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GT40P's & intake on 110K block - problems??

  • Thread starter Thread starter jaymac
  • Start date Start date May 18, 2005
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jaymac

New Member
Feb 18, 2004
995
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0
Northern Mass
May 18, 2005
#1
  • May 18, 2005
  • #1
This has already been addressed before, but now a mechanic has got me second guessing. He told me to wait to rebuild the bottom end before I bolt on my GT40P's (shaved .030, ported and polished) and intake. I know of alot of people on here, who've bolted them on stock high-mileage short blocks, so in reality, how worried should I be that I'm going to crack bearings or throw a rod, given the occasional 1320 visit?
Thanks again,
Jeremy
 

tmoss

Gettin Wired
Founding Member
Jun 28, 2001
7,153
32
128
Saint Louis, MO
May 18, 2005
#2
  • May 18, 2005
  • #2
My short block was in good shjape at 190,000 miles and I put the same stuff on mine.
 
8

89rdgt

New Member
Apr 24, 2004
103
0
0
Washington
May 18, 2005
#3
  • May 18, 2005
  • #3
i say slap em.. on and run her tell she dies. Your gonna find out its gonna be a while before she dies that is if you have been taken care of her.
 

twolo4u2c2

5 Year Member
Apr 10, 2003
330
6
29
reading, PA
May 18, 2005
#4
  • May 18, 2005
  • #4
Did the same thing........ran it another 50k after that. Now he same stuff is on my 347.
 

RYC CUKR

Founding Member
May 19, 2002
1,437
1
38
Orlando
May 18, 2005
#5
  • May 18, 2005
  • #5
I'm around 150k and put the P heads on bout 2 months ago. No probs so far. Already had tmoss ported GT40 on there for quite a while.
 

jaymac

New Member
Feb 18, 2004
995
0
0
Northern Mass
May 18, 2005
#6
  • May 18, 2005
  • #6
sounds like "all systems go " to me
 
M

mackey

Active Member
Jan 25, 2003
1,284
1
38
Beverly, Massachusetts
May 18, 2005
#7
  • May 18, 2005
  • #7
~120k miles. Trickflow H/C/I runs low 13s.
 

Aliate X

Member
May 9, 2005
602
1
18
Rockland NY
May 18, 2005
#8
  • May 18, 2005
  • #8
What if your engine is burning oil? Say 2 quarts every 2 or 3 weeks?
 

Curse

Member
Apr 8, 2004
791
2
16
El Paso, TX
May 18, 2005
#9
  • May 18, 2005
  • #9
Only problem I see you having is, no traction Good luck
 

5spd GT

"the 5.0 owns all"
Founding Member
Aug 7, 2002
9,516
6
99
Arkansas
May 18, 2005
#10
  • May 18, 2005
  • #10
Aliate X - That problem needs to be addressed...that is a pretty serious "burn". I would look into a rebuild. Most of the time with aftermarket heads your going to be running higher compression which will lead to a bit more oil burning...

To JayMac, I have 153k on my daily driver with h/c/i on my car. Been on there for 10k so far and no internal problems...I get better gas mileage before and I think it drives better to
 

Aliate X

Member
May 9, 2005
602
1
18
Rockland NY
May 19, 2005
#11
  • May 19, 2005
  • #11
5spd GT said:
Aliate X - That problem needs to be addressed...that is a pretty serious "burn". I would look into a rebuild. Most of the time with aftermarket heads your going to be running higher compression which will lead to a bit more oil burning...

To JayMac, I have 153k on my daily driver with h/c/i on my car. Been on there for 10k so far and no internal problems...I get better gas mileage before and I think it drives better to
Click to expand...


I was thinking of buying a stock 5.0 motor or something for a few hundred bucks and building my H/C/I motor outside of the car and make it 10:1 while Im at it. But then I think, for not much more I can have a 331 or something, so its very hard to figure out where to draw the line. Maybe just new pistons and bored out a little with 10:1 compression and a nice cam for now? What do you guys think?

Sorry to hijack btw.
 

maverick0716

Founding Member
Jan 12, 2002
3,924
0
56
Chilliwack, BC, Canada
May 19, 2005
#12
  • May 19, 2005
  • #12
I say you should rebuild it if you're burning oil like that. The only reason most of the other guys put parts like that on at such high mileage is because their engine doesn't burn oil and runs strong.....my personal opinion.
 

Aliate X

Member
May 9, 2005
602
1
18
Rockland NY
May 19, 2005
#13
  • May 19, 2005
  • #13
maverick0716 said:
I say you should rebuild it if you're burning oil like that. The only reason most of the other guys put parts like that on at such high mileage is because their engine doesn't burn oil and runs strong.....my personal opinion.
Click to expand...

Whats the most common cause of an engine burning oil? I cant imagine the engine was beat on bad, it was owned by a 60yr old man, and had all its schedueled tune ups. Ive owned it for only about 2 years.
 

tmoss

Gettin Wired
Founding Member
Jun 28, 2001
7,153
32
128
Saint Louis, MO
May 19, 2005
#14
  • May 19, 2005
  • #14
You need to find out why your loosing oil. Do a cranking compression test, a leak down test if you have the tool, and check the PCV system to make sure your not sucking oil into the combustion chambers that way.
 

jaymac

New Member
Feb 18, 2004
995
0
0
Northern Mass
May 19, 2005
#15
  • May 19, 2005
  • #15
all sounds encouraging to me!!
AliateX, you're sure you're "burning", not "leaking"? All oil pan, valve cover gaskets and rear main seal are good?
 

crazypete

All my crevices are greased.
Oct 22, 2004
930
4
18
Arlington, MA
May 19, 2005
#16
  • May 19, 2005
  • #16
140K and 40-ps no problem

AlienX: STOP RUNNING SYNTHETIC! If you burn 2 quarts every 2 weeks, I guarantee you're trying to run synthetic. Run 20w-50 dino oil and be amazed. I went from 1 quart every 100 miles to 1/2 quart per oilchange by switching away from synthetic.

If you're running dino oil and still burning.....definatley do the heads. The valve seals are a culprit for a lot of oil burning so the new heads will come with new seals and you'll kill 2 birds with one stone.
 

Aliate X

Member
May 9, 2005
602
1
18
Rockland NY
May 19, 2005
#17
  • May 19, 2005
  • #17
Im running 10w-30 right now, ill switch over to the 20-50 and see what happens....
 

5spd GT

"the 5.0 owns all"
Founding Member
Aug 7, 2002
9,516
6
99
Arkansas
May 19, 2005
#18
  • May 19, 2005
  • #18
crazypete - He needs to find out why he is burning oil before slapping heads on there and hoping it fixes it...just like putting a thicker oil in there, that is like a "band-aid" for the engine. He needs a fix...
 

crazypete

All my crevices are greased.
Oct 22, 2004
930
4
18
Arlington, MA
May 19, 2005
#19
  • May 19, 2005
  • #19
There are basically 3 reasons a car burns oil: worn rings, valve seals and PCV belching oil into the intake. The pcv can be tested by disconnecting it and see what happens to burn rate, the valve seals can be tested by replacing them or swapping heads (which he already wants to do anyways) changing the seals at the same time, and the rings you can do a leakdown but replacing them requires a rebuild anyways.

Introducing synthetic into a high milage motor will always result in burn unless this was a babied engine from day one. None of my 100K+ cars could hold synthetic at better than 1 quart per tank (the best one: my 87). That stuff is so thin, it goes right past the rings and seals.

Band aids work just fine. I band aided 3 cars like this and just drove em for years. I rebuilt one engine too just to say I did it.

Look at it this way: Gas costs $25 for a tank. If you burn 1/2 a quart of oil per 2-3 fillups , you can compare the $1.50 quart of oil to the $50-$75 of gas and decide that it's not economical to do a $1000-1500 rebuild to save yourself a few $1.50 quarts of oil. You wont even notice the expenditure next to fuel costs. Just have to remember to check the level.

Now a leak is a different story....bascially in that it's like a free sealcoating on your driveway and you generally park out on the street when you visit your friends instead of pulling in.

Plus switching to gt-40p's is not mutually exclusive with a rebuild. The 2 can happen independantly with a small replication of effort. Plus while the heads are off, you can remove al the carbon on the piston tops and maybe buy yourself an extra few 10,000 miles out of the motor.

Have fun!
 

5spd GT

"the 5.0 owns all"
Founding Member
Aug 7, 2002
9,516
6
99
Arkansas
May 19, 2005
#20
  • May 19, 2005
  • #20
Re-ringing/honing won't cost $1,000-$1,500

All those quarts add up...if money is tight...go for the band-aid...but eventually it will catch up with you and you will need a rebuild eventually anyways
 
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