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2geepfinder

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Posts posted by 2geepfinder

    Stutter between 2500 and 3500 rpm

    in The Garage

    Posted

    My truck has recently developed a stutter... speed doesn't matter as much as engine RPM and pedal depth. When it stutters, if I push further down on the accelerator it gets worse, let up on it (but still accelerating) it gets slightly better. I think it could be running VERY rich... but I don't know.

     

    I ran injector cleaner, recent oil change and a recent fuel filter change. Air filter is a K&N with only a few thousand miles on it.

     

    Any ideas or info you'd need?

     

    PS - when it passes 3k the power picks up, and after 3500 rpm the truck surges and the stutter disappears. It doesn't seem to happen at ALL when the truck is cold, and is more prevalent in 2nd and 3rd gear without OD/TC lockup.

     

    I had this same problem the issue is the EGR valve. After I installed the pacesetter headers a noticed the stutter.

     

    Turns out, after a bit of online research that our EGR valves work off of negative pressure (back pressure) from the exhaust system which with headers and a upgraded exhaust system the majority of the back pressure is lost, at least enough that the EGR will not function properly. Our EGR valves kick in above 2500 rpm causing the stutter.

     

    To test:

     

    -In park, slowly rev the engine to verify where the stutter starts

     

    -Disconnect vaccum line feeding EGR valve

     

    -Slowly rev engine and see if the stutter is gone.

     

    This was the solution in my case. You may need to plug that vaccum line and you may also have to adjust the fuel/air mixture.

     

    A permanent solution would be to track down a positive pressure EGR and fab it up to fit; then again you could just put a block off plate in too.

     

    Have you had much like with your NTK O2 sensor?

    Dual Exhaust...... For all those who told me NO! Bite ME!

    in 90-95 WD21 Pathfinders

    Posted · Edited by 2geepfinder

    I like it!!

    I have to question your driver's seat dyno though. I'm kinda with GG on this one, for $1300 I'm sure I could pull out more ponies than dual exhaust. :shrug:

    Your math is impeccable...

    DUDE, it's a friggin 3.0 liter motor that tops out before 6k RPM!!!

    Unless you have done something significant to the intake (and cams?) more than 2.5" is probably just a waste of metal.

    You can hang 6" HVAC ducting and a fart can if it makes you happy, I just won't believe it runs better. :shrug:

     

    B

    [/quote

     

    You have to tell the whole story if your going to tell it at all............. so lets start from the top shall we....

     

    Our 3.0L motors have an intake area of 9.6211 sq. in. and an exhaust outlet area of 10.6028 sq. in. (6 outlets 1.5" dia. each with a area of 1.7271 sq.in.). The stock manifolds only have a 2" dia outlet at 3.1416 sq.in. per side which is:

    =>(1-(6.2832/10.6028))*100%)) = 40% restriction of flow just at the manifolds. Both then flow into 2" pipes then are collected into a single 2" pipe which is:

    =>((1-(3.1416/6.2832))*100%) 50% restriction.

    Overall our factory exhausts restricts flow by at least ((1-(3.1416/10.60280)*100%)= 70%. Pre cat and Muffler, so lets assume that they'll add another 10% when their new.

     

    So, right off the factory floor say ~ 80% restriction.

     

    Let's break it down into 3 options;

     

    1) 2.5" Single Pipe system

     

    Assumptions;

    Pacesetter Headers 2†collectors into 2 -- 2" pipes into 1 -- 2.5" pipe

    All calculations pre cat & muffler

     

    Calculations;

    [(1-(4.9087 sq.in./10.6028 sq.in.))*100] = 53.7%

     

    70% - 53.7% = 16.3% increase in flow……..Not bad!

     

    2) 3" Single pipe system

     

    Assumptions;

    Pacesetter Headers 2†collectors into 2 -- 2" pipes into 1 -- 3" pipe

    All calculations pre cat & muffler

     

    Calculations:

    ((1-(7.0686/10.6028))*100%) = 33.33%

     

    70% - 33.33% = 36.67% increase in flow……Better!….

     

    3) 2.25†Dual pipe system

     

    Assumptions:

    Pacesetter Headers 2.25†collectors into 2.25†pipes

    All calculations pre cats & mufflers

     

    Calculation:

    ((1-(3.976/10.6028))*100%) = 25%

     

    70% - 25% = 45% increase in flow…….Damn good!

     

     

    A couple of things to note the 2.25" Dual system is 2.25" front to back no reduction anywhere. As tight as the 2.25" pipe is I'd imagine it would be difficult to install the 2.5" or 3" without some reductions or additional bends not required with the 2.25" Dual set-up.

     

    I'd like to see some photos of the 2.5" and 3" single systems, if anyone has some post them up.

    • Like 1

    Wow what a difference!

    in 90-95 WD21 Pathfinders

    Posted

    e-bay, $108 and free shipping.

     

    I have to ask.... How did that feel?? :deadhorse:

     

    I paid less than that for 2 high flow Magna flow cats....... see www.dotcomparts.com

     

    1995 Pathy

    MSD coil

    K&N air filter

    Amsoil 5W-30

    Pacesetter Header

    Dual 2.25" Exhaust

    Magna Flow Highflow Cats

    Magnaflow Mufflers

     

    Search for Duals for pictures

     

    :tonguefinger:

    Dual Exhaust...... For all those who told me NO! Bite ME!

    in 90-95 WD21 Pathfinders

    Posted · Edited by 2geepfinder

    Here is my two sense. I think this whole set up is pretty dam sick. Even if you spent twice as much on the set up, it's all worth it to be different. For those who want to criticize you, or question what you have accomplished, don’t let em get ya down or have you start second guessing yourself. Congrats man, looks sick.

     

     

    I couldn't have said it better myself; though I don't think anyone is being tooooo critial just adding their two sense, which I like.

     

    I might be swapping in a 2-in 2-out Maganflow muffler to quite her down a couple dbs.

     

    Thanks for the support!!!!!!

     

    :itsallgood:

    Dual Exhaust...... For all those who told me NO! Bite ME!

    in 90-95 WD21 Pathfinders

    Posted · Edited by 2geepfinder

    Well if most of us use a 2.5"- 3" for singles, then you would think smaller on duals would be the way to go.

     

    Personally I don't see the point it's just a waste of extra tube, an extra muffler and space for nothing more than looks.

     

    LOL, looks, I'll dyno it and we'll have to compair it to the factory specs to see if it was all really about looks. Not that I care, in the end it was still cheaper than replacing the factory exhaust with OEM crap or something like it.

    Dual Exhaust...... For all those who told me NO! Bite ME!

    in 90-95 WD21 Pathfinders

    Posted · Edited by 2geepfinder

    Kewel. Post up some more details, would ya?

    Did you (hope not) eliminate the cats? What diameter is the piping? Prolly revs better at higher RPMS, right? Any noticeable low end torque difference? Any performance difference to justify the added expence/labor? If not its still kinda cool to have two pipes out back.

     

    Yeah, I'll post some close ups next week when I drop the tranny for repairs/rebuild.

     

    System Set-up

     

    Pacesetter Headers 70-1197 armor coated and collectors flanged out to 2.25" $355

    Magnaflow Cats Stainless 53004 Universal 3-way 2.25" x 2 $112

    Magnaflow Tru X-Crossover Pipe 10790 Stainless 2.25" $72

    Magnaflow Mufflers Stainless 4" x 9" Ovals 2.25 " 11365 $132

    Aluminized Pipe and labor $650

    Total $1321

     

    Actual revs better throughout. Low end torque has increased noticeably which = better performance. It was definitely worth every penny. If you'll notice I had the tail-pipes terminated at the body line which I like compaired to some crappy chrome tip that I would've had to clean weekly. Also, the O2 sensor was installe at the x-pipe to measure accurate ratios.

     

    :itsallgood:

    Pathfinder turbo?

    in The Garage

    Posted

    i've seen a couple of twin-turbo 300zx complete engines on craigslist for a low $400.to a high of $1500. here in the seattle area not that it does you any good. :D

    Could be big help to me that's just a short dive and I've got nice little shop just north of seatle. Thanks for the heads up! :clap:

    Pathfinder turbo?

    in The Garage

    Posted

    About a VG30DETT Swap......................Now that would be sexy!!!!!!!!!! :bow:

     

    There's been some posts on the 300ZX site I'm a member of; I thinking about doing this swap around the beginning of next year, in my 95 Pathy. So far the only issue I've read about is interference between the inter-cooler piping and the steering gear box. Not sure about the newer Pathys if they have a rack-in-pinion set up you might able to pull it off with out to much of a headache.

     

    Think about, look into then frick'n do it!!!!

     

    Sean :beer:

    Rear Washer Fluid Nozzle

    in The Garage

    Posted · Edited by 2geepfinder

    Hey, Just got my 1995 Pathy back in January it had the same "issue" here's how I "fixed"it. :idea:

     

    -Pull the third brake light out three plastic plates cover up three screws, remove them and push brake light assembly to the left it should pop out at that point may be to the right tho. If you don't have one or just pull the spray nozzle out.

     

    - Remove hose from sprayer and remove srcew attaching the sprayer to the brake light. (if required)

     

    -The easy way is to soak the sprayer peice in some type of detergent for a bit or if your careful like me you could use a little bit of brake or carb cleaner to breakdown the dirty that has cloged the sprayer.

     

    - After doing one or the other you can use a air compressor to blow the dirt out of the sprayer.

     

    - Did this and I have had no issues since even with negative temps in the Pullman area.

     

    Good luck! It not much fun but it works! :furious:

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