DEAD 4.7 stroker! HELP!

Performance mods and Advanced Stroker discussion.
crustodd2
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Re: DEAD 4.7 stroker! HELP!

Post by crustodd2 »

OK, so I talked to a guy at KB and he said that, yes the 2618 944 castings is BAD. Wrong alloy for the application. He'll give me a BIG discount on the 2229c SilvoLite hypereutectics. Does anyone know what the dish volume is on that piston? I'm trying to figure out if I can take a little more out if necessary, so I can still use my head that has .050 taken off.

Anyone?
crustodd2
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Re: DEAD 4.7 stroker! HELP!

Post by crustodd2 »

Silver,
Well, I guess I though that the KB's were a 9.0:1 piston, so when I found out that they were 9.5:1, I assumed that pushed it up another .5:1 Either way, too much compression. The cam was broken in by me EXACTLY as the Lunati instructions said. Since I'd lost the Comp. cam with somebody else doin' the brake in, I wanted to make sure. As the machinist commented, usually a bad brake in kills the cam in about the first 1000 miles. This one went 15K and I used ZDDP additive and Brad Penn oil starting at about 2500 miles. I used the additive the whole time though, even with the dino oil as the engine was breaking in, or as it seems, just breaking :brickwall: The pistons were noisy ALL year on cold start and when the engine had cooled way down. I live in Oregon, so it isn't "cold" here very often. The piston casting are 2731's as it turns out, not the 2618's. Do you know if these were the incorrect alloy mix as well? Why would the oil be pumpin' out the CCV system that much? How would it be gettin' to the combustion chambers?

Thanks,
Todd
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SilverXJ
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Re: DEAD 4.7 stroker! HELP!

Post by SilverXJ »

I think KB specs the pistons .020" down in the hole and that is where they get the 9.0:1 from. Still, 9.77 shouldn't be too much for pump gas. Mine is 9.62 an I can run on premium with a good AFR with out pinging. If I ran it rich I could get away with mid-grade. Which Brad Penn were you using. Most of their oil is partial synthetic. Brad Penn should already come with enough ZDDP. I have heard that too much ZDDP will also wear parts excessively.

As for the piston alloy, I never heard of 2731 and Google didn't bring up anything relevant. Is that a number they gave you or the number on the side of the piston?

Did you do any modifications to the valve cover such as remove the baffles? The ccv can suck up engine oil and deliver it into the intake manifold where it will then enter the cylinder. I believe someone here had that problem when they removed their baffle.
crustodd2
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Re: DEAD 4.7 stroker! HELP!

Post by crustodd2 »

Hey Dino,
I talked with Silver for a long while last eve. to try and figure out the issues I'm having. I am leaning towards your suggestion of the new /rebuilt long block. I'm wondering though. The combustion chamber in my head is 58CC's. Silver concluded this is about what stock is. I had my head milled down about .054 total to fix an earlier suspected warpage and then to get the CC volume down from 64CC's that it started at. This was to get it to match the 58CC's suggested on the calculator. An error perhaps of me not clearly understanding the math. Then I thought I needed to deck the block to zero to deal with the quench. So now I'm wondering which of the hypereutectic piston I can get that will allow my to reuse this head, dish an extra amount to drop the compression to around 9.0:1, and then allow me to deck the block to get the quench correct. Does a lower compression ratio negate the need for the tighter quench? What about the "poor man", which I now am, build with more dish on the pistons and decked block to get the quench into the .040"'s? and the dual pattern stocker cam? Do I need a new dizzy drive gear with the new cam? Do I need to get the cam from the dealer?
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Re: DEAD 4.7 stroker! HELP!

Post by 4.whoa »

Check the FAQ section under pistons. There are part#'s with their cc#'s. Its better to use a new gear with a new cam, however some have gotten away without doing so- but not me :(
-Russ

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Re: DEAD 4.7 stroker! HELP!

Post by Cheromaniac »

crustodd2 wrote:Hey Dino,
I talked with Silver for a long while last eve. to try and figure out the issues I'm having. I am leaning towards your suggestion of the new /rebuilt long block. I'm wondering though. The combustion chamber in my head is 58CC's. Silver concluded this is about what stock is. I had my head milled down about .054 total to fix an earlier suspected warpage and then to get the CC volume down from 64CC's that it started at. This was to get it to match the 58CC's suggested on the calculator. An error perhaps of me not clearly understanding the math. Then I thought I needed to deck the block to zero to deal with the quench. So now I'm wondering which of the hypereutectic piston I can get that will allow my to reuse this head, dish an extra amount to drop the compression to around 9.0:1, and then allow me to deck the block to get the quench correct. Does a lower compression ratio negate the need for the tighter quench? What about the "poor man", which I now am, build with more dish on the pistons and decked block to get the quench into the .040"'s? and the dual pattern stocker cam? Do I need a new dizzy drive gear with the new cam? Do I need to get the cam from the dealer?

Ok, if the CC's in your head are 58cc then you can reuse it but you'll need stock valve springs if you're going to use the stock cam. You'll still need a replacement short block so you can have that overbored +0.030" and use Silvolite 2229 pistons on 4.2 rods. If you zero deck the block and use a 0.043" head gasket for a nice, tight quench, the piston dishes can be expanded from 11.5cc (that's off the shelf) to 25cc for an SCR of 9.3, which will allow you to run 87 octane.
Don't forget that you'll probably need ~0.100" shorter pushrods than stock if you deck ~0.050" from the block to get the clearance to zero.
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crustodd2
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Re: DEAD 4.7 stroker! HELP!

Post by crustodd2 »

Hey Dino,
That sounds pretty good. I'm a little confused on the piston dish, though. I read a post of yours on NAXJA from 2005 that said the 677cp's, which are the same piston as the 2229 pistons, have a 17.5CC dish. Has that changed. Also, it looks like a stock, new cam from the dealer is about $400.00 for cam and lifters! That's pretty steep! Should I use the factory cam to insure the correct hardness of the parts? Glen, at BullTear, said he thinks the oil AND the variation of the correct hardness of the parts is whats killin' cams. Again, which year of cam do I need? Are the later model cams dual pattern and will they fit the '91-'95 block? What about the used distributor and a NEW cam wearing together? Problem?

Thanks,
Todd
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Re: DEAD 4.7 stroker! HELP!

Post by 92tank »

this might be a long shot, but if you are getting a new block (junkyard right?) why dont you just use that cam?
crustodd2
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Re: DEAD 4.7 stroker! HELP!

Post by crustodd2 »

Hey 92tank,
The cam is toast. One of the lobs is almost wiped off and the front cam bearing, at the least, is worn pretty bad. No hope there.
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Re: DEAD 4.7 stroker! HELP!

Post by 6TIME »

Can you recall the seat/open pressures that your springs were installed at? Bummer the whole deal turned bad!
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Re: DEAD 4.7 stroker! HELP!

Post by Cheromaniac »

crustodd2 wrote:Hey Dino,
That sounds pretty good. I'm a little confused on the piston dish, though. I read a post of yours on NAXJA from 2005 that said the 677cp's, which are the same piston as the 2229 pistons, have a 17.5CC dish. Has that changed. The 677CP's do have a 17.5cc dish but they're entirely different pistons from the Silvolite 2229's.
Also, it looks like a stock, new cam from the dealer is about $400.00 for cam and lifters! That's pretty steep! You're not kidding. You can get a new stock replacement cam from rockauto.com or from NAPA.
Should I use the factory cam to insure the correct hardness of the parts? Glen, at BullTear, said he thinks the oil AND the variation of the correct hardness of the parts is whats killin' cams. I agree, especially with the latter.
Again, which year of cam do I need? Preferably '87-'95.
Are the later model cams dual pattern and will they fit the '91-'95 block? The '96-'98 cams will but the '99+cams won't.
What about the used distributor and a NEW cam wearing together? Problem? With a new cam it'll be adviseable but not essential to use a new distributor gear.
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Re: DEAD 4.7 stroker! HELP!

Post by crustodd2 »

Hey 6time,
The pressures were 110 intake, 115 exhaust. 270 open pressure on both. Yeah, I just was emailing Dino and commenting that I wish I'd stayed more conservative on the build from the get go. To be honest as a DD, I drove it pretty mellow most of the time anyway. Since I'm one of the "mechanically challenged" members here, I had the work done for me and tried to assemble the right part list and what I thought was the right and necessary machine work. I think I got a bit carried away and maybe relied on the benefit of water/meth. on the compression issue. I'm to embarrassed now to reveal the total, but I've built this engine twice now goin' on a third time. You can imagine the UGLY and EXCESSIVE cost here. Suffice to say, I could have had HESCO build me a VERY nice turbo engine at this point. I'm not kidding..

I guess what I can get out of this is- NOOBS, listen to the senior members here, their experience and knowledge could save you a PILE O' Cash. If's it's a DD, be sensible and conservative. It's an OLD engine design. It has a reputation for goin' high miles, but not when you stress it. Unless you're building a play-toy and you've got plenty of cash AND patience, use the factory cams. Less stress, longer life, more time drivin' less time sittin'

Thanks,

T`
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Re: DEAD 4.7 stroker! HELP!

Post by Cheromaniac »

crustodd2 wrote:The pressures were 110 intake, 115 exhaust. 270 open pressure on both. Yeah, I just was emailing Dino and commenting that I wish I'd stayed more conservative on the build from the get go.
Those are not excessive pressures by any means for a performance cam but I do question the quality of the surface hardening treatment on some of the aftermarket flat tappet cams that were sold in the past few years. Cam companies were quick to hide behind the excuse of low ZDDP oil being the problem but I'm not so sure.
We all live and learn and some of us, especially the "seniors", have learnt the hard way and seen hard-earned cash go up in smoke. Don't be embarassed Todd. You're in good company so just chalk it down to experience. :)
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crustodd2
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Re: DEAD 4.7 stroker! HELP!

Post by crustodd2 »

Well Dino, I was kinda' counting killin' the first cam when it was just a 4.0 as the only necessary "experience" :frustrated: I didn't know this was a "multiple choice test" :lol: What is really aggravating is how many guys have built their engines with meticulous preparation and still had them take a dive. I wonder if anyone has a high-mile HESCO that they'd tell us about? Does Bernie and co. know some secrets that the rest of us haven't figured out? Again, it seems like the more conservative valve train is the key. That's where I'm goin'.

Thanks,
Todd
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Re: DEAD 4.7 stroker! HELP!

Post by SilverXJ »

Hesco's valve pressures are right around what you have. I think you might have had an oil contamination issue. It would explain why all the parts failed aside from the piston noise that was always there. Possibly a sticking injector or two.
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