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cobra330
10-04-2004, 09:58 PM
I have what I would call back fire sound in my exhaust. This only happens at deceleration (sp). So basically go up through the gears..mainly 1 through 3rd. Then slowing down in any of those gears after reaching highway speeds I seem to get a back through the exhaust. I have Flowmasters which are about 3 years old and MAC Hi-Flo Exhaust which is about 2 months old..maybe 500 miles. The only other mods to the motor are UD Pullies about 1 month old with 250 miles..and WMS CAI..1 year old.

I probably do need to change the spark plugs and wires but, do I need a computer tune...maybe like the chip in the car flashed with a new program?

tcrews
10-04-2004, 10:04 PM
You're running a little rich and that's why it's backfiring/popping. A chip would fix it but that's a lot of money for nothing... You might gain a few extra HP but with the mods you have it's really not worth it. A mail order chip won't do it so you are looking at a dyno-tuned chip....figure about $500 for the chip/tune plus whatever you have to pay for dyno time (typically $100 per hour).

cowboyharry
10-04-2004, 11:16 PM
Hey mine kinda rumbles and pops when I let out off it too. But dang , I sure like that sound. Dont tell me it aint supposed to do that. :) :( :p :eek: :thumbsup:

casey99COBRA
10-05-2004, 01:44 AM
nothing to worry about.

cobra330
10-05-2004, 09:38 AM
You're running a little rich and that's why it's backfiring/popping. A chip would fix it but that's a lot of money for nothing... You might gain a few extra HP but with the mods you have it's really not worth it. A mail order chip won't do it so you are looking at a dyno-tuned chip....figure about $500 for the chip/tune plus whatever you have to pay for dyno time (typically $100 per hour).


So when you say chip/tune..they are basically tuning the my current computer program..or are you saying they would replace that chip? WOW! So, were talking about $600.00? Yikes. Is that going to hurt my car by running rich?

tcrews
10-05-2004, 10:43 AM
So when you say chip/tune..they are basically tuning the my current computer program..or are you saying they would replace that chip? WOW! So, were talking about $600.00? Yikes. Is that going to hurt my car by running rich?
Do you currently have a chip? Is it a mail-order generic chip? You may want to pull it as it may be the cause of your problems. If you already have a chip they can reburn that if they use the same type (autologic - autologic, superchips - superchips, etc...). Cost will be a little less but not that much.

Running a little rich won't do any harm, running a lot rich (lots of black smoke coming out the tailpipes) can destroy your cats and will cause a reduction in MPG and power.

cobra330
10-05-2004, 11:13 AM
Do you currently have a chip? Is it a mail-order generic chip? You may want to pull it as it may be the cause of your problems. If you already have a chip they can reburn that if they use the same type (autologic - autologic, superchips - superchips, etc...). Cost will be a little less but not that much.

Running a little rich won't do any harm, running a lot rich (lots of black smoke coming out the tailpipes) can destroy your cats and will cause a reduction in MPG and power.

No chip...Sorry I guess that should have stated the original computer program..no after market chip though.

No black smoke coming out at this time. Thanks for your help! It just started worrying me...

Abneriel
10-06-2004, 10:58 PM
you can lean it out a bit by taking off the screen connected to your MAS...

cobra330
10-07-2004, 09:43 AM
Just by removing that screen? Hmmm..I may try that. That's a pretty easy fix. Thanks!

ausie
10-07-2004, 01:07 PM
If you have issues after removing the screen, make sure you line up the mesh in the same fashion it was before you remove it. I had removed mine for a trial and it caused too much of a lean condition (too much pinging). When I put it back in, the pinging did not go away (it was not as bad as it was without it though). I read somewhere that the alignment of the wires in the screen were at any other angle in relation to the MAF sensor pipe in the meter you may get some dips in the A/F mixture (muscle mustangs and fast fords). The mesh should line up with perpendicular and parallel (vertical and horizontal) to the sensor. Just an FYI

cobra330
10-07-2004, 01:20 PM
If you have issues after removing the screen, make sure you line up the mesh in the same fashion it was before you remove it. I had removed mine for a trial and it caused too much of a lean condition (too much pinging). When I put it back in, the pinging did not go away (it was not as bad as it was without it though). I read somewhere that the alignment of the wires in the screen were at any other angle in relation to the MAF sensor pipe in the meter you may get some dips in the A/F mixture (muscle mustangs and fast fords). The mesh should line up with perpendicular and parallel (vertical and horizontal) to the sensor. Just an FYI

Thanks!

On a side note..where did you get your BBS Plasma Rims...? I want those for my 04!

ausie
10-08-2004, 09:20 AM
I got the wheels as a complete wheel package deal through tire-rack. You can find them at other wheel/tire sellers over the net. The prices vary. Tire-rack had both the wheels and tires I was after (even though the wheels were slightly higer, but the savings in the tires made it a no brainer. I saved about $400.00 over another site that had both. Due to changes in pricing always compare. The last time I looked at tire-rack, the cost of the wheels went up $150.00 after I bought them.

cobra330
10-08-2004, 09:49 AM
I got the wheels as a complete wheel package deal through tire-rack. You can find them at other wheel/tire sellers over the net. The prices vary. Tire-rack had both the wheels and tires I was after (even though the wheels were slightly higer, but the savings in the tires made it a no brainer. I saved about $400.00 over another site that had both. Due to changes in pricing always compare. The last time I looked at tire-rack, the cost of the wheels went up $150.00 after I bought them.


Thanks! What tires did you go with? What size in the rear?

ausie
10-10-2004, 01:18 PM
(way off topic here, just answering the q) The tires are 275/35 18 in the rear end and 245/40 18 up front. I got the Bridgestone Potenza Pole Position S-03 wrappers since I loved them when I put them on the stock wheels. Those were the best tires I ever had on the 01. When compared to the original 01 tire size the rears were 1/2 inch shorter, but compared to the 04 tire size they are 0.08 inch shorter so the MPH is where it should be. I run about 39PSI to 40PSI in all 4. They grip like glue but they also track the road surface a bit more than stock rubber. They now have 10k miles on them and I swapped them for the stock 04 wheels. Even though they are worn a bit, they are several grades better than the Goodyear F1's.

Back on topic, More than likely if you think it sounds like a back-fire when letting off the gas, it is probalby due to unequalized pressure differences from throttle to idle in the exhaust. My 01 made some really nice sound when letting off the gas. I really miss that sound, music to my ears. My 04 is whisper quiet, all I hear is the whine of the Eaton either sucking in the air like a Boeing 737 (if there is such a thing) under boost to a pissed off cricket under no boost. I got spoiled with the SLP on the 01 and I am not a happy camper that I did not take it off before I got pricing on an 04 :drool: (since I took the 04 home that same day). Looks like another cat-back purchase is in order. :edmond:

cobra330
10-10-2004, 07:30 PM
ausie

Thanks for the info! Yeah...my 04 is so freaking quiet..and I just got the exhaust set on the 98..and now I gotta do it all over again! Oh well...what else would I do if I did not spend money on my car!

I see you are in Allentown..let me know if you go to any shows up that way...I may come up and meet you! Also..you going to Carlisle in 05? The all Ford weekend??

ausie
10-11-2004, 08:31 AM
I go to as many shows as I can. I missed the one in Coopersburg this year due to rain. I have friends who were vendors at the show and they called me up and told me it was canceled. It turns out they had the car show, but only canceled the vendor part of it.

I usually attend the monthy Wheels of time Cruise Nights at Machungie Memorial Park. The last one of the year is this weekend October 16th from 4pm till 8pm. If you go, I will have a Silver 04 with BBS RK plasma wheels. Also I will be displaying my video work from the previous shows and some from the Island Dragway in NJ (my friends and I frequent there on Fridays, I have yet to make a run down the line but will definately have to next year just to see what the 04 will do in stock flaovor).

I am going to try to get the SLP Loudmouth ordered today at work and see if they have any in stock and if I can get it before the show. I will just have to see how it goes.

I will go to the Carlisle event. Do you have the dates and location? I am sure I can get some others to go down too since It is more fun to have a convoy of mustangs on the loose (that way we all get speeding tickets at the same time :rotf:

cobra330
10-11-2004, 09:55 AM
I go to as many shows as I can. I missed the one in Coopersburg this year due to rain. I have friends who were vendors at the show and they called me up and told me it was canceled. It turns out they had the car show, but only canceled the vendor part of it.

I usually attend the monthy Wheels of time Cruise Nights at Machungie Memorial Park. The last one of the year is this weekend October 16th from 4pm till 8pm. If you go, I will have a Silver 04 with BBS RK plasma wheels. Also I will be displaying my video work from the previous shows and some from the Island Dragway in NJ (my friends and I frequent there on Fridays, I have yet to make a run down the line but will definately have to next year just to see what the 04 will do in stock flaovor).

I am going to try to get the SLP Loudmouth ordered today at work and see if they have any in stock and if I can get it before the show. I will just have to see how it goes.

I will go to the Carlisle event. Do you have the dates and location? I am sure I can get some others to go down too since It is more fun to have a convoy of mustangs on the loose (that way we all get speeding tickets at the same time :rotf:

I will have to check the Carlisle website to get the dates. I will get back to you on that one as the time gets closer. Check out the website..http://www.carsatcarlisle.com/schedule/2004.asp

Also, not fimiliar with Machungie Memorial Park..that sounds interesting. Where is it?

ausie
10-11-2004, 11:17 PM
I will check that out. I heard that Carlisle has a big show down there.

It all depends on where you are comming from. If you are comming up from Carlile or in the Harrisburg area, that would be a long drive (80miles +)

If you are interested: (note if it rains, it will get canceled like it did every month except for April, May and June.)
Machungie is on Rt 100 south of I-78. Traffic may be heavy in Trexlertown due to the rt 222 bypass construction. Go straight through that light. You will also be passing MACK trucks assembly plant on your right. When you hit the town of macungie, you will know it since it will be the only set of train tracks that has more than one set crossing the road (beer distributor on one side and what used to be a 7-ll on the other both will be on the right side of the road), look for the sign on your left (it will be before the subway shop which is also on the left). The park is one block east of rt 100. The show is from 4pm to 8pm. Not a long on this time. Machungie usually gets a large handful of vehicles (typically on a good day the park is filled with 200+ cars) Entry fee is just a dollar donation (unless you want to pay more, I usually give in $5 since it goes to some foundation of some sort). You will find more big block street rods there but there are a small group of us new age muscle car people there as well as the average classics too. Much of the cars I have seen there really are not street leagal (but that's what it is all about right?) Once in a while they have a live oldies band playing music. The last event I went too that was not rained out, they had an elvis impersonator on stage.

Before I forget, If you do got to the show, the cops are sticlkers with the speed limit. Over 35 you get a ticket. It is not as bad as leaving the drag strip in NJ (island dragway) but they will get ya if you are speeding (only if they see you that is)...:D

ausie
10-11-2004, 11:22 PM
Here is the association web banner with the August show information. They may have better directions or a map.

http://www.wheelsoftime.org/jamboree.shtml

cobra330
10-12-2004, 09:20 AM
I will check that out. I heard that Carlisle has a big show down there.

It all depends on where you are comming from. If you are comming up from Carlile or in the Harrisburg area, that would be a long drive (80miles +)

If you are interested: (note if it rains, it will get canceled like it did every month except for April, May and June.)
Machungie is on Rt 100 south of I-78. Traffic may be heavy in Trexlertown due to the rt 222 bypass construction. Go straight through that light. You will also be passing MACK trucks assembly plant on your right. When you hit the town of macungie, you will know it since it will be the only set of train tracks that has more than one set crossing the road (beer distributor on one side and what used to be a 7-ll on the other both will be on the right side of the road), look for the sign on your left (it will be before the subway shop which is also on the left). The park is one block east of rt 100. The show is from 4pm to 8pm. Not a long on this time. Machungie usually gets a large handful of vehicles (typically on a good day the park is filled with 200+ cars) Entry fee is just a dollar donation (unless you want to pay more, I usually give in $5 since it goes to some foundation of some sort). You will find more big block street rods there but there are a small group of us new age muscle car people there as well as the average classics too. Much of the cars I have seen there really are not street leagal (but that's what it is all about right?) Once in a while they have a live oldies band playing music. The last event I went too that was not rained out, they had an elvis impersonator on stage.

Before I forget, If you do got to the show, the cops are sticlkers with the speed limit. Over 35 you get a ticket. It is not as bad as leaving the drag strip in NJ (island dragway) but they will get ya if you are speeding (only if they see you that is)...:D


Just so you know...I would be coming from Maryland through Harrisburg so, it would be a lllooonngg drive. I probably won't make it this year..maybe next year. Maybe we can meet with SCMC group meet. Get the MD/PA/DE people together?

Carlisle...is HUGE! You should go next year...more mustangs/cobras..etc...than you can shake a stick at..and lots of parts to spend money on!

ausie
10-13-2004, 07:25 AM
The wheels of time meets once a month, it is mainly Street rods and classics. There is a local chapter in the area that has a meet once a year which is the First Pennsylvainia Mustang Club which are an SVTOA group. Fully jundged event in August. And there is the Ford weekend at Maplegrove Raceway in the Reading area usually in June (which seems to get rained out every year I want to attend). I definatelly will go to the Carlisle event this comming year for sure.

I would be interested in going to an SCMC event if it was not way too far out.

It looks like rain this weekend so it may be rained out (again). It probably would not be worth the trip this time. I will keep a look out for the next schedule of the Carlisle show. Thanks for the site!

cobra330
10-13-2004, 09:41 AM
Thanks for the info!

I will get back to you about a SCMC meet..still trying to work it out.

Yeah Carlisle is around the same weekend as Maple Grove I think..they both get lots of rain! Hope to see you there in 05!