9.2 MPG please help!!!!!

[black97mounty]

Just wait until you see the size of the #3 port---

Did you find a leak??

I dont have time to get the car up in the air until monday. No garage at my house and its like 10 degrees outside here in chicago. It can wait til monday to check it out

anyways, Im cutting the rear cats off monday and adding a nice high flow muffler. Should I just cut the cats off, do a y pipe (what size) and then a single in/out muffler?

I had a plan on doing a 2.25/2.5"" y pipe in/2.5 or 3" out. A 2.5/3" in muffler with a 2.5/3" outlet. I heard that 3" increaes tourque?

What's the best combo/easiest route?

 

[black97mounty]

1.0v on the TPS is the point where the PCM starts enrichment during acceleration. I agree with Jon, you are probably just fine at .89v and won't see this affect milage much if at all. I just always try to optimize everything out. In any event, don't exceed 1.0v. At.96 to 1.0v it would be very hard to perceive or even measure a difference.

Those factory "manifolds" are a nightmare. You can barely get a finger into a couple of the ports. The FMS headers are a head-and-shoulders improvement, and the Torquemonsters are a major improvement on those.

I wonder if the cats are getting plugged and causing restriction?

where can I get these FMS headers?

 

[bs46488]

Any update?

I have a 1997 with the same problem. On a good week I can get 10MPG, I think that is horrible. I'm not expecting 30 MPG, but a little more than 10 I think is reasonable.

I will also admit, I have a passenger side exhaust leak. I can hear it "ticking" when I accelerate. Can that cause that big of a problem?

FYI...All maintenance is up to day, and I only have 51k on the truck.

 

[black97mounty]

Any update?

I have a 1997 with the same problem. On a good week I can get 10MPG, I think that is horrible. I'm not expecting 30 MPG, but a little more than 10 I think is reasonable.

I will also admit, I have a passenger side exhaust leak. I can hear it "ticking" when I accelerate. Can that cause that big of a problem?

FYI...All maintenance is up to day, and I only have 51k on the truck.

I have a light tick from both sides aswell. Looks like a good excuse for a set of headers.

I think I may have just gotten some bad gas. I filled up the other day and got 12mpg. Not great, but better. I'm going to buy a set of FMS headers and throw em on. that, and an intake/catback should help out mpg's a bit.

 

[tktrain]

Black97mounty: FMS= Ford Motorsport, the predecessor to the current Ford Racing Performance Parts. I bought mine in 1998 when they were the only show in town. If I were starting over today, I'd definitely go with the Torque Monsters. Buy them from the forum link on this site and you can get them for about $100 off.

You may want to look at the condition of your cats, especially the rear ones. I just replaced mine with high flows on Saturday and the difference is night and day! I'll update when I have some data on mileage effects, I just reset my PCM by undoing the negative battery cable for 15 minutes earlier today.

 

[lowflyingbird]

Message For Tktrain

Hi,
I,ve been watching this link, I see you have a 98 EXPL. as do I, I'm going to change out my stainless pass side cracked welded manifold for a 99-01 cast manifold I already purchased. I did some porting work on it already.
I see you are running a E303 cam, I have this cam and plan on using it. I also see you added 1.73 rocker arms, I felt that this would be alot of lift. I'm going with the stock 1.6 as I have done on previous 5.0 Mustang builds with this cam. also in conjunction with the 1" intake spacer. What do you think I should expect? I feel that it should be just fine, with normal performance gains?
Please reply
Thanks
Keith

 

[tktrain]

Hi,
I see you are running a E303 cam, I have this cam and plan on using it. I also see you added 1.73 rocker arms, I felt that this would be alot of lift. I'm going with the stock 1.6 as I have done on previous 5.0 Mustang builds with this cam. also in conjunction with the 1" intake spacer. What do you think I should expect? I feel that it should be just fine, with normal performance gains?
Please reply
Thanks
Keith

Kieth: Note that I used the Crane die cast bolt down rockers that SVT used on the 1993 Cobra Mustangs. These are available from most of the online parts houses like Summit, and cost a bunch less than the extruded roller rockers. A big plus: they will fit under the stock valve covers! I know a few Mustangers who run the 1.7's on the exhaust and the 1.6's on the intake side.

There is a lot of debate over the 1.7 vs. 1.6 ratio rockers. The E303 has a lobe lift of .311", with 1.6:1 rockers will deliver .498" theoretical lift on both intake and exhaust (asymmetrical grind). With 1.7:1 rockers, you will see a theoretical lift of .529", while the duration will remain the same. What happens is you will see essentially the same idle quality with a higher maximum valve lift. You need to go with the matching springs, retainers, and keepers when using this cam/rocker combo, the stock springs come dangerously close to coil bind if you don't.

As far as how it will perform, this will depend a bunch on what else you have done to complement the cam. I'd start with true headers, if I were doing this today I'd go with the Torque Monsters. Then a free flowing cat back system and high flow cats (the high flow cats made as much difference on my X as almost anything I've done so far). Then look at the intake path, phenolic spacer, synthetic lubricants (especially in the front differential and transfer case), and a performance chip or flash the PCM.

My set up pulls hard from just above idle to about 5800-6000 RPM, but there is a definite chop in the idle, and the accompanying occasional tendency to die when going from drive to reverse and back while idling.

 

[bs46488]

tktrain/lowflyingbird: Here's a new question for you. Are the cast manifolds better/worst then the stock stainless? Also, will the 98-01 cast manifold fit on a 1997? Any advice?

My stainless is cracked/leaking, but I can't afford the Torque Monsters, and I'd feel like an idiot to put $300 worth of OEM stainless back on the truck.

I was going to buy headers, PCV, plugs, wires, and the 1" spacer and take apart almost the entire top end. Anything else you'd recommend throwing in while I have it apart???

 

[lowflyingbird]

Hi,
bs46488, The cast iron ones are actually an improvement, and will bolt up. Remember the dremel is your friend!! The castings are not the best, and I have improved the area within a few of the ports ,rounding out some sharp corners and poor quality casting seams. Just like you would do when porting heads. You may want to confirm any possible difference due to the newer cast peices are ment for the "P" heads with their slightly different plug angle. You will also have to plug up the newer type egr hole. I however dont think you will have a problem.

 

[lowflyingbird]

Hi,
Thankyou TKtrain for your input, In the past I have done 1.7 cast Crane rockers for the exact reason you mentioned. This time I feel the cam will be enough for me. I will also be installing the 1" spacer and replacing my cracked pass side manifold with a cast part. I will then see how it all is. As of now I have an issue with my truck not even being able to hit 5000 rpm. I'm wondering how the current cracked stainless manifold is effecting that, I'm wondering if a clogged/burnt cat might be the culprit.
Thankyou
Keith

 

[tktrain]

... I have improved the area within a few of the ports ,rounding out some sharp corners and poor quality casting seams.

My '98 came with the nasty steel tube manifolds, but I yanked them very quickly when the truck only had about 100 miles on it. We call what you did to the cast manifolds a blending job, everything you can do to eliminate restriction will help. The exhaust side is really the first place to start on one of these, as the top side is not bad as delivered from the factory. In fact, the 5.0 Explorer P heads and intake are pretty widely recognized as being the best production 5.0 parts out there. The steel tube manifolds are definitely the worst thing out there, followed very closely by the iron manifolds, the FMS/FRPP headers are a definite step up, and then the Torque Monsters are clearly the best choice.

The FMS/FRPP units aren't as high as the TM headers in price, but you get what you pay for. But I bet you can shop the FRPP dealers and find a set of FMS/FRPP units for close to $300, or if you wait, they do show up on Evilbay from time to time. The TM's weren't available in 1998, so I went with what I could get. By the way, the FMS units will really benefit from a die grinder, I cleaned up all of the welds and pieces of tube sticking into the flow path on mine, along with massaging some dented areas with a torch and an old tire iron. I must have spent 4+ hours on massaging these.

 

[tktrain]

... I'm wondering how the current cracked stainless manifold is effecting that, I'm wondering if a clogged/burnt cat might be the culprit.
Thankyou
Keith

The cracked manifolds will definitely affect the O2 sensors, I wouldn't even try to do anything else until I had a known issue like that fixed.

I found out very quickly how much failing cats affect the performance just this past weekend, the difference is astonishing. Don't forget to reset your PCM by disconnecting the negative battery lead for several minutes after fixing a problem.

About the 1.7 rockers: some of the builders like Kenny Brown used to sell a moderate level performance version of the Explorer that only had a few minor things done to the engine. One of these was putting the 1.7:1 bolt downs on the stock .421 lift cam bumping it to about .448 lift at the valves. They said it was a definite seat of the pants improvement. It's something worth considering as changing the cam in one of these is a bit of a *****, what with the radiator support being in the way.

 

[black97mounty]

Just wanted to give an update now that the vehicle is up for sale in the "for sale" section. After the intake, exhaust and new FPR, I average between 14-15mpg city and 19-20 higway mpg. Turns out the FPR was leaking as the o-ring seal had a slight tear in it. Thanks guys!

Grant