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

[jaymac]

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]

My short block was in good shjape at 190,000 miles and I put the same stuff on mine.

 

[89rdgt]

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]

Did the same thing........ran it another 50k after that. Now he same stuff is on my 347.

 

[RYC CUKR]

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]

sounds like "all systems go " to me

 

[mackey]

~120k miles. Trickflow H/C/I runs low 13s.

 

[Aliate X]

What if your engine is burning oil? Say 2 quarts every 2 or 3 weeks?

 

[Curse]

Only problem I see you having is, no traction Good luck

 

[5spd GT]

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]

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

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]

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]

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.

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]

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]

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]

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]

Im running 10w-30 right now, ill switch over to the 20-50 and see what happens....

 

[5spd GT]

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]

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]

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