I just put LT's on my truck. That is a FACT

My truck feels slower. Thats my opinion.

Just messing with you guys about the fact/opinion thing.

I'm going to Bristol this weekend hopefully my opinion is wrong, and the truck runs better.


--I also put High flow cats on, and kept the stock catback.
The truck has a nice & quiet sound at idle and cruising, and an awful annoying sound when I'm on the gas. I guess it's the stock cat back that makes it sound bad. The only before adn after I will have is SOTP, and 1/4 mile timeslips made at different tracks with different weather. The last time I ran it was mid to lo 50's this time will be upper 70's so I quess if I'm close to my last times than it may be an improvement.

-Mike

 

When you cut the cats off or put high flow cats on the stock muffler will sound like crap and that's a FACT, LOL.

A local guy bought a used 2000 with the cats removed and 2 Flowmasters installed with no crossover pipe. He said it was really loud and sounded like crap. He bought a used stock muffler catback and put it on. It was quieter but sounded terrible above idle. I witnessed that setup.

I sold him my stock setup from the manifolds back with a single Magnaflow in place of the stock muffler. He's happy now and that's a FACT.

 

I asked Dan03lightning a while back, and he said the same thing. I still might keep the stock mufflers. I just love that quiet sound at idle, I'll try and get some sound clips so everyone knows how bad it sounds while your on the throttle.

-Mike

 

Rich and I agree on most things. I don't know if he knows that because when he posts his opinion on a topic and I agree with him then I usually don't acknowledge it.

There has been a couple of times we disagree with this being one of them. When this happens we respectfully agree to disagree without it turning into a bunch of crap. We have fun with a couple of little jabs and leave it at that.

Life it too short to get bent out of shape over something like this.

 

just wanted to thank alll of you. you have enlightened me and i now understand more about my situation. I now know what to do. Thanks

 

Mike,

I can't remember who used this description on one of the forums but he was real close to describing the sound. It sounds like a V8 boat with the header outlets in the water. If you've ever heard one of these you'll know exactly what I'm talking about.

 

Thats a good one.

 

That is exactly what it sounds like.

 

but is it a fact?

 

I just installed LT's and high flow cats with my magnaflow......My truck feels slower!!! WTF? It is loud as @#$! though!

 

LTNBOLT,

I deal with air flow, fluid flow, and SAE specs for a living. I've never run accross the *LTNBOLT butt-o-meter* as a scientific way of measuring the types of improved flow rates we are talking about.

It's science 101 that when you go from a small crossectional area to a large one, velocity slows down. It's called a difuser.

Now I'm not saying YOUR truck is producing less power down low. Maybe your stock exhaust was partially plugged? Or maybe you are flowing substancially more than the stock exhaust could take at those rpms? Therefor it may have been overly restrictive in *YOUR* case.


Case in point. Ever hear of variable valve timing? This is exactly the reason why this is done. To maximize torque (flow rates) per a given situation.

Your **impression** is not factual....Unless your a marketting weenie or a pointy haired boss. Neither of which I'll take issue with.

Rich

 

Rich,

The butt-o-meter is all that counts on the street with a daily driver, LOL.

I fully understand flow characteristics at low RPMs. I'm not new to this game. I've had a *****load of muscle cars and trucks along with 6 different sportbikes that were all modded.

The flow characteristics that you are talking about show up the most on a high RPM sportbike when going from a stock pipe to a large primary aftermarket header. I've felt it big time in the low RPM range of a sportbike.

There are several different things that affect low and midrange power. Cylinder head efficiency has a big effect on how much timing advance helps or hurts an engine. The Suzuki GXR1100's responded well to a 5 degree timing advance when doing a top gear rollon against the same bike. The Kawasaki ZX10 was hurt by the timing advance because the head was more efficient and less was better in the way of timing for it.

All the above was to let you know that I fully understand what you are talking about and to also let you know that one size does not fit all.

When I added my full exhaust at FFW in Houston 2 years ago there was no restrictions in the stock exhaust which had a single Magnaflow in place of the stock muffler. I had several mods like a 90mm MAF, Open Filter, chip, efan, SBTB, 4# Lower pulley and more I'm sure. I had my chip reburned for the exhaust the day it was put on during the FFW event. The truck felt stronger on tipin and anytime I cracked the throttle. At WOT I couldn't really tell a difference. It's hard to feel a tenth or so with the butt-o-meter.

With that being said, I do have my boost actuator set on the sensitive side and the single blade throttle body only exaggerates the quick boost factor. Anything over a very small amount of pedal results in some boost. We know that boost likes good exhaust flow.

Maybe this helps to explain my experience with the full system addon. Like I said it was all good for me except for the added volume. It was at the perfect noise level for me with just the single Magnaflow.