I am thinking of adding some headers and high flow cats to my truck. I was wondering how much it would help out, is there a big seat of the pants difference. My current best time is 12.87 in 75 degree heat. How much do you think the headers would improve that? I have also heard that adding headers will decrease your boost by 1-2lbs. Is this true? I was also thinking of adding the 2 lb upper pulley. Please give me your suggestions on this, my truck is a daily driver, Will this be a safe setup?? Thanks for all your help!!

P.S.- I am talking about the Kooks Long Tubes

 

I can't claim I noticed a difference in the seat of the pants, probably due to the fact I completed a number of mods at the same time including dynatech longtubes and highflow cats. Yes, it is true I lost one lb due to the free flowing exhaust.

I chose that route due to the KB purchase and I was seeking a free flow more for efficiency than anything.

Note: your exhaust sound will change completely and you need to be aware that even though you can get alot of growl out of our stock system with a cat back, when you go longtube and highflow cats it is a totally different sound. Not for the tame at heart. Mind you I love mine and everyone who knows anything about engines appreciates the note.

Hopefully someone who has dyno'd a before an after will respond. Good Luck!

D-Day

 

Yeah i would say go for it if you are planning on doing more mods to your truck in the future. Also the sound is unbeatable. I felt a seat of the pants difference.

Zach

 

Don't do the #2 upper...belt slippage, could damage the supercharger, need special tool $$, if any thing go bigger on the bottom, but #4 is pretty much safe for stock bottom with a good tune.

 

I'm also very intrested in this post, since JJ just put on my Dynatec long tubes and Bassani's just last week.. I know its louder, but faster ???? We will see. Hope some will give us some dyno results.....................

PEacE.....................
Jim

 

ttt

 

JDM Claims 30-40 hp gains and 40-50 torque gains. I am wanting some big power gains, I can't see dumping $1500 into this and not getting much power in return. Any more help would be appreciated!

 

You guys have any more help on this one....

 

I need headers and high flow cats......especially with my setup..but I dont want my truck any louder than it is now.

But I cannot decide what to do....I need the free flowing and the extra power..but dont want the noise.

 

Me too

 

Suck it up and get the damn LT.

 

I went with just the hiflow cats and it is definately louder. So if you don't want noise keep the stock system. I say if you got the $$ go for it and don't worry about the noise.

 

It will be much louder....... I swear.............

PEacE....................
Jim

 

I thought that the LT only helped out significantly with the people that were pushing higher boost. Seems like a lot of $ for just the sound.

 

as I have repeated many times:

my long tubes gave short peaks of as much as 20HP on an otherwise 100% bone stock truck with less than 1000 miles on the odometer.

the average HP gain was between 10 and 17hp if I remember correctly.

now the TORQUE on the other hand gained 30FT/LBS ACROSS THE ENTIRE RUN!!!!

here's the thread:

Dyno day #2 for the Blue Goose -or- Stock '03 -vs- JDM full exhaust '03 numbers

later,
chris

P.S. as a side note, it seems like I constantly have exhaust leaks, either at the collector, or at the cyl head/exhaust flange. one thing to consider, I hate it.