97/98 Mark VIII another difference vs. gen 1

46callaway

46callaway

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I found out today the 97/98 Mark VIII engines come with the Cobra high output oil pump versus the standard 2V GT oil pump in the 93-96 Mark VIII...
 
What is false? The gen 2's have the H.O. Cobra oil pump, confirmed by 3 different people on Modular Depot who have seen it. The 96 Mark VIII might have it as well but this hasn't been confirmed.
 
I HAVE PUT 13MM billit gears in 93-96 Mark VIII oil pumps. I did this just a couple months ago. I don't care what the modular depot guys say. The GT's have 12mm oilpumps, mark VIII and cobra's have 13mm pumps.
 
Ponyfreak said:
This is false. I have put the 13mm billet oil pump gears in 93-95 mark VIII oil pumps.
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So....for us to understand better, you could have said "all M8s come with the high output cobra pump" or "I have installed the cobra pump in the gen1s because this is what they come with stock" instead of describing the size of the gears because we were all lost on that one. :D
 
Here is another poster from the Modular Depot who confirms the early Mark VIII's had the GT oil pump:
"I have 2 Mark VIII pickups here, GT (early) and HO (later). The early GT style tube has an OD of 0.825" and the later HO has an OD of 0.955" They both have the same crank scrapers, and they will only bolt up to the matching pump. The early GT is a duplicate of a stock Tbird/Cougar pickup with the scraper brazed on.

The early MarkVIII had 12mm pumps, I know because I have one."
 
J said:
So....for us to understand better, you could have said "all M8s come with the high output cobra pump" or "I have installed the cobra pump in the gen1s because this is what they come with stock" instead of describing the size of the gears because we were all lost on that one. :D
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Let me make it a little more clear for those who have never even seen a 4.6 oilpump in person. You cannot physically install 13mm wide gears in a 12mm case and have the proper clearance. So if 13mm billit gears fit in a stock mark VIII oilpump case it must be a 13mm oilpump. Also if you stick 12mm gears in a 13mm case you will have WAY more than the .002" tolerance required.

Now everyone listen to me for the last time. I HAVE STUCK BILLIT 13MM GEARS IN STOCK MARK VIII PUMPS. Plural "pumps" meaning 3 pumps now. These pumps ranged from stock 94-96 mark VIII's. These pumps are identical to the cobra's. All 4.6's came with the 13mm pumps due to the extra oiling capacity needed in the valvetrain.
 
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46callaway said:
Here is another poster from the Modular Depot who confirms the early Mark VIII's had the GT oil pump:
"I have 2 Mark VIII pickups here, GT (early) and HO (later). The early GT style tube has an OD of 0.825" and the later HO has an OD of 0.955" They both have the same crank scrapers, and they will only bolt up to the matching pump. The early GT is a duplicate of a stock Tbird/Cougar pickup with the scraper brazed on.

The early MarkVIII had 12mm pumps, I know because I have one."
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That post doesn't confirm jack crap.

He is correct that the oil pickup tubes are a lot different from mark VIII to Cobra. This is due to the tight fit of the mark VIII oilpan. The pickup tube is a smaller diameter, not mandred bent and shorter.

A cobra pickup tube will DIRECTLY bolt onto a stock mark VIII if you have a cobra pan. Again, I know this because I have had TWO cars that I have done this to. My brother currently runs a cobra pickup tube, cobra aluminum moroso pan with a stock mark VIII oilpump and billit oilpump gears.

I would bet this guy on modular depot is associating the pickup tube with a 12mm pump and making assumptions.

In summary: You can believe this jerk off internet mechanic or someone that actually knows WTF he is talking about because he has done it with his own two hands multiple times. I don't know of anyone that has owned, completely dissassembled and worked on more mark VIII's than myself. The only guy I know that has installed more engines than I have is the polish immigrant that works for Dennis Reinhart.
 
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Ponyfreak said:
You cannot physically install 13mm wide gears in a 12mm case and have the proper clearance. So if 13mm billit gears fit in a stock mark VIII oilpump case it must be a 13mm oilpump. Also if you stick 12mm gears in a 13mm case you will have WAY more than the .002" tolerance required.
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See, that makes more sense, but when you just refer to just installing billit gears into a 93-95 M8, most of us are clueless. You're like me and see things technically and "visually" in our minds, but for those of us that can't picture it....a simple statement like your first one was kinda "out there" :D

Ponyfreak said:
All 4.6's came with the 13mm pumps due to the extra oiling capacity needed in the valvetrain.
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Do you mean ALL 4.6 4cammer's or every 4.6L ever in all the cars(stang/crown vic/grand marqui etc.)?
 
I meant to say all 4.6 DOHC's. I have read in multiple genuine ford publications that all 4.6 DOHC's have the 13mm gears because of the need for increased oiling in the heads.
 
ALL Cobra pumps have 13 MM Pumps with .995 Pick up tube.
Early Mark VIII's have 13 MM Pumps .825 pick up tube.
Late Mark VIII's have 13 MM Pumps with .995 Pick up tube.
 
stpro is correct. when i switched to the melling cobra pump on the gen 1, the inlet tube diameter was incorrect and had to be modified or replaced.
 
Holly crap, when I just started to read this thread today I thought Joe had surfaced after all this time, then I read the date of his posts.
 
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