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airflow performance upgrades

BLUTO

NAXJA Forum User
Is anyone here running one of the throttle body spacers? If so, we you pleased with it's performance and what brand is it? Does yours have the "threads" in the I.D. of the spacer to "create a swirl flow-pattern?
Is anyone running the Flowmaster 50 series (3 chamber) muffler? Pleased? Did you notice any resonance in the interior?
Thanks for your input,
BLUTO :)
 
I've had the 50 series(3ch.) for a couple of years now. I think it has a good sound(some disagree). There is some resonance. I think it's at around 2K. I usually have the tunes blaring. A loud stereo helps. For the most part, I am pleased. Although, there is the occasional time I wish I had a quiet exhaust. People WILL hear you coming. So, if you're planing covert ops, this is a poor choice of 'muffler'.

I don't have any first hand experience, or expertise with the TB spacers, but this is what I had read . . .
They might make a little bit of difference, but not much. A bored out Throttle body is better. As for the vortex thingies, since the fuel is shot into the cylinder(on the MPI), it apparently shouldn't provide any real benefit.
 
Flowmaster vs DynoMax

Thanks Lou,
I had some (LOTTA !) resonance on my 360 V-8 Dodge truck w/FlowMaster 3-chambered mufflers. Does anyone know if the DynoMax system is decent flowing without the resonance?

An engineer at work told me that the phenolic spacer kits may work because they help "insulate" the throttlebody from engine heat. Is boring-out the throttlebody a difficult (costly) job?
Thanks,
BLUTO :)
 
There's a few places that'll bore 'em out for you. Usually you send 'em yours for the one they send you. Check out Jeepers and Creepers at:
http://www.jeepersandcreepers.com/gear/pages/throttlebody.htm
Rubicon has larger throttle bodies for sale, but they're another $100 (J&C is $235 minus the core charge).
I haven't done it myself, but coupled with a freer flowing exhaust lots of people say it's the best performance mod they've made.
 
Dynomax Super Turbo

I have had 3 DynoMax cat back systems on an 87 and 89 and they are relatively quiet - they get noiser if you replace the stock cat with a Hi-flow (catco) but still quiet at cruise. Even with the stroker its louder with power on but quiets down at cruise.
I've never seen someone removing a Dynomax super turbo because of excessive noise - seems every few weeks someone is removing a Flowmaster!
 
I have had a PowerAid TBS with the helical bore on since January and though I didn't really notice the mileage gains I was hoping for on my drive back up to school from VA to way upstate NY, I could feel a slight power difference on the highway. It is a really easy install, but there is a problem, if you are ever planning on getting an air tube I have heard that you can only have one or the other, haven't tried it but that is my warning. The PowerAid does whistle the slightest bit when you really get on it (it's kind of cool actually, almost makes it sound like I have a turbo).

As for the muffler, I'm running a Gibson system and I am impressed with it, although that doesn't really help you with your Flowmaster decision
 
Anyone running a thrush Glasspack? I am redoing my exhaust next week and have yet to decide on a muffler, but I can't see sinking a lot of money in on one, just to meet a rock the first time back out! The 4.0 my friend had sounded good on his wrangler... I am assumming it shouldnt be any different. He either has glasspack or Flowmaster. I just don't want my rig sounding like a weedwacker.
 
I tried an airaid TB spacer and all it did was make noise, a deffinite waste of $$$ in my opinion. Boring your own TB is easy and should cost less than 20.00 and you'll finish in under 1 hour. www.gojeep.rockcrawler.com will show you how to do it your self.
 
Better Breathing

Thanks for all your input guys! I will probably go with the DynoMax Ultra Flo's (maybe thru Rusty's), I'll see what my local supplier can do 1st. I was concerned about the fiberglass burning out in time (flowmaster doesn't use it).
I went to Go Jeeps website (lotsa good info from "DownUnder"). He mentions that resonance is set-up due to the exhaust gasses slowing down in the tailpipe (due to them being cooled) and suggested sizing down the tailpipe to keep their velocity up. I will consult our "Flow Test" people tomorrow at work (DaimlerChrysler Tech Center). I will also ask if they can bore-out the TB for me too.
I may still go with the TB spacer if I can get the materials here and build it myself....since I'll have to bore-out the spacer to fit my bigger TB anyway ;) . I may look into fabbing ram-air kit for the stock airbox while I'm at it. Or using Rusty's tube and damming-off the intake from the "under-hood" air.
Thanks again,
BLUTO :)
 
Homebrew Spacer and big bore T/B!

I did make a T/B spacer, had to try somethin wasn't ready for gears and have 3.07's! When I started, I purchased 1" bar stock for $2.00 and cut the hole 60mm around. Then polished it. Bolts purchased at ACE for $1.60. Gaskets for nothin from dealer, ( I work There!) Went to put it back on and noticed that the spacer was way bigger than the T/B. Decided to machine out the throttle body to 60mm. Put it all back on and ran it in driveway. Noticed that the airbox was actually flexing under rpm! Took the airbox apart and took out the restrictor, put in K&N filter extra from my 96 Ram truck (same filter). Big difference in low end torque a little top end power and a lot of air noise! Was worth the 2 hours and $3.60 to me!
 
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