Duals For My '85 Mark VII

mespock

mespock

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I am going to have Duals made for my '85 Mark VII

I think I going to have the guy delete the Cats (I can do this where I live)

Then bend what I need!

Anything I should know before I start this project! Tips for a little extra Hp or something! Good advice for old (young) Pros!

I am also looking for good mufflers! I want something with a nice sound but not overbearing.

I know Dave has Raven on his VII and I liked the sound!
 
Do you have single xhaust on your 85'. I know on my 84' I got single. So, I went like this. Off the manifolds 2.25" into Y-pipe, into Hi flow cat. Out 2.25 into flowmaster 40S Dual out 2.00".
 
Sifrino3 said:
Do you have single xhaust on your 85'. I know on my 84' I got single. So, I went like this. Off the manifolds 2.25" into Y-pipe, into Hi flow cat. Out 2.25 into flowmaster 40S Dual out 2.00".
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I have a single exhaust! I can delete the cat! I do belive correct me if I'm wrong the it's better without the Cats!

Do I have to go to a "Y" can I keep it Dual all the way if possible?
 
mespock said:
I have a single exhaust! I can delete the cat! I do belive correct me if I'm wrong the it's better without the Cats!

Do I have to go to a "Y" can I keep it Dual all the way if possible?
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I have no cats on Sifrino. Don't know if it is better. But it hurts the air. You don't have to go with a y-pipe. But you are not making much power with your 85'. Just like my 84'. It will be cheaper to do it like Ovr Cst. I figure a few $100 cheaper. Ovr Cst: One muffler, y-pipe, and tips. Sifrino: Two mufflers, x-pipe (Easly double over y), and tips.

You don't need any pipe over 2.25". Some one muffler dual outlets actully flow better then some dual mufflers. In some cases. I think I heard that in a Camaro section. I dunno, its up to you in the end. No one can really see under your car. If you wanted it for looks. Its really about sound "Flowmaster" with some HOT looking tips.
 
If you're doing duals like the later model Marks, make sure there's a crossover pipe between the two. You know, the "H" in h-pipe.

Good luck and have fun!
 
Honestly it really won't be worth your time and money to waste on a true-dual setup. From the picture in your signature you have a 1985 BB, which came equipped with a 140hp non-H.O. engine. The stock exhaust is more than efficient for the motor. A true-dual configuration will give you a large hole in your pocket and a broken heart, as you will most likely feel a loss of power via your butt-dyno. The low-end performance will suffer. And please don't delete your catalytic; again, there will be no major increase in power (unless your current one is in disrepair) but there will be a major increase in pollution. There are guys out there running quite fast with catalytics, and there are many aftermarket high-flow units that it's worth it to save the planet and your car from passing emissions.
 
Few Questions! I know in a past post that the 85' basically has no way if really increasing Hp! Like now way to get it over 200 hp! At least that's what I have gotten from those who have replied! Bummer!!

This is a very nice and clean car, and I like it! But I'd like to get a little more performance out of it! I don't want to add an exhaust just to get sound or looks! I am hoping to improve it's breathing!

What I'm looking for basically is to get a little more go, not much I'm not looking to race this thing, but a little more go when I step it down to pass! The car has power and she does like speed but I'd just like a little more snap to it. I was hoping that air flow would help!

I like the Mark VIIs I love their class and style. Would I be better to just sell this unit and look for a newer modle with the HO 5.0 and invest what cash I scrounge up for an newer modle!
 
You want it faster? Drop in a carburated 5.0HO or a 351W. Or just find a 1988+. Don't dick around with that engine, it's not worth it. Not in the least. non-roller cam = different firing order. Your computer isn't made for real fuel injection, and swapping engine harnesses is not anyone's idea of fun. Save your money.
 
CaptainZilog said:
You want it faster? Drop in a carburated 5.0HO or a 351W. Or just find a 1988+. Don't dick around with that engine, it's not worth it. Not in the least. non-roller cam = different firing order. Your computer isn't made for real fuel injection, and swapping engine harnesses is not anyone's idea of fun. Save your money.
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I think he wants to use what he has. Not go out and buy a whole new car or engine. Xhaust doesn't really give you much anyways. Gears or TC would make you happier. . .
 
JoshMcMadMac said:
Honestly it really won't be worth your time and money to waste on a true-dual setup. From the picture in your signature you have a 1985 BB, which came equipped with a 140hp non-H.O. engine. The stock exhaust is more than efficient for the motor. A true-dual configuration will give you a large hole in your pocket and a broken heart, as you will most likely feel a loss of power via your butt-dyno. The low-end performance will suffer. And please don't delete your catalytic; again, there will be no major increase in power (unless your current one is in disrepair) but there will be a major increase in pollution. There are guys out there running quite fast with catalytics, and there are many aftermarket high-flow units that it's worth it to save the planet and your car from passing emissions.
Click to expand...

Dude mentioned sound and looks and for sound and looks, a dual set up on his single exhaust system would be a cosmetic upgrade. One or two Flowmasters series 40s would make it SOUND good without setting off car alarms.
 
From Sif - I think he wants to use what he has. Not go out and buy a whole new car or engine. Xhaust doesn't really give you much anyways. Gears or TC would make you happier. . .

I'm not sure what I want in the way of the car. I like the car I have but would like it to have a little more kick not much just a little! I was told that improving how a car breathes with help add a boost! Remember I'm an old Rookie here! So I know only enough to get myself in trouble LOL. So depending on the cost! Seeing I owe my Mark VII out right, it might be better to just wait until that right 88 or better Mark VII come along. I do have my daughter's 88 Thunderbird SC with the HO 5.0 in it. She's told me the car is mine when she's done with it. She only has $250 wrapped up in it and the engine is fantastic. I could use that engine for the swap or play with the Thunderchicken and leave my Mark VII as is.

From Old School - Dude mentioned sound and looks and for sound and looks, a dual set up on his single exhaust system would be a cosmetic upgrade. One or two Flowmasters series 40s would make it SOUND good without setting off car alarms.

I really don't want to add anything that will improve sound unless it give me Hp! I don't want to be a ricer sound good with no go! So, on this issue I'm not sure what I want to do! I could replace the single muffler with one that has dual exit ports then run the second pipe for looks that's all I'd get is looks so I'm not sure. I did listen to Dave's Raven mufflers and I did like the sound that they gave, but now I am not sure what I want to do!

If 140 Hp is all I'm going to get and no hope of getting it up to 200 then I might as well keep this beauty looking sharp and invest in only cosmetic such as rims and keeping the body and interior looking good maintain the engine so it stays running nice.

Capt Thanks for you input! After our last meet trust your opinion!

Pro-five-oh I think you explained this earlier in the summer I was just hoping. You really know your Mark VII that's why I look for your imput on LOL. as with you JoshMcMadMac and NYC LSC Love your VII's

Sif at 18 you've done more than I'll ever with a car!

And OS Have no fear if someone will have an idea I know you'll have one!

Thanks all! Now I'll see what I do this spring!
 
Mes - Xhaust will help. But like on any car. Its never a for sure bet. Some engines will produce more power then others with the same xhaust. What some people are saying. Is that engine really instn't resticted. But do the xhaust. You will feel a little bit more mid range power. It just might be what you want. I could hook you up with the main peices for $100 or so. Then it would be up to you. To find a shop that will give you a good deal.

Im telling you though. True duals are not the way to go. You should do a set up like Ovr Cst will have. Well, has. But is not installed yet. That should give you a little more boost. Also, if I am thinking right. Getting a throttle body form an 88-92 MVII. Will give you better flow. Im guessing that your TB is less then 62mm. AZLSC is selling his TB/EGR cheap. I was thinking of getting it for Venecia. An 1986 MVII LSC. So, measure that!

Ram Air Time. Buy a kit for an 89-93 Mustang Ram air kit. This will keep a good pressure in you intake. Just incase and now that im thinking of it. Thats the way to go Mes!

Ram Air Kit (89-93 Mustang GT) $100+
62 mm TB/EGR (88-92 MVII) AZLSC $50 Give Offer
2.25" Y-pipe (Ebay Search Y-pipe) $10 Maybe a Few More
2.25" Cat (Search Catilyc Converter) <~~~Spelling $40 or Less
2.25" I Dual 2" O 40S Delta (Ebay Search Flowmaster) $40 or Less

I will tell you right now. You will be happy. Because at highway speed and you want to lay it down. Your MVII will go. If it doesn't I will buy back the TB/EGR and Ram Air Kit from you. So, there you go. What are you waiting for!
 
Do not change your headers or xhaust manifolds. Which ever one you have. You will lose some low down torque off the line. Other then that. I would get a nice set of Spark Plug Wires and of course Spark Plugs. If needed cap and rotor also!
 
This is Sifrino!

This is Sifrino. 1985 is still carbed isn't it. I though you had a 1986. My bad, the xhaust still works. Will have to figure something out with the intake. You do have the cool 5.0L on your intake don't you. That is cool I want an 85' intake. But anyways, makin a ram air isn't all that hard. I was scoping out Ovr Cst and it is due able. But just thinking of whats the best size tubing and what not to use. You know what im saying. Don't the 85' have the dual intake. So, you could run a dual ram air!
 
Ovr_Cst said:
This is Sifrino. 1985 is still carbed isn't it. I though you had a 1986. My bad, the xhaust still works. Will have to figure something out with the intake. You do have the cool 5.0L on your intake don't you. That is cool I want an 85' intake. But anyways, makin a ram air isn't all that hard. I was scoping out Ovr Cst and it is due able. But just thinking of whats the best size tubing and what not to use. You know what im saying. Don't the 85' have the dual intake. So, you could run a dual ram air!
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Remember I'm and old rookie so I'm not sure about a lot I'm learning as I go!

I will let the experts who may read this thread relpy as to carb or FI.

FYI - In our local Bone Yard is nother 1985 Mark VII engine intact. So if you need anything from it! let me know!

Sif (3) Your above post is exactly what I'm looking for! Something so when I go to pass I have just a little more punch! If that's what your are explaining! Not looking for a racer I'm looking for something that just says Hey there's more than 4 Cylinders under this hood. Then I don't mind having a little more rumble to my exhaust!
 
You're welcome.

Basic tune up with all new parts.

New Battery and starter for perfect starts.

New altenator and regulator at the same time.

You'll be able to pass with confidence.
 
mespock said:
I do have my daughter's 88 Thunderbird SC with the HO 5.0 in it. She's told me the car is mine when she's done with it.

If 140 Hp is all I'm going to get and no hope of getting it up to 200 then I might as well keep this beauty looking sharp and invest in only cosmetic such as rims and keeping the body and interior looking good maintain the engine so it stays running nice.
Click to expand...

HO 5.0? Someone did the HO conversion on it? That's very cool.

And I think you are spot-on with your plans for the 1985 Mark. Just keep it lookin good. You have a Mark VIII for performance when you need it. :)
 
Mespock, you need to take a few steps back from Sifrino's rambling. He has made a lot of suggestions, and I don't think any of them are a good idea, and many of them will not work. Your car does NOT run off of a carb like he stated; you have a form of Fuel Injection, CFI. Also, the throttle body idea won't work and certainly wouldn't improve power at any point.

Now, one last time, back to the exhaust. An aftermarket exhaust will most likely not improve power at any point in the PRM band, and more likely will cause a loss of power throughout the powerband. While the theory that "back pressure is the enemy of power" is correct, you must also remember that the stock exhaust is fine tuned for your application. Certain lengths of pipes, the length and location of the cats and muffler are all designed to optimize overall performance. Having a different setup installed is a grab bag. You might get lucky with a setup that gives a FEW horsepower, but you'd have to get pretty lucky.

I suggest that you keep it tuned up and looking good, then find a more suitable starting point for your high-performance fun...like your VIII. ;)
 
JoshMcMadMac said:
Now, one last time, back to the exhaust. An aftermarket exhaust will most likely not improve power at any point in the PRM band, and more likely will cause a loss of power throughout the powerband. While the theory that "back pressure is the enemy of power" is correct, you must also remember that the stock exhaust is fine tuned for your application. Certain lengths of pipes, the length and location of the cats and muffler are all designed to optimize overall performance. Having a different setup installed is a grab bag. You might get lucky with a setup that gives a FEW horsepower, but you'd have to get pretty lucky.
Click to expand...
I'm not sure and I doubt that I have the OEM muffler! The tail pipe looks like a bend job done after the current muffler was installed.

What do you suggest then with this..as the current muffler looks like it hangs low! It's tight just looks like it does not belong! I'll try an post a pick tonight after I get home from work.

From pro-five-oh
pro-five-oh said:
HO 5.0? Someone did the HO conversion on it? That's very cool.
Click to expand...
What do you mean!!


Back to Josh
JoshMcMadMac said:
I suggest that you keep it tuned up and looking good, then find a more suitable starting point for your high-performance fun...like your VIII. ;)
Click to expand...

Have to wait until my wife is done with my Mark VIII but this shouldn't take too long. Claims it at hers! No comments Bryan :p
 
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