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Discussion Starter #1
Hey guys, so I'm refreshing my drivetrain, rear end and trans are done now it's on to the motor. It's a 289 already at .040 over with an unknown number of miles. It's getting tired, low old pressure and oil leaks. I'd really like to rebuild it for the originality but at 040 over I'm not sure it's worth putting money into. It has stock heads on it with an Edelbrock performer cam I installed 10+ years ago so it's nothing special. What do you guys think I should do? Get a roller 5.0 and be done with it or try and rebuild the 289? Thanks.
 

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Havoc, you should rebuild the 289. The early 289 block is stonger than the 5.0, being .040 is NO PROBLEM, you cango out to .060 without fear, and the 65 289 heads are desirable for chamber size and lack of lumps in the exhaust port. You COULD get a slightly nicer intake, but you don't have to. Do you have headers ? Want them ? Street driving ? I'll throw some part numbers at you later this evening if you're interested. LSG
 

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Discussion Starter #5
How many miles on it since it’s last rebuild?

Tear it down and give it a good inspection.
It may not need to be bored.
Maybe just a hone with new rings.
No idea on the mileage it was in the car when I bought it 12 years ago. I did replace one of the heads last year and noticed a decent groove at the top of the cylinders when I had it apart.
 

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Discussion Starter #6
Havoc, you should rebuild the 289. The early 289 block is stonger than the 5.0, being .040 is NO PROBLEM, you cango out to .060 without fear, and the 65 289 heads are desirable for chamber size and lack of lumps in the exhaust port. You COULD get a slightly nicer intake, but you don't have to. Do you have headers ? Want them ? Street driving ? I'll throw some part numbers at you later this evening if you're interested. LSG
It has try y headers and 2.5 inch duals. Flow master mufflers I believe. Yeah it’s a street car doesn’t get raced or tracked. I’m actually pretty happy with my current power levels I just want a nice reliable motor we can cruise in.
 

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Havoc, it sounds like you'll need to bore then. The pistons you want are made by Silvolite, they're hypereutechtic aluminum with flattops and coated skirts. They're 1.605 tall and have 4 valve notches in the top, part 3010HC, in .060 over. Don't accept any substitutions. No other piston is as nice of a choice. There will be lots of places that will try and sell you a Silvolite 1177, don't accept those, they are .020 too short, you would lose compression, power, and economy, even though the 1177 is also flattopped. The rings you'll want are from Hastings, 2M139.060, these have a moly face on the top ring and are gentle on the bores and hold up well. While there are LOTS of choices for parts, 35 years of experience at an engine shop has taught me what works best, and what is most cost effective. There are other correct height pistons available, even from Silvolite, but the require expensive metric rings and offer no benefit. More later, Mrs LSG has dinner ready. LSG
 

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Start with a compression test. Maybe the rings are good and it smokes because of valve stem seals. If it needs a valve job, seals, a pile of gaskets then so be it. If it needs honed, or bored, no biggie. As above, choose quality parts. I pieced together a kit in 1993 for a .030 over 289 and it still kicks asz without smoking anything but the tires. The little 289s are awfully durable. I wouldn't hesitate to go to .040, .050, even .060 on mine to have that "original engine" smile.
 

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I had the same issue with mine. Keep my 289 or try the Exporer swap. In the end I kept the old 289. I'm picking it up tomorrow. Bored 0.60 over. I pulled the entire thing apart. Lots of fun! Also it lets you check out every journal and bearing yourself. If you can mic it all up and see how it looks.
 

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Discussion Starter #10
Thanks for the advice guys. I was under the impression 040 over was as far as a sbf could safely be taken and glad to hear first hand experience to the contrary. A compression test is on my to do list soon but it currently doesn’t burn any oil just leaks lol.
 

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You could have the block sonic tested to see how much meat is left to go 060 over. Having a cylinder or 2 sleeved is not a big deal these days.

To quote Woody from fordstrokers.com when I angst on going 40 over on my POS 331 "crate" engine bought from others "before anybody knew any better they just bored them 60 over and went racing"! I always look back to that discussion to put things in perspective.
 

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You could have the block sonic tested to see how much meat is left to go 060 over. Having a cylinder or 2 sleeved is not a big deal these days.

To quote Woody from fordstrokers.com when I angst on going 40 over on my POS 331 "crate" engine bought from others "before anybody knew any better they just bored them 60 over and went racing"! I always look back to that discussion to put things in perspective.
My machinist agrees fully about being able to go .060" over, however, we did a 289 .040" over that made it thought the cam break-in with no problems. Then cylinder 6 started leaking water via a pinhole. It's the only reason I throw a word of caution out.

Allen
 

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My machinist agrees fully about being able to go .060" over, however, we did a 289 .040" over that made it thought the cam break-in with no problems. Then cylinder 6 started leaking water via a pinhole. It's the only reason I throw a word of caution out.

Allen
I've had a dark spot on the bottom of the #1 cylinder bore since the last of a few times I've had the heads off my 331. I kinda know what that means. When I see white smoke... You can drive yourself crazy on what if's or just enjoy the ride.
 

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I had a scope in #6 and pressurized the radiator (water system) and saw a stream coming out. The piston had to be at the bottom to see it. My heart sunk.

Way past it now. Of course the next block only went .030" over so new pistons had to be bought, but you know the drill...

If I was the OP...I'd give it a run...

Allen
 

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I had a scope in #6 and pressurized the radiator (water system) and saw a stream coming out. The piston had to be at the bottom to see it. My heart sunk.

Way past it now. Of course the next block only went .030" over so new pistons had to be bought, but you know the drill...

If I was the OP...I'd give it a run...

Allen
I sadly know the drill. Anybody need a set of 30 over Probe 331 pistons with only 100 miles on them?
 

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Discussion Starter #17
Well if I decide to try and build the 289 I’ll have the machine shop look it over first and see what they think. I hate to spend a bunch of cash having them decide it’s not a good candidate that I could have put into a 5.0. My trans swap and rear end projects went WAY over budget so that’s a consideration too. Any recommendations for a cam that would give me a little more hp than the RV cam I have now but won’t be chocked out by stock heads?
 

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Well if I decide to try and build the 289 I’ll have the machine shop look it over first and see what they think. I hate to spend a bunch of cash having them decide it’s not a good candidate that I could have put into a 5.0. My trans swap and rear end projects went WAY over budget so that’s a consideration too. Any recommendations for a cam that would give me a little more hp than the RV cam I have now but won’t be chocked out by stock heads?
You're going to have to decide which engine you are using and then ask about cam specs. We can spend your money for you for sure, but better to pick a lane that you are going to go down first. Oh, and you will be over budget on the engine also... ;) :LOL:

I used Dema Elgin (Elgin Cams) for a custom cam on the go fast but it's all in how much power you are trying to make out of what engine...lots of variables!

Allen
 

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Discussion Starter #19
You're going to have to decide which engine you are using and then ask about cam specs. We can spend your money for you for sure, but better to pick a lane that you are going to go down first. Oh, and you will be over budget on the engine also... ;) :LOL:

I used Dema Elgin (Elgin Cams) for a custom cam on the go fast but it's all in how much power you are trying to make out of what engine...lots of variables!

Allen
Fair enough and yeah I know I’ll go over budget again. I guess I’ll find out how strong my marriage is lol.
 

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