What's wrong with the Mark VIII engine?

[Motorhead350]

Thank you!!!

You shed light on a very important subject and that is the exhaust ports. I don't want to buy new headers or modify mine, at least not right now.

Aviators are showing up in yards so that's what I'll pull from for heads.

Thanks again!

[Chayton]

On the contrary I have heard some people say great things about the B heads (maybe when theyre ported out?)

Im actually dropping a Mark VIII engine into my 2002 crown vic sport at the moment.

[Chayton]

Thank you!!!

You shed light on a very important subject and that is the exhaust ports. I don't want to buy new headers or modify mine, at least not right now.

Aviators are showing up in yards so that's what I'll pull from for heads.

Thanks again!

I heard headers for c port heads will work with b heads but not the other way around. Or something like that. ??? Im having trouble finding cheap headers for my B head motor.

[massacre]

On the contrary I have heard some people say great things about the B heads (maybe when theyre ported out?)

Im actually dropping a Mark VIII engine into my 2002 crown vic sport at the moment.

Sorry to hear that.
Unless you are John Mihovetz running 30# of boost in a track-only car, B heads are garbage.
Intake ports are way too big for street car, this is well documented all over the place. Porting them will just make that situation worse.
If twin intake ports were that great, Ford would still be making them. It was Ford's original design, trying to induce "swirl" into the combustion chamber. That is late '80s/early '90s technology, the "tumble port" C heads outperform the B heads substantially and consistently.

Dom you can use your C head headers but the B head exhaust ports are way smaller, you won't be able to reap the benefits of the huge C head exhaust port.
On a side note, I can't believe we are still talking about B head/C heads in 2017.

[Chayton]

Sorry to hear that.
Unless you are John Mihovetz running 30# of boost in a track-only car, B heads are garbage.
Intake ports are way too big for street car, this is well documented all over the place. Porting them will just make that situation worse.
If twin intake ports were that great, Ford would still be making them. It was Ford's original design, trying to induce "swirl" into the combustion chamber. That is late '80s/early '90s technology, the "tumble port" C heads outperform the B heads substantially and consistently.

Dom you can use your C head headers but the B head exhaust ports are way smaller, you won't be able to reap the benefits of the huge C head exhaust port.
On a side note, I can't believe we are still talking about B head/C heads in 2017.

Sorry to hear what?

and no youre right, I just had trouble remembering why they said they were good. It was for boost, not being ported out. 30# sounds a little extreme.

[massacre]

Sorry to hear what?

and no youre right, I just had trouble remembering why they said they were good. It was for boost, not being ported out. 30# sounds a little extreme.

Didn't mean to offend with the sorry statement, it's just that to go through all that trouble of the swap and keeping the B heads, you are leaving a lot of performance on the table, and limiting yourself quite a bit on performance parts options.
Yes 30# is extreme but that's why I said you would have to be John Mihovets to say that B heads perform well. Not sure if you guys know who he is, but he has made more power and gone faster than pretty much everyone and has been doing it for decades. Here's a motor he built for an Engine Masters build off

http://st.hotrod.com/uploads/sites/2...am-detail1.jpg

^^^ gotta love that airbox lol
I tried to post the pic but I think it's too big.
Looks like even Mihovetz is using C heads now.

If you're a Modular freak like me, you'll enjoy this article from the same year Engine Masters. It's a John Kaase Modular build (also with C heads) with some of the craziest headers I have ever seen in my life. He explains the reasoning for the design, and it's relationship regarding exhaust pulses and torque production in Modular engines. Motor made over 700hp over 600lb/ft and this is NA.

http://www.stangtv.com/news/jon-kaas...asters-winner/

It's the whole "swirl port VS tumble port" thing, the tumble port heads are so much better breathing heads than the swirl port.
The B head Cobra cams though have more duration, they make good power in the tumble port heads, more than the tumble port cams when degreed properly.

[massacre]

BTW
B heads on a 5.4 block work much better than on a 4.6

[Chayton]

Didn't mean to offend with the sorry statement, it's just that to go through all that trouble of the swap and keeping the B heads, you are leaving a lot of performance on the table, and limiting yourself quite a bit on performance parts options.
Yes 30# is extreme but that's why I said you would have to be John Mihovets to say that B heads perform well. Not sure if you guys know who he is, but he has made more power and gone faster than pretty much everyone and has been doing it for decades. Here's a motor he built for an Engine Masters build off

http://st.hotrod.com/uploads/sites/2...am-detail1.jpg

^^^ gotta love that airbox lol
I tried to post the pic but I think it's too big.
Looks like even Mihovetz is using C heads now.

If you're a Modular freak like me, you'll enjoy this article from the same year Engine Masters. It's a John Kaase Modular build (also with C heads) with some of the craziest headers I have ever seen in my life. He explains the reasoning for the design, and it's relationship regarding exhaust pulses and torque production in Modular engines. Motor made over 700hp over 600lb/ft and this is NA.

http://www.stangtv.com/news/jon-kaas...asters-winner/

It's the whole "swirl port VS tumble port" thing, the tumble port heads are so much better breathing heads than the swirl port.
The B head Cobra cams though have more duration, they make good power in the tumble port heads, more than the tumble port cams when degreed properly.

well when you put it that way, maybe. Keep in mind I said this is going into a 2002 vic, so right off the bat im picking up an additional 45 horsepower or so... for a complete motor I got for $200. Seems like a win to me. Id much rather leave it as is, change the valve covers and plop it in rather than do more work retiming the motor to gain what, 20 hp? More than happy with what Ive got. The car is going to be a drift anyways, lol.

[massacre]

well when you put it that way, maybe. Keep in mind I said this is going into a 2002 vic, so right off the bat im picking up an additional 45 horsepower or so... for a complete motor I got for $200. Seems like a win to me. Id much rather leave it as is, change the valve covers and plop it in rather than do more work retiming the motor to gain what, 20 hp? More than happy with what Ive got. The car is going to be a drift anyways, lol.

I get what you are saying. No reason not to be happy about gaining ~45 hp but you will be losing torque compared to the 2v and in a whale torque helps a whole lot, especially if you are going to drift with it.
But hey maybe it will satisfy all of your needs and wants, and if it does, good for you! But if you look into mods and go-fast parts, and I'm assuming you will want to mod it down the road since you are already doing a swap, you'll find there is just not a lot out there compared to the later stuff. I mean it can be done, but it's just so much more complicated generally speaking.
As long as you know this going in and don't have unrealistically high hopes you should be fine.
Not sure what year Mark engine you have but the '95s are notorious for having weak valve springs, they tend to break. Some '96 and 'all 97-'98 motors have same valve springs as Cobra and can rev to 7000rpm without issue.
Your powerband is going to move up considerably, I would recommend a higher than stock stall converter if you want to rev it up for drifting, this will help with torque as well.
Just my .02

[J-MAN]

I typed out a bunch of stuff but then deleted it
Prob better this way

+1

[Chayton]

I get what you are saying. No reason not to be happy about gaining ~45 hp but you will be losing torque compared to the 2v and in a whale torque helps a whole lot, especially if you are going to drift with it.
But hey maybe it will satisfy all of your needs and wants, and if it does, good for you! But if you look into mods and go-fast parts, and I'm assuming you will want to mod it down the road since you are already doing a swap, you'll find there is just not a lot out there compared to the later stuff. I mean it can be done, but it's just so much more complicated generally speaking.
As long as you know this going in and don't have unrealistically high hopes you should be fine.
Not sure what year Mark engine you have but the '95s are notorious for having weak valve springs, they tend to break. Some '96 and 'all 97-'98 motors have same valve springs as Cobra and can rev to 7000rpm without issue.
Your powerband is going to move up considerably, I would recommend a higher than stock stall converter if you want to rev it up for drifting, this will help with torque as well.
Just my .02

huh. So ill be making less torque with the 4v? I could have sworn I would be gaining horsepower AND torque.

I have a big stall in my marauder actually and not sure if I would want it in a drift application. Makes for less precise throttle control, IMO. At the most I will probably change the gears, if needed. We shall see.

You wouldnt happen to know anything about reversing the polarity on the COPS? Ive read it is necessary when doing a 4v swap. Thats the one part that concerns me.

[massacre]

Did you research this swap beforehand?
Yes the polarity needs to be swapped. It's not hard.
Tons have done it, info everywhere

[Chayton]

Did you research this swap beforehand?
Yes the polarity needs to be swapped. It's not hard.
Tons have done it, info everywhere

I did!


So how much torque will I be making approximately then!?

Thanks for the advice.

[massacre]

I'm not Nostradamus
Many factors can influence torque production
Not sure if trolling
2v generally makes more torque lower in powerband than 4v
Where are you searching that this info is not available?
I think I'm out it's been fun

[Chayton]

I'm not Nostradamus
Many factors can influence torque production
Not sure if trolling
2v generally makes more torque lower in powerband than 4v
Where are you searching that this info is not available?
I think I'm out it's been fun

I get what you are saying. No reason not to be happy about gaining ~45 hp but you will be losing torque compared to the 2v and in a whale torque helps a whole lot, especially if you are going to drift with it

Anyways end of topic. Thanks for sharing your wisdom, i will consider going back to 2v so i can get all meh torques back