanations for us...
Heidi
 
The latest in this soap opera!

Today is the day that we find out if GM has the correct piston for my 1997 crate engine. I sure hope it's correct, because if it isn't...Kenny may actually kill someone.

Over the weekend, we decided to not re-install the Napa piston we purchased to replace the dented #4, and instead order a correct replacement from GM. Monday I drove to my local dealership (Maxie Price where Rick Daniels used to work) and brought my dented #4, boxed in the Napa piston box.

Well...I explained about the piston but as I was speaking, the parts guy saw the Clevite box made up his mind that it was an aftermarket product and was not helpful. He did give me a few website addys and a phone number to check.
I drove home, surfed and made some calls. Eventually I was directed to Dickey-Scoggins in Texas who came up with a part number for me and advised me to order it from my local dealership. Which I did.

The piston arrived Tuesday and was certainly not the correct one. It didn't look anything like my piston. The parts guy called the 'vette mechanic from the back, and he picked up both pistons and looked at their faces and said "Wrong compression ratios. Won't work." He then looked inside my piston, saw the casting number and told the parts guy to call the parts reference department and cross reference me a part number for my piston.
(Which is what he could have done Monday if he'd have listened to me!)

So, that piston will arrive today. I sure hope they match and that I don't receive the same kind of piston I saw Tuesday. D-S had the same casting number I gave them as this parts guy called in...

The parts guy said the correct piston costs $150. We were flabbergasted! What makes this one piston so special!? (special because I need it) For what it would cost to buy 8 GM pistons, we could purchase an entire GM crate longblock! Besides that...for $150 we can purchase 8 pistons from any auto parts suplier and still have money left over!
Kenny was livid by the time we left. :mad

The parts guy felt bad for not correctly helping me on Monday and offered to sell us this piston for cost, which is $90. Still expenesive, but our only other option is to remove the driver-side head, its' gasket, 1-7 pistons w/ new rings and lose the time Kenny spent adjusting those valves and the #2,6&8 pistons to replace all pistons at the same time so all pistons match in mass, weight and type.
So...I really hope the piston that arrives today is correct.
Heidi
 
Heidi,

Call The Last Detail. They know what they are doing and depending on which of the GM companies manufactured it, they have gotten me stuff for less than what GM was willing to sell it to me for.

Bob
 
78SilvAnniv said:
my dented #4, boxed in the Napa piston box.

the parts guy saw the Clevite box made up his mind that it was an aftermarket product and was not helpful.Heidi
Maybe on another day ... when nerves aren't so frayed ... maybe engage the parts man in idle conversation ... ask if he knows who makes the "genuine GM pistons, bearings, rings etc ... maybe he'll know that none are actually made by GM ... but by a host of suppliers ... of which clevite is a major OE supplier. GM ain't perfect ... I KNOW from direct experience as recent as past fall ... GM corporate ordering OE parts from my client (an established, respected OE supplier) when GM did not have latest revision of their own dam drawing (& GM couldn't find it either) ... They were *****in' about parts not made to print ... hell parts were made to latest rev level ... too bad GM'd lost their ORIGINAL and copies of latest rev level ... they didn't even have a log/history of what rev levels had existed ... they ended up getting a copy of my client's most recent print ... It was at latest rev level ... I liked to _hit a brick over that one!

BTW ... part numbers usually do NOT change as their drawings' rev levels do change. Soooo ... because of above snafu ... I recommend that when the piston arrives ... have it looked over real good ... and have a caliper handy and check the width and depths of the grooves ... who knows what rev level drawing the piston you get was built to comply with.

Chin up H&K ... "this too shall pass."
JACK:gap
 

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