• Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-

high milage 347s

  • Thread starter Thread starter Tanus
  • Start date Start date Dec 26, 2009

Tanus

New Member
Dec 11, 2009
847
1
0
A to the Z
Dec 26, 2009
#1
  • Dec 26, 2009
  • #1
hear alot negative talk about the 347s, wrist pin intersecting the oil rings, causing blow-by. Long stroke putting pressure on the cylinder walls causing premature wear.

so anybody have, or know of 347s with lots of miles on them?

notice more 331s on this site than 347s, so is the general consinsus that the extra 16ci's not worth it?
 

5.0Droptop

...all those nights we shared, and you're a dude??
Special Agent Mukity-Muck Whats in Charge Round Here
May 15, 2002
1,785
1,130
233
Indiana
Dec 26, 2009
#2
  • Dec 26, 2009
  • #2
I had a 347 built with the best of parts. It was using alot of oil by 20k
 

Gearbanger 101

Straight Outta Locash
20+ Year Stangneter
Aug 10, 2002
9,457
1,377
234
Ontario, Canada
Dec 26, 2009
#3
  • Dec 26, 2009
  • #3
I was under the impression that it was only the early 347-stroker kits that intersected the wrist pin with the oil ring. The later kits were suposed to have cured that problem?

As for cylinder wall side load....yes, this is true, but exactly how many miles you're going to see out of an engine varies. Your driving habits will have a lot to do with things I would imagine.

In any case, don't count on getting the same kind of life span out of a 347 that you would the stock 302.
 

Grn92LX

Fidanza Man!
Founding Member
Jan 14, 2001
6,819
64
129
New York
Dec 27, 2009
#4
  • Dec 27, 2009
  • #4
The pin through the oil ring has ZERO to do with any oil usage. If its using oil at that low mileage, it wasn't built right, something mechanically is wrong or it wasn't broken in properly.
 

85_SS_302_Coupe

it sucks (I know) to be on the receiving end
15 Year Member
Nov 11, 2003
6,945
1,598
223
Northern KY
Dec 30, 2009
#5
  • Dec 30, 2009
  • #5
Posted via Mobile Device hp typically comes at a price. I'd say no matter who builds an engine or what parts are used it'll never last as long as a factory 302. What you have to remember is how much fun it is while it lasts. Plus engines can be rebuilt so it's not the end of the world.
 

89stang1

Stroked and Juiced
10 Year Member
Nov 5, 2008
730
234
74
nj
Dec 30, 2009
#6
  • Dec 30, 2009
  • #6
Gearbanger 101 said:
I was under the impression that it was only the early 347-stroker kits that intersected the wrist pin with the oil ring. The later kits were suposed to have cured that problem?

As for cylinder wall side load....yes, this is true, but exactly how many miles you're going to see out of an engine varies. Your driving habits will have a lot to do with things I would imagine.

In any case, don't count on getting the same kind of life span out of a 347 that you would the stock 302.
Click to expand...

+1.......thats been fixed for years now.................but cylinder pressure is more with a 347 than 331 heres and old thread on the subject very informative
http://www.stangnet.com/mustang-forums/719569-302-stroker-information.html
 

FastDriver

I was uncomfortably high & wearing a helmet
SN Certified Technician
Sep 5, 2001
6,109
2,725
224
Vass, NC
Dec 31, 2009
#7
  • Dec 31, 2009
  • #7
wrist pins still intersect the oil ring land with a 5.4" rod. Some people report having no problems with their 347. If it's built right...
 

Tanus

New Member
Dec 11, 2009
847
1
0
A to the Z
Dec 31, 2009
#8
  • Dec 31, 2009
  • #8
89stang1 said:
+1.......thats been fixed for years now.................but cylinder pressure is more with a 347 than 331 heres and old thread on the subject very informative
http://www.stangnet.com/mustang-forums/719569-302-stroker-information.html
Click to expand...
great thread, I have a extra 5.0 block, dont know if I wanna go the 347 route or just go with the 351 stroked like 396. IDK. 306 I have now I built in like 02, and ran like 20 20lbs bottles of nos through, still runs strong but Id like a upgrade.

I can get a mexican 302 also, what are these worth? say with stock bore.
 

89stang1

Stroked and Juiced
10 Year Member
Nov 5, 2008
730
234
74
nj
Dec 31, 2009
#9
  • Dec 31, 2009
  • #9
FastDriver said:
wrist pins still intersect the oil ring land with a 5.4" rod. Some people report having no problems with their 347. If it's built right...
Click to expand...

Hey Chris.........................yeah i agree so many things have been changed to fix a non isuue for a well built engine, shorter rods different design pistons really i never saw a ford that didnt burn a little oil sooner or later. Theres some chevy strokers with the same oil ring wrist pin location problem ............u hardly ever hear about. I have more oil problems with my dam intake collecting oil i wish i new about the small baffle letting oil thru PCV into intake problem i wouda put a bigger baffle in..... problem comes and goes.
 

Shaolin Crane

Banned
Oct 6, 2008
2,627
7
0
Kommiefornia
Dec 31, 2009
#10
  • Dec 31, 2009
  • #10
Gearbanger 101 said:
I was under the impression that it was only the early 347-stroker kits that intersected the wrist pin with the oil ring. The later kits were suposed to have cured that problem?

As for cylinder wall side load....yes, this is true, but exactly how many miles you're going to see out of an engine varies. Your driving habits will have a lot to do with things I would imagine.

In any case, don't count on getting the same kind of life span out of a 347 that you would the stock 302.
Click to expand...
Probe, scat and other piston maufacturers have cured the side wall problem too, they all offset the rod mounting point in the piston to get it to where it have the same angle ratio that the stock stroke stuff has, only downside to that is, you need to clearance the block almost 1.5" to get the rods to keep from knocking
 
S

SVTFreak

Member
Jan 11, 2006
106
6
18
Dec 31, 2009
#11
  • Dec 31, 2009
  • #11
I built one 7 years ago that i used longer rods to lower the sidewall pressure, moving the wrist pin higher in the piston. I also moved the rings up on the piston (yes, custom pistons are expensive) putting them where i wanted them to keep the oil ring out of the wrist pin. Im not sure it is worth the expense there but since i was havingg them made anyway... The block clearance wasnt too bad although a bit more than normal. Also blockcreted the block and used a main girdle.

The motor now has 17000ish on it with no problems.
 

88blowngt

New Member
Jun 29, 2009
68
0
0
Dover, Delaware
Dec 31, 2009
#12
  • Dec 31, 2009
  • #12
89stang1 said:
Hey Chris.........................yeah i agree so many things have been changed to fix a non isuue for a well built engine, shorter rods different design pistons really i never saw a ford that didnt burn a little oil sooner or later. Theres some chevy strokers with the same oil ring wrist pin location problem ............u hardly ever hear about. I have more oil problems with my dam intake collecting oil i wish i new about the small baffle letting oil thru PCV into intake problem i wouda put a bigger baffle in..... problem comes and goes.
Click to expand...

89, have you thought about an oil seperator?
 

89stang1

Stroked and Juiced
10 Year Member
Nov 5, 2008
730
234
74
nj
Dec 31, 2009
#13
  • Dec 31, 2009
  • #13
88blowngt said:
89, have you thought about an oil seperator?
Click to expand...

yeah i heard its a pain having to empty often, really mine is not that bad as long as it dont get worse im ok just gotta hammer down every now and then to blow the oil out
 

Tanus

New Member
Dec 11, 2009
847
1
0
A to the Z
Dec 31, 2009
#14
  • Dec 31, 2009
  • #14
89stang1 said:
I have more oil problems with my dam intake collecting oil i wish i new about the small baffle letting oil thru PCV into intake problem i wouda put a bigger baffle in..... problem comes and goes.
Click to expand...
I used to have the problem too, fixed it by using exhaust scavenging to suck out the pressure. works way better.exhaust smokes a little but no big deal.
 
You must log in or register to reply here.

Similar threads

E
Finished my Fox Hydroboost Install - Tips
  • Engineer Duane
  • Apr 9, 2025
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
4
Views
1K
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- May 5, 2025
Engineer Duane
E
ANY HELP IS APPRECIATED 1988 mustang gt
  • Foxbody1988
  • Dec 23, 2019
  • Fox 5.0 Mustang Tech
  • 2
Replies
23
Views
5K
Fox 5.0 Mustang Tech Dec 28, 2019
General karthief
And now for something different: Forced Induction Crankcase ventilation systems.
  • CarMichael Angelo
  • Aug 17, 2018
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
4
Views
2K
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Aug 17, 2018
Steel1
2002 3.8 A/C clutch and Cooling Fan not working after fuel pump change
  • laughsarefree
  • Sep 14, 2018
  • 1996 - 2004 SN95 Mustang -General/Talk-
Replies
17
Views
4K
1996 - 2004 SN95 Mustang -General/Talk- Sep 15, 2018
Noobz347
Fuel New fuel pump no start
  • General karthief
  • Nov 21, 2018
  • Fox 5.0 Mustang Tech
Replies
10
Views
2K
Fox 5.0 Mustang Tech Dec 19, 2018
fun331
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?