340 Engine Shake

toolmanmike

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No I'm at .040 over now. I guess I got scared when I looked down the coolant passages and saw the rust. But I got to have the professionals give the final doag before jumping the gun. It's going in tomorrow.
You should be good then. Sconic check and bore .060. Freshen up as needed. Oh, I wouldn't use a Comp Cam or lifters.
 

AJ/FormS

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What's wrong with using the earlier, smaller cam? Put some solid lifters on it and call it done; you'll never have to worry about an annoying tic again, cuz you'll have 16 of 'em.... lol.
Plus the earlier closing intake will net you more CCP and a stronger bottom end to replace that which you lost, when you left the automatic behind.
Plus, a wider power-band to cover that 3+1 gear spread.
Plus the smaller cam will like the overdrive more.
Plus the less overlap/earlier closing intake valve, will make the EFI happier.

How much of the "ugliness" in the cylinders is pits and how much is just staining? What I mean is maybe a couple of thou is all you need to clean it up.
Hypers are usually installed pretty tight.... like .002. Maybe you can get away with .003/.004.
My KB 107 hypers are running at .0045 clearance, and the engine makes great power, with file-fit plasma-moly rings.. .... jus saying.
I would rock that 340, with looser skirts. and file-fit rings.

I would forget about roller lifters, too; I haven't been able to kill my Hughes HE3038AL cam since 2004. Like RRR says; "rollers are over-rated." and IMO, especially hydros.
My Hughes 3037 is 276/286/110 and 230/237@.050 with lifts of .549/.571 @1.6 arms. I used their best Hydros at the time. I used to rev it to 7000/7200 all the time. I ran them at about .5 turn preload. I run a 750DP.

The thing is, with a 4-speed, your idle speed and gears will determine your minimum road speed. With 26.6"tires, 4.10s and a 3.09 low gear, your roadspeed maths out to 6.25 mph @1000rpm; 700 is still 4.4mph and too fast to walk alongside. To parade it, you need to get down to a max of 3.5 mph, which is 560rpm. To run down there, your Idle-Timing is gonna need to be down around 5* advanced.
My 367 will idle down there all day with the 750DP, but it wasn't easy getting it to do that, with the 230* cam. I can't see it being any easier with the Fi-tech. Nor with what is now, a 350 cubic inch short-stroke engine.
It was even better with my previous HE2430AL cam,
270/276/110, 223/230@.050 and .538/.549@1.6arms. I remember that cam with much fondness.

BTW; it's not the tight cam centerline per se that the EFI doesn't like; rather, it is the large amount of overlap, and especially the low vacuum signal of the late-closing intake that bothers her.
Solid lifters let you run a lil more cam for the same vacuum signal, and part of the "more cam" can be in the overlap. But in my case, running 3.55 gears, the 230 cam really is out of it's element, and the only thing that saves my combo is the 180psi CCP. The previous 223* cam was much happier about the 3.55s.

So lets look at the numbers.
First, the current 230* cam, in at 107; , then the previous 223* cam in at 105*.
the cam events are;
>>276 intake/114 compression/105 power/286 exhaust/61overlap/Ica of 66*
>>270 intake/120 compression/107 power/276 exhaust/53overlap/Ica of 60*
Notice that the 223 cam makes 120 verses 114 compression. this translates to a CCP increase of about 10psi, from 177 to 187, in my case. This is a big increase and it affects the Idle vacuum a lot.
Next notice the Power-cycle has gone from 105 to 107, not much difference here, but the engine has gained 2* more time to extract energy from the expanding gasses increasing the potential for fuel economy.
Finally, notice that overlap has fallen 8* from 61 to 53; so yeah this cam makes a lil less power, but with a 4-speed you'll be hard pressed to feel it in the first two gears, and I'm half-way thru third before I get it, and only because I previously had a 292/292/108 cam lol. See; my new power peak with the 230 cam, is not 200rpm higher, (say 5200 verses 5000 with the 223cam), but at WOT, she hits 65mph at 5500 at the top of Second gear bang on the power peak. So yeah, she's no slouch, but she ain't fighting the wind yet. With the 223 cam, she was already on the downside of the power curve, but it hardly mattered cuz the tires were usually still spinning.......
Now, because I had CCP to spare, I ran that 223 cam a hair retarded to move the power up a hair and in at 109* I got this;
>>270 intake/116 compression/111 Power/276exhaust/53overlap/ Ica of 64*
Notice I lost 4* of compression, but gained that same 4* now in Power. I just upped the Scr to 11.3 (from 11.0) to get the CCP back.
But that 111* of Power-extraction made a huge increase in Steady-State fuel economy.
After I got the new 230cam tuned up, I sorely missed that 223* cam. I have been waiting since 2004 for that 230 flat-tappet cam to expire......... so I can go back at least to a 223cam, but more likely a 218, cuz I know I can get hiway mpgs well over 30 with double-overdrive........ with a spreadbore carb, and geared for 65= ~1500.
A roller cam won't touch that because of the loooooooooong clearance ramps required to get those heavy lifters in motion. Everybody talks about how the roller cams can be faster at mid lifts and over the nose, but totally ignore the slow-start problem. Like RRR said; "rollers are over-rated". Ima going with a solid flat-tappet. The solids have clearance ramps too, and usually a lil slower than a hydro, but not as slow as a roller, and the solids are lightweight, rev to the moon, and are trouble-free.
I'm just thinking out loud.
 
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mgoblue9798

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Pics of the crank journal. Rod bearings look just like the main bearings.

View attachment 1715981941

View attachment 1715981942

For a street engine I would polish the crank and run it.

If the block cylinder walls don't show any signs of blueing from heat or a thin spot, I would at least have it checked out at a machine shop.

Even if it has to go bigger than .060 over, as long as the block is sonic tested and checks out there are pistons available for it made for the large bore R block engines.
 

plumkrazee70

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UPDATE:

Block crank pistons and rods dropped at the machine shop. It cannot go 60 over only because 20,000 will not clean it up. He's going to have the owner look it over but his gut was to sleeve it. He did not see anything wrong with the crank, but he hasn't measured just a visual. He's going to check the line on the block to the crank and magnaflex the block.

He also wasn't a bit concerned at all with the rust in the water jackets.

He said no doubt water got into the cylinder somehow and given the fact that the motor sat a while even though it was sealed up with parts in bagged he said it doesn't take much moisture for something like that to happen and letting it sit.
 

plumkrazee70

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I'll know more next week, but if it can be sleeved and it's cost-effective I'll keep the 340 and bring all my parts to him and plan out a little build with what I have.
 

mgoblue9798

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UPDATE:

Block crank pistons and rods dropped at the machine shop. It cannot go 60 over only because 20,000 will not clean it up. He's going to have the owner look it over but his gut was to sleeve it. He did not see anything wrong with the crank, but he hasn't measured just a visual. He's going to check the line on the block to the crank and magnaflex the block.

He also wasn't a bit concerned at all with the rust in the water jackets.

He said no doubt water got into the cylinder somehow and given the fact that the motor sat a while even though it was sealed up with parts in bagged he said it doesn't take much moisture for something like that to happen and letting it sit.

If you live in a humid place like me in Atlanta, unless the parts are soaking in oil or coated with grease they will rust. Humidity causes condensation inside the bag. I use STP on cylinder bores if I know it will be a bit before the engine will be running.

@Plumcrazee70, since you got the raw end of the deal with this motor and if you are on a tight budget because of that, I have a brand new 214 224 @ .050 .444 intake .466 exh lift hydraulic flat tappet elgin cam on the shelf I will give it to you if you need it to get back up and running. It is an old school cam that was very popular back in the day for a street engine 340/360.
 
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plumkrazee70

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If you live in a humid place like me in Atlanta, unless the parts are soaking in oil or coated with grease they will rust. Humidity causes condensation inside the bag. I use STP on cylinder bores if I know it will be a bit before the engine will be running.

@Plumcrazee70, since you got the raw end of the deal with this motor and if you are on a tight budget because of that, I have a brand new 214 224 @ .050 .444 intake .466 exh lift hydraulic flat tappet elgin cam on the shelf I will give it to you if you need it to get back up and running. It is an old school cam that was very popular back in the day for a street engine 340/360.

Thank you. I think the cam is ok. Will know next week, I think. I'll keep you updated.
 

plumkrazee70

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UPDATE:

I met with the machinist today. I have three options:

1. Keep the 340.
- The block will need to be sleeved to re use. $1,200.
- The cam is fine (needs new lifters)
- The crank is fine
- The rods, pistons and rings are fine

2. Find another 340
- All hard parts can be re used
- Machine work and balance
- Cost of a new block?

3. Start over with LA360
- Machinist has block & crank $250
- Rough estimate of machine work and parts (re using my rods) $1,600 (including new flywheel and balancer)

My gut is telling me to start over with a 360, only because finding a 340 would be near impossible at a reasonable price.

Remember this is a slant 6 car originally, so not married to a 340. I can sell my pistons and crank to help offset the cost.
 

plumkrazee70

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So I'm wondering if there is a 340 out there for a reasonable price.

Still don't know what caused the metal, but the cam is perfect. So that is good.
 

MoparMike1974

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1. Keep the 340.
- The block will need to be sleeved to re use. $1,200.

By the time you find another block and do the machine work you will be right around the same money. Sleeve it and get it back to standard bore.

3. Start over with LA360
- Machinist has block & crank $250
- Rough estimate of machine work and parts (re using my rods) $1,600 (including new flywheel and balancer)

Economical option if you are not matching numbers. Yeah, stroke it while your at it :)
 

plumkrazee70

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1. Keep the 340.
- The block will need to be sleeved to re use. $1,200.

By the time you find another block and do the machine work you will be right around the same money. Sleeve it and get it back to standard bore.

3. Start over with LA360
- Machinist has block & crank $250
- Rough estimate of machine work and parts (re using my rods) $1,600 (including new flywheel and balancer)

Economical option if you are not matching numbers. Yeah, stroke it while your at it :)

I agree on the 340 (either way) gotta do my due diligence for the wife.

I would just pull the trigger on the 360,.but justify the cost of the stroker. I just want a mild street car.
 

Rat Bastid

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Just doesn't seem cost effective, I can do his 360 for almost the same dollars as just sleeving the 340.


Your thinking with you wallet and not your head. No offense.

Done correctly, that sleeved block will make more power and live longer than any other block.

Don’t step over donuts to pick up dog turds. And I wouldn’t sleeve it back to standard. I’d sleeve it to .060 over and buy a thick sleeve to get it there.
 

plumkrazee70

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Your thinking with you wallet and not your head. No offense.

Done correctly, that sleeved block will make more power and live longer than any other block.

Don’t step over donuts to pick up dog turds. And I wouldn’t sleeve it back to standard. I’d sleeve it to .060 over and buy a thick sleeve to get it there.

I hear you, however, I'm not interested in a ton of power. I just want a nice street car. I bought this car in 2013 and have only driven it a total of 250 miles maybe. My wife is upset and doesn't understand how a rebuilt motor could get water in it from just sitting, when her 78 elcamino has sat for almost 15 years and it fires right up and drives out of the barn and it's none stock original.

I get her frustration and she doesn't want to spend a ton more.
 

JDMopar

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Get the 360 block from the machine shop and buy a set of bearing spacers so you can use your rotating assembly back. I did not read back far enough to see what bore size pistons you have, but if you bore the 360 to 4.040 you could use stock 340 pistons. There was a NICE set of 10.5-1 factory 340 pistons for sale here cheap a week or so ago. Good luck to you. Check the thread linked below to get the info on the bearing spacers.
Homemade 340 ### | For A Bodies Only Mopar Forum
 

Rat Bastid

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I hear you, however, I'm not interested in a ton of power. I just want a nice street car. I bought this car in 2013 and have only driven it a total of 250 miles maybe. My wife is upset and doesn't understand how a rebuilt motor could get water in it from just sitting, when her 78 elcamino has sat for almost 15 years and it fires right up and drives out of the barn and it's none stock original.

I get her frustration and she doesn't want to spend a ton more.


I’m not talking about turning it into a race engine. I’m talking about ring seal and such.

There is no way you’ll ever get your wife to understand. Trying to do so will frustrate the hell out of her and piss you off.

Fix it correctly and move on. You’ll never explain why what you are doing is as important as a new lawn mover or a stove or some **** like that.
 

plumkrazee70

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Get the 360 block from the machine shop and buy a set of bearing spacers so you can use your rotating assembly back. I did not read back far enough to see what bore size pistons you have, but if you bore the 360 to 4.040 you could use stock 340 pistons. There was a NICE set of 10.5-1 factory 340 pistons for sale here cheap a week or so ago. Good luck to you. Check the thread linked below to get the info on the bearing spacers.
Homemade 340 ### | For A Bodies Only Mopar Forum

Interesting. I'll bring it up to him about the bearing spacers.
Get the 360 block from the machine shop and buy a set of bearing spacers so you can use your rotating assembly back. I did not read back far enough to see what bore size pistons you have, but if you bore the 360 to 4.040 you could use stock 340 pistons. There was a NICE set of 10.5-1 factory 340 pistons for sale here cheap a week or so ago. Good luck to you. Check the thread linked below to get the info on the bearing spacers.
Homemade 340 ### | For A Bodies Only Mopar Forum

The 360 bore is 4.00, it would have to go .080 to use my 340 pistons.

340 bore is 4.04 and .040 makes it 4.080. he has a crank for the 360.
 

plumkrazee70

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I’m not talking about turning it into a race engine. I’m talking about ring seal and such.

There is no way you’ll ever get your wife to understand. Trying to do so will frustrate the hell out of her and piss you off.

Fix it correctly and move on. You’ll never explain why what you are doing is as important as a new lawn mover or a stove or some **** like that.

You don't know my wife. She is very analytical and understands far more than most women when it comes to cars.
 
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