347 eating oil
- Thread starter aleborjas
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88Stangboy
Banned
Does the stroker kit push the wrist pin up into the rings? What did he set his ring gap at, or what was it set at, do you know? How many miles on the engine?
88Stangboy
Banned
most guys i know set them at about 0.24, but that is a little wide. That wont help his oiling problem any though.
A properly built 347 will use no oil just like a 306/331.
Did the engine have blowby which would push the dipstick out of its holder? If the dipstick was not pushed out, then the intake may be sucking oil and vaporizing it. another potential problem could be the PCV valve.
He should have done a leakdown test to determine how much compression he is losing . A good motor has between 2%-10% leakdown, anymore than 10% time for a refresh.
Also a leakdown test will not determine if the piston scraper rings are stuck or frozen. The piston scraper ring scrapes the oil off the cylinder wall and if they r not functioning properly u will burn oil.
another oil burning problem is bad valve guides or valve seals. I have heard that using teflon valve seals on a street motor causes excessive oil consumption.
Did the engine have blowby which would push the dipstick out of its holder? If the dipstick was not pushed out, then the intake may be sucking oil and vaporizing it. another potential problem could be the PCV valve.
He should have done a leakdown test to determine how much compression he is losing . A good motor has between 2%-10% leakdown, anymore than 10% time for a refresh.
Also a leakdown test will not determine if the piston scraper rings are stuck or frozen. The piston scraper ring scrapes the oil off the cylinder wall and if they r not functioning properly u will burn oil.
another oil burning problem is bad valve guides or valve seals. I have heard that using teflon valve seals on a street motor causes excessive oil consumption.
88Stangboy
Banned
I agree with 304billet, do a compression test, and iv'e also heard about those teflon guides. Mainly on the exhause side, due to the excessive heat its exposed to.
But actually it isn't ideal to have to the pin up into the ring pack, primarily because it puts the wrist pin closer to the compression deck and it is exposed to much more heat up there. And most pistons that put the wrist pin up there also have a thinner compression deck thickness. My friends and i usually try to stay away from stroker kits that push the pin up into the rings. Mainly because they run lots of nitrous and lots of boost.
But actually it isn't ideal to have to the pin up into the ring pack, primarily because it puts the wrist pin closer to the compression deck and it is exposed to much more heat up there. And most pistons that put the wrist pin up there also have a thinner compression deck thickness. My friends and i usually try to stay away from stroker kits that push the pin up into the rings. Mainly because they run lots of nitrous and lots of boost.
I read a article in muscle mustang and fast ford mag that said by 10000 miles 347 will usally start using oil. they say nature of the beast. they article was trying to show that a 331 stroker kit was a much better kit for street applications. in this case however i would agree that the oil consumption is excessive. I would inspect my intake. remove the tb and see how much oil is actually being diverted to the intake via the egr. You didn't mention if he as any oil leaks.304billet said:
Nick302
New Member
86bluecobra said:
Not this again.
Clue #1 MM&FF
Lemme guess, it was the DSS article. My guess is they weren't selling enough 331's
88Stangboy
Banned
i say if your going to build a 347...just build a 351. More cubes, put your aluminum heads on it and you. Just never made any sense to me personally. (save me the lecture) I've riden and driven many of my friends 347 cars and some of their nicely built 351's. I can tell no difference in the torque, excelleration. One of my friends Steven has a 347 in his 95GT and its pretty stout, but he's gotten eaten up by some 306's, so i guess it's just what you put into it 
Personally though, i would just run a 351W roller block with some nice heads and a good cam.
Personally though, i would just run a 351W roller block with some nice heads and a good cam.
Nick302
New Member
Nick302
New Member
That's a whole 'nother discussion. Personally I'd rather stick with a 347. Stock hood, stock brackets etc, no need for 2k dollar heads and all that. People will only know you have a 347 if you tell them.
88Stangboy
Banned
and they're going to notice a 351? Not to much externally to set off any alarms. I just don't see spending $1,600 for a half decent stroker kit and it only increases torque marginally. Sorry. Most everyone puts a cowl on their car anyhow. Lowering engine brackets are a bad idea on any engine anyhow because it off sets your pinion angle in your rear end. Most of my buddies take some early seventies 351 heads and have them ported/flowbenched, no 2K heads here, just opened up and gasket matched, etc. bigger valves, flow awsome, mybe not that light, but the power they make offsets any weight anyhow. Most 347's i know make around 375ish-430ish hp, depending on heads and cam. Most 351's i know make around 450ish-550ish and they mybe spent $500 more and thats only because of the special lifters you need. And if you want to grow up and play with the big boys, you can easily stroke a 351 for about the same price you can a 302 and make much more power and torque. Sorry, its pretty clear the route i would go personally.
.24" ???
Use the specific ring manufactors specs BUT gap the second ring .002"-.004" larger, especially if it is a power adder motor. There are a lot to ring gaps, depending on application, tolerances, materials and usage. 99% of the time you do not have to touch the oil rings out of the box....
Wrist Pin in the ring is no big deal....internet myth.
304billet, mentioned some good stuff above
Use the specific ring manufactors specs BUT gap the second ring .002"-.004" larger, especially if it is a power adder motor. There are a lot to ring gaps, depending on application, tolerances, materials and usage. 99% of the time you do not have to touch the oil rings out of the box....
Wrist Pin in the ring is no big deal....internet myth.
304billet, mentioned some good stuff above
88Stangboy
Banned
they run .24 because there more of a racing engine, they run stuff a little looser. They use nitrous and boost so they just leave a little more room incase they run a little lean or get some detonation it wont close the gap up. For the street that is a little more than the usual .18-.20ish.
Back to the Original Question
Is this car efi? I would love to help as I have had some similar issues, and have found several ways of minimizing oil consumption.
If it is efi you need to first look at the inside of the intake, and all hoses leading to it from the crankcase. The VC/TB hose and the pcv hose are routes for oil to enter the intake. Anther possibility is the lower intake manifold gasket slid down during installation, resulting in a vac leak common to the lifter valley.
If you pull the vc/tb hose it should be bone dry. If it is wet with oil, then that is most likely the problem. Removing the vc baffle will cause this.
If the vc/tb hose checks out then pull the inlet tube from the tb. At one point mine was so bad that oil was dripping out of the tb when I pulled the inlet tube. Open up the throttle blade and look inside the intake; you may find puddles of oil accumulating there.
This is all assuming that the oil is being consumed, and that there are no gasket leaks. Can blue smoke be induced by hitting the throttle?
Hope some of this helps,
jason
aleborjas said:
Is this car efi? I would love to help as I have had some similar issues, and have found several ways of minimizing oil consumption.
If it is efi you need to first look at the inside of the intake, and all hoses leading to it from the crankcase. The VC/TB hose and the pcv hose are routes for oil to enter the intake. Anther possibility is the lower intake manifold gasket slid down during installation, resulting in a vac leak common to the lifter valley.
If you pull the vc/tb hose it should be bone dry. If it is wet with oil, then that is most likely the problem. Removing the vc baffle will cause this.
If the vc/tb hose checks out then pull the inlet tube from the tb. At one point mine was so bad that oil was dripping out of the tb when I pulled the inlet tube. Open up the throttle blade and look inside the intake; you may find puddles of oil accumulating there.
This is all assuming that the oil is being consumed, and that there are no gasket leaks. Can blue smoke be induced by hitting the throttle?
Hope some of this helps,
jason
