On thurs. I had a custom cat-back dual exhaust installed. the shop cut the existing pipes about even with the front of the drive shaft. They used 2 1/4"pipe, 2 22" glass packs, chrome tips, no H pipe and it exits out the side in front of the rear tire. It looks great. It sounds great although a little louder than I expected. It runs like sh... If you drive normally it's fine. If you stomp on it it makes a lot noise and goes nowhere(aka all blow and no go). On Friday I installed a K&N FIPK. This was a planned install not in response to the exhaust. It runs about the same. What have I done? I suspect I have opened up the exhaust too much. How do I fix it? I am open to all suggestions and a reasonable amount of ridicule and I told you so's. TIA.

------------------
Dave Sohmer
97 F-150 SC FS XLT 5.4L,Sherrod Conversion Pkg. consisting of full ground effects,running boards leather interior,wood grain dash, Cervini Cowl Induction Hood, Dual Exhaust, K&N FIPK, SportTek tonneau.

 

I may be barking up the wrong tree here but you might try disconnecting the battery for awhile to reset the computer and see what happens. You have definately lost some low end with your setup though.

[This message has been edited by ps398 (edited 06-04-2000).]

 

ps398 Thanks for answering. I had that thought myself however it was disconnected on Fri. for over two hours while I installed the K&N. I guess it wouldn't hurt to do it again. Thanks again.

------------------
Dave Sohmer
97 F-150 SC FS XLT 5.4L,Sherrod Conversion Pkg. consisting of full ground effects,running boards leather interior,wood grain dash, Cervini Cowl Induction Hood, Dual Exhaust, K&N FIPK, SportTek tonneau.

 

Kind of hoped that it would help. Two hours was more than enough time for a reset. On the other hand maybe it just needs some time to relearn. Give it awhile and see what happens.

 

Dgsohmer,

Just an idea.
1. Check the O2 sensors at the Y-pipe. Make sure they're not loose, disconnected, or wires pulled out when the mechanic was cutting and pulling on the exhaust pipe.

2. I'm not sure but check if the glasspacks are directional (in and out) like muffers.

3. Have an exhaust or emissions shop measure the exhaust back pressure. They can usually tell you if it's too restricted or open.

Keep us posted. Hope this info will help out alittle. Goodluck!!

 

Dave,

You mention that the stock pipe was cut at the front of the driveshaft - before or after the 'Y'? (I'm at work and can't run out to look). If they cut off the 'Y' and ran two 2.25" pipes you really should have the crossover 'H' pipe installed. If you look at any exhaust manufacturer's website they all mention the 'H' pipe needs to be installed with an aftermarket dual setup.

Absolutely check those things that Jupiterak suggested. Those are very good points.

Good Luck...

Tom in Tacoma

------------------
1998 F150 XLT S/C 4.6L Auto, 3.55LS, 4X2, Moonlight Blue, all the factory bells & whistles except for leather seats.

• Lund Deflector
• Lund Premier Tonneau Cover
• K&N Filter
• Body-color painted Throttle Cover
• Blue wire-looms
• Pentaliner S/R
• Window tint
• Ford side-steps
• Infiniti component speakers - front
• Polk Audio speakers - back
• Superchip (OH YEAH!!)
• Flowmaster 50 Series 'Delta-Flow' w/ 3" pipe
• Clear turn signal lenses
  
• Next up - billet grill.

Tom in Tacoma

(Washington not Toyota)
Go check out http://communities.msn.com/SS97FordsPics for the second best website for F150's

 

Checked the sensors and mufflers. There doesn't seem to be any problems there. The pipe was cut to remove the Y. There are two seperate exhaust paths from manifold to tips. No H pipe. Called the guy at the muffler shop and he said we probably opened it up too much. He said we could put more restrictive mufflers on it (for another $80. of course). He doesn't seem to think the H pipe is necessary. What do you think? TIA.

------------------
Dave Sohmer
97 F-150 SC FS XLT 5.4L,Sherrod Conversion Pkg. consisting of full ground effects,running boards leather interior,wood grain dash, Cervini Cowl Induction Hood, Dual Exhaust, K&N FIPK, SportTek tonneau.

 

I would be really wary about the shop that did your exhaust. Sure, you could always fork over the extra $80 for a more restrictive exhaust, but they are still ignoring every major exhaust manufacturer's recommendations that 'H' pipes be installed when changing over to duals.

Go take a look at: http://www.pro-max.com/flowmasterfrm.htm As you scroll down you'll see that in every instance the 'strong recommendation' that 'H' pipes be installed on dual exhaust trucks. Print that page out and take it to your shop and ask why they don't have to do it when everyone else does.

Tom in Tacoma

 

I agree with Tcolegrove, I really don't think putting a more resrictive exhaust is going to work. If you do, you may possibly loose the performance you were looking for in the first place.
I think the best bet is to have the muffler shop cut two holes in the pipe (after the catalytic converters) and have a H pipe made. I think the H pipe has something do by balancing out the exhaust pulses. I think it would cost you alot less and buying more mufflers.
I just hope you kept the original Y pipe for backup measures. good luck.

 

an x pipe is the best way to go ..seems that the x is the best performing set up....

 

Where do you put the "H"? It's my understanding that you can't just stick it anywhere and get the benefits. Should it be 2,3,1/2, ft. back from the cats?

The "X" pipe really is supposed to be best, but where they join is critical to their function too.

 

You may be running too small a pipe diameter also. I've never seen a 5.4L without 2 1/2 pipes. You may be choking it.And I would agree on the H or X pipe.Definitely need one, but no idea where the best location is. Usually they are just after the cats.

 

I was once told that if you spay paint the exhaust and drive for a while, where it starts to burn off is where you put your X or H pipe. I guess this puts the crossover in the best place for the torque curve. I learnd that in the "old school" days. Just my .02.

------------------
1999 4.6 Extra Cab-Short Bed
Silver Clear Coat Metalic
K&N Airfilter
17 Inch 2000 Chrome 4X4 Wheels Wrapped in 275/60/17 ZR Yokahama AVS
White-Faced Luminescent Gauges
Flowmaster 3 inch Cat Back 40 Series Exhaust
3.5 Inch Polished Thermal Research Exhaust Tip
Clear Corner Lenses
Super White Headlight and Turn Signals
Trends Billet Antenna
Stull Billet Grill
e-mail SILVERFORDF150@AOL.COM

 

The paint technique that FordTrk posted is absolutly correct. If you do not do this and connect the two pipes somewhere, you most likely will not receive much of a benefit, if any at all. That is how all the exhaust specialists I've talked to do it, and it is a practiced art with some of the best.

------------------
I am the driver of BIG RED! '99 S/C, 4.2, 5 spd, XLT, Bright Red Clearcoat, Medium Graphite, 5 Spoke 16" Cast Aluminum wheels, Lund bug shield, Limo tint, Pendaliner.

Aim Screenname : Qwikranger

Audio:
Pioneer DEH-345 Head Unit, Infinity Reference 5x7's all around, Kenwood KAC-848 50x4 amp on them, MTX Thunderform loaded with two MTX 6000 8's, and an MTX Pro 75 x 2 Blue Thunder Amp on those beasts.

Things I want:
1. Exhaust
2. Airaid intake
3. Superchip

Limiting my performance increases:
1. BEING A COLLEGE STUDENT!! $$$

Join AllAdvantage.com and make money surfing the web!

 

Thanks for the paint info. I'd never heard that one.