I recently installed a Gibson Swept Side Exhaust system on my 2000
Silverado. It really seems like I have LOST power instead of gaining.
It just doesnt seem like it accelerates as well as it did before. Has anyone ever heard of this, or is there something more I should do?
Installed K&N filter at the same time.
And I am also not too impressed with the sound. It is WAY too quiet.
Any suggestions?

Well, I'm no expert, but I have been looking for a system, researching, reading comments from all the experts or experienced out there I have read the more they opened it up with more flowthru exhaust they lost take guts, but had great top end, little better mileage. Heard that the added filter made real difference.
Myself, I'm getting ready to install Magnaflow exhaust, was thinking of the K&N dropin filter, I have 2004 LS ext. cab 2 wd and looking for alittle more sound, better mileage and if I gain top end perffomance and lose alittle of the rear end wheel spin on take off that's ok, good luck.

So far I have done this twice. :banghead: I beleive you lost to much back pressure.

If i am thinking right you will get on the highway and the truck will run like a dream. A great top end.

But when you take off and possibly around second gear shift time into second gear you have lost the pull it had?


I have also heard from a few tech guys from various places that these motors and many others are sensitive to backpressure loss.

yep...agreed

yeah, that is what seems to have happened. It lost "take off".
So, what would be the recommendation? Put the stock exhaust back on, or is there a system out there that adds sound but offers the same backpressure as stock??
The 5.3 already has enough power, as anyone that has driven one knows, so all I am really looking for is sound. I guess if I am gonna change it back or get a different one, I am gonna hafta sell this one.

Thanks for the help.

If it was me I would have kept the system stock up until the muffler since your just going for sound. Then I would of added a Flowmaster 50 series muffler with dual outs. THey have 40 series to which will sound better but are more free flowing. Then added some big exhaust tips. They help add a little sound.

I have tried the flowmaster 40 series and the Magnaflow 1in2out on my 99 back to back. For the extended cab, Magnaflow is the way to go hands down in my opinion.

I too noticed with either setup that the takeoff launch wasn't as strong, but that the top-end is a little better. This was a little disappointing to me as I was addicted to that strong launch....but at least the truck sounds like it has some muscle now...and I love the dual exhaust tips coming out the back.

I put Magnaflows on my Caddy DTS and my 93 Cobra. The Cobra loved them, the DTS lost a TON of low-end power. It seems like mufflers are always a gamble for me that I usually end up losing! :banghead:

Well, I think I am gonna put the stock back on, for now until I figure out what to do. This really BITES cuz now I am stuck with an exhaust system that I dont want.
It did everything the exact OPPOSITE of what Gibson said it would. I was confident in Gibson cuz I had one of their systems on my old truck and that one was well worth it.
Oh well, at least it is easy to change!!!

Thanks for the help. :smile:

I actual have change my mind other day, I saw a guy pulling off a magnaflow other day, talked to him about it, was not that happy, I decided on the Flowmaster 70 big block, little quiter, improves low end alittle and gived the dual out back with good sound, but tell you truth I read all these reviews about all these system and I don'r know how, but most are saying got installed from anywhere from $150 to 220, I'm not driving out of state but I have talked to 4 places, one quoted double what a set of 40 series would go for, another wanted 450, I'll end up paying $360 looks like, that's muffler pipes tips, installed taxes.

I wonder if anyone who uses a Hypertech or Superchips programmer can tell us if the yes or no questions you go through has one about free flowing exhaust? Could one of these programmers help with this low end loss from exhaust kits? Cliff

I just put a Gibson Split Rear Side exit system on my 01 Silverado. Great sound, good looks and the get up n go is still goin'.

Forgot to add... I have K & N drop in filter and removed the screen on my MAF sensor.

I have a 40 series flowmaster, single in, dual 2½ outs, and a Hypertech. Even with 285's on it, my truck will beat a HEMI out of the hole. This was before i put my FIPK on even.

I'm glad you're running good, I hope I like my FM's , ok.....about the MAF, did '04 make some changes that would make it a bad move on my 4.8 Vortec removing the screen, by increasing the flow of air, would that deliver too much cold air in winter and hot air in summer, because that thing does control the amount of air ...right? I mean the sensors sence the temp coming in, and can you remove screen without taking everything off, can you just take tube loose see it in there and pry it out? Along with the K&N, which I will get this week, does your mileage get better?

Jerry

I'm not sure, I've removed the screen in mine, but I didn't really notice a difference, so I re-installed it. I'm still debating on wether or not to take it back out since I now have a K&N, and I've been doing some research on it to see if it actually helps or hurts. As far as the mileage, I haven't really checked it. I'll be going on a pretty long trip Wednesday, so I'll post if it got any better/worse if you'd like me to.

I'm leavin it in, going with the K&N dropin, I put a torza tonneau top on the other day, man I like it, it serves it's purpose, goes on in about 2 mins. and if you take it up to the rear windown about 20 secs, no snaps just swing clamps. You know one thing I noticed about 2004, when you search for a KN FPIK it only gives you the drop in filter, but lower yerars offer the whole system, from looking at it only think missing might be the K&N filter and that's why you only need the dropin, what ya think?

What your saying makes sense to me. I'm looking on e-bay now, and I haven't seen a K&N intake, but I have seen a Volant, and an Airaid (http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=2461480808&category=38634) Both of these are great systems. Now, by reading the description for the Airaid, it says that it fits 99-04 trucks. If this is true, then the others might fit as well. There are also some cheaper "look alikes" that I've read about in another post, and the guy said that it worked well. Hell, for $39, it almost won't hurt to try. I see at least 4 of them on e-bay.