Mark VIII performance, Whats next?

k9t8m

k9t8m

Rollin' Twankies
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Last night I went to the track (see other post) and tried to get into the 14's and ran 15.034. I would like to do some mod to get my car to consistantly run 14's.

Here is a list of things I have done to the car thusfar:
K&N drop in filter
removed all air silencers
MSD wires
Autolite 764's
Magnaflow catback exhaust
245\45\18 tires
Switched all fluids to synthetic
SCT xcal2 from Torrie

For now i just want a little more power. I plan on supercharging in the future, so anything that i can later use for that buildup would be great.

I thought about gears, but I drive 110 miles to the track on the highway, and thats pretty much out of the question. Not to mention the cost.

UD pulleys would also be an option, but I dont know if that will be enough to notice a difference.

What other options do I have that dont cost a fortune?

high flow Fuel pump?
Elec water pump?
Now might also be a good time to throw on a cobra intake setup.

I would like to do sonething that doesnt take to long to put on though, because i plan on going back to the track a couple more time before the season is over.

Let me know, I'm very excited to order some parts and go racing again soon!
 
Go back to stock wheel's and tires. The lower rotating weight will get you into the 14's if everything else is created equal.
 
If you are looking at a Cobra manifold then you are probably looking to go with a Centrifical Super Charger. That being the case then I suggest you poney up and get a 4:10 set of gears with Eaton Posi, new drive shaft, and chip update. Guys driving with 4:10's all over the place. It's no biggie, and then you will adleast have that part of your total mod done.
If you are considering Twin Screw or Eaton SC then 3:73 gears are ample.
 
NOS? Check the link in my sig if your intrested.
 
k9t8m said:
I thought about gears, but I drive 110 miles to the track on the highway, and thats pretty much out of the question. Not to mention the cost.
Click to expand...

I have 4.30s and drive on the highway to the tracks all the time.

Gears and a high stall converter will give you a new car.

A quickie? Baumann shift kit. ;)
 
I drive to work every day 90 miles round trip with 3.73s. I get 22 mpg. Reconsider gears.
 
Thats so strange Brent because i have 4.10's and average 18.2 and get highway of 26 at 75 mph. Many people report better MPG and longer between fill ups with geared Marks.
 
ONEBADMK8 said:
Thats so strange Brent because i have 4.10's and average 18.2 and get highway of 26 at 75 mph. Many people report better MPG and longer between fill ups with geared Marks.
Click to expand...

That just does not make sense to me. The engine is working harder how is it going to get better MPG
 
no, actually it isn't working harder. Engines produce their HP higher in the RPM band. Torque usually tops out between 2500-3500. Bringing the cruising speed of the engine into a more efficient RPM is basically what you've got happening. There is a point where everything evens out, you make the most numbers for the least fuel. Below that and the engine is actually working too hard to push you along; this consumes additional fuel. Above that small zone and your producing far more power than you need; this too is at the expense of your fuel bill. Depends on the vehicle, how it's used and how it's driven.
 
A geared car may help in the mpg department around town where the gear helps get the car 'up to speed' faster but I would have to be 'willing to suspend disbelief' (Hilliarism) in order to believe that shorter (numerically higher) gears will help your highway mpg.

Don't take my word for it, do your own test.

Drive around on the freeway in 4th gear and measure your fuel economy, then take off the overdrive and drive around for the same amount of time or distance.

The difference between 3rd and 4th gear is the nearly the same as a Mark running stock gears vs 4.10's, etc. so I think the comparison of the rpm differences make the comparison valid, much less to say that driving in 3rd, which is a direct gear drive on our cars, means you are not turning an extra gear as you would in overdrive.

If you want the maximum fuel economy, run 3.07 gears, or better yet, you can get a set of 2.73's out of a Crown Vic and try those.

If you live in an area of hills and valleys, then yes, the lower (numerically) gear sets, 3.27, 3.07, 2.73 will lag the motor more and will require more gas pedal travel (fuel) to maintain the same mph on slight uphill stretches. Where you pick it back up is when on flat or slight downhills where you can take your foot off the throttle occasionally and left the motor run off vacuum for short bits. You can prove this also by running your car, say set at 70 mph with the cruise control ON, and then rerun the same stretch manually adjusting the throttle to maintain 70 by taking advantage of the downward slope to ease off the gas completely for short periods as you 'coast'.

Having driven more than a couple hundred thousand miles in these cars has allowed me the ability to provide you with this unique and in-depth analysis.:lol:

And lets not forget that the faster one drives, the more air resistance the vehicle encounters, which will also have a detrimental affect on mpg.
 
MonsterMark said:
The difference between 3rd and 4th gear is the nearly the same as a Mark running stock gears vs 4.10's, etc..
Click to expand...

This is absolutely correct, we compared my friends 410 car to my 307 car {before i did the gear swap) and that is exactly what we discovered.

410 car IN overdrive same RPM's as a 307 car in third gear when driven at the same speed "side by side".

That is what I tell anyone who asks.. "are 410's too much"?
I always say.. take a ride with your OD turned off...and you tell ME if 410's are too much
HAHA


MonsterMark said:
Having driven more than a couple hundred thousand miles in these cars has allowed me the ability to provide you with this unique and in-depth analysis.:lol:
.
Click to expand...

Same here, at 396,000 miles I think I've pretty much ran into EVERYTHING under the sun, except the moon.
 
just for reference, I was not implying that 4.10, 4.30's or 5.10's would give better mileage. But to argue that if a 1:1 ratio were available, you'd get the best mileage with this gearing, it would be extrodinarily inaccurate. I have personally seen mileage improvements in mustangs going from 2.73's to 3.55's. As stated before, the engine needs to be operating in a RPM range where it will be most efficient with concern to the vehicle. This is not idle... and it is not 3500 RPMs.

This is somewhat like arguing the point that more HP will automatically mean less MPG. There is a "sweet spot" of efficiency for both the power output of an engine and an RPM used to move a car. And I think we all know the OEM usually misses the mark on that sweet spot for power(were this not the case, CAI, Cat-backs and tuners would never show a mileage gain). So is it hard to imagine they perhaps don't have it just right for the gearing?

But as said, where you drive, how you drive... and what you drive play a roll in mileage and the best gearing option.
 
NateRW21 said:
But as said, where you drive, how you drive... and what you drive play a roll in mileage and the best gearing option.
Click to expand...

"where" you drive and "how" you drive will have the largest impact on mileage.

As you said in regards to the "more HP=Better ecomony" the same applies to gear swaps as well.

Just because someone changes to 410's doesn't really mean they are automatically going to get worse gas mileage.

Of course if they run around "enjoying" their new found performance then absolutely they are going to get worse gas mileage.

Example, I'm sure I could drive a 410 car "with care" and get far better gas mileage that someone "hot rodding around" with 307's.. and VICE versa.

If I hotrodded around with 410's and drove the 307's "with care" I'm sure I could make a HUGE difference in MPG... it's all really a matter of "HOW and WHERE" you drive..as Nate said.
 
Don't think I'm trying to argue... I mostly agree with you (as I think you can see); I'm just making a blanket point that there is no one solution to fit everyone.

All this talk of mileage did make me think... I one time got 29 (I believe it was 29) mpg in my LS doing about 65mph... do you think I've been able to replicate that since? HELL no... talk about agrivating... best I've been able to do since then was about 25ish. If only I had a constant tail wind that followed me everywhere I go.
 
Geno - I get close, maybe a little lower than you. (Gen2 vs Gen1?) On the highway I'm getting 24-25 and around town I'm getting 18 so I'm avging 22. I was telling him to reconsider the gears because I think 22 avg city/hway is pretty damn good for a car than runs 14.1. Sorry if the first post was unclear. He was saying he wasn't going to consider gears, I was trying to tell him to reconsider.

Short version: GET GEARS
 
MPG? :D

You're driving a Luxury Sport Coupe. If you want mpg, maybe you should be driving a prius. :p
 
quick question, around town, does driving with o/d off make a difference?

what about driving on the highway with o/d off?
 
NateRW21 said:
Don't think I'm trying to argue... I mostly agree with you (as I think you can see); I'm just making a blanket point that there is no one solution to fit everyone.

All this talk of mileage did make me think... I one time got 29 (I believe it was 29) mpg in my LS doing about 65mph... do you think I've been able to replicate that since? HELL no... talk about agrivating... best I've been able to do since then was about 25ish. If only I had a constant tail wind that followed me everywhere I go.
Click to expand...

Good discussions often seem like arguments and they aren't..no worries.
I'm not argueing either, you made some good points.

Often we'll drive from Houston to up by Austin.
The difference between going "to" austin and driving "from" austin is almost 5 MPG.
I can get 23-25 on the way up there {up hill the entire way} and 27-29 on the return trip... using cruise control the whole trip.
I know I could get better mileage if I didn't run on cruise control.

If your shooting for good gas mileage, you might try what I do.
I overinflate my front tires by 10LBS, it does affect ride quality..to some extent making expansion joints a little harsher, but does help in the economy dept.
I run 45 in the fronts and 35/36 in the rears on road trips.

Give it a shot...
 
The Rev said:
quick question, around town, does driving with o/d off make a difference?

what about driving on the highway with o/d off?
Click to expand...

There is a CHANCE that if driven with great care and consistancy you COULD net better gas mileage around town if you drove with OD off.
BUT.. one laspe in consistancy would erase any gains you might have gotten.

On the hiway, unless you have a GOOD aftermarket tranny cooler I wouldnt' drive for extended periods with the OD off.

The stock tune in third gear has alot of what is called "steady state slip" programmed into the PCM for the Torque Convertor, unless you have removed that in the tune, your gonna make ALOT of tranny head driving extended periods with OD off.

The stock tune also allows "steady state slip" in second gear as well, just for conversations sake.
 
This is a completely accurate statement...............

NateRW21 said:
just for reference, I was not implying that 4.10, 4.30's or 5.10's would give better mileage. But to argue that if a 1:1 ratio were available, you'd get the best mileage with this gearing, it would be extrodinarily inaccurate. I have personally seen mileage improvements in mustangs going from 2.73's to 3.55's. As stated before, the engine needs to be operating in a RPM range where it will be most efficient with concern to the vehicle. This is not idle... and it is not 3500 RPMs.

This is somewhat like arguing the point that more HP will automatically mean less MPG. There is a "sweet spot" of efficiency for both the power output of an engine and an RPM used to move a car. And I think we all know the OEM usually misses the mark on that sweet spot for power(were this not the case, CAI, Cat-backs and tuners would never show a mileage gain). So is it hard to imagine they perhaps don't have it just right for the gearing?

But as said, where you drive, how you drive... and what you drive play a roll in mileage and the best gearing option.
Click to expand...

Every engine has it's sweet spot where it produces maximum HP with minimum fuel consumption. Torque gets a car moving and then HP keeps it at that speed. There have been many dyno tests done that prove this point. Engines have been run on the dyno at various RPM levels and fuel consumption measured under load. It is not always, as a matter of fact almost never was it the engine that had the lowest fuel consumption, that was running the lowest RPM's. I can get as much as 32 MPG highway in my Mark VIII with cruise off at a steady 60 MPH on the highway. But I have been able to achieve 35 - 36 MPG's on the exact same road, going in the exact same direction doing 65 MPH. Only difference was that I was driving faster and therefore at a higher RPM. And I did this more than once last year going to the beach. At first I did not believe the difference. So I did it again and repeated the results. Did the same thing in my Dodge Ram, only in that I did the same speed, just one time I made the drive in fourth and the other time in overdrive 5th. Lots of guys on the Ram forum have reported similar better MPG results by switching to 456 gears. Just like airplanes, we use more fuel getting our cars up to speed than we do to maintain speed. Want to prove that to yourself, Zero out you MPG's on your computer and watch the instant MPG readings getting to speed VS at speed.
 
I absolutey agree..

Driving 60 I can get 30+ with 373's, no problem.

The mileage doesnt start to fall off until I get to 65-70ish
{which is right above 2K on the tach)

Some say putting gears in the car kills the mileage but actually they help mileage if driven in a proper and consistant manner.

Before the gear swap, my car was running at 12-1400RPM's which is "too low" .
moving 500 rpms up the scale really did improve driveability and I wind up using "less gas pedal" to get the car moving.

Gears really are a plus IMHO
 
bufordtpisser said:
I can get as much as 32 MPG highway in my Mark VIII with cruise off at a steady 60 MPH on the highway. But I have been able to achieve 35 - 36 MPG's on the exact same road, going in the exact same direction doing 65 MPH. .... Want to prove that to yourself, Zero out you MPG's on your computer and watch the instant MPG readings getting to speed VS at speed.
Click to expand...

:bsflag:

I miss smoking pot.:slam

Fill up your tank, drive a long distance, fill up the tank to the same level. Take miles driven divided by gallons added and presto, mpg. Everything else is bunk and a 3.73 equipped Mark getting 35-36 mpg is total bunk.

Just fighting fiction with reality.:drunk:

I wonder sometimes how much money Ford wasted trying to obtain 18 city and 26 highway ratings for this car when they just could have went to one of you guys for the expertise of adding some 3.73's or 4.10's or heck, 4.56's must get 40 mpg, using some fancy new one-step colder plugs, taking the spare out of the trunk, and putting that fancy Mobil 1 in the crankcase and increasing the mpg by 35%.

Ford doesn't even need the new Eco-Boost motor now. All they have to do is add an electric supercharger instead of the direct-port twin-turbo that runs on E-85 they are introducing now.
 
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