Thread: New mods

Hey guys, I'm am hopefully going to be modding my GTP over the winter. Gonna be adding a cat back exhuast, 3.4 pulley, cold air, and upgraded PCM...any ideas of what my hp rating will be after those mods??

You'll need to do more on the exhaust side of things besides just a catback to be able to run that 3.4. Ideally headers.


I'm not good at hp questions so maybe some one else would chime in.

What is the best way to start off mods in your opinions???

fenderwell intake. easy makes your car sound badass and adds some get up and go. its kinda hard to tell on mine how much cause its snowy in alaska so i cant get much grip but its fun drifting but yeah mine was eighty bucks for the abs pipe, elbows, couplings, and the K&N Air Cone cheap and easy to do.

open cone intake (you dont need a FWI or a fancy intake there is no advantage unless you are sitting still), downpipe, used modded 1.9 rockers. You can do what you want with the pulley without the downpipe the 3.4 will hurt you more than help. But prolly wont blow anything up. alot of people back before scaning and programmers were popular ran 3.4 with nothing more than intake and ubend del.

Originally Posted by Dawings33

open cone intake (you dont need a FWI or a fancy intake there is no advantage unless you are sitting still),

I promise you're wrong about that. I have tests to prove it.

Yeah well it's one of those things that no one will ever prove wrong or right. I have the tests put not the proof. So i correct my self on that.

But if you can say the temp difference of AT LEAST A MINIMUM OF 20* in air doesent give you Some kind of power increase or advantage then I'm going to go ahead and take my intercooler off.


Just like some people say an open cone gets more flow.....Able to flow more? Sure. Does a 4'' fenderwell intake restrict flow needed for an 11 sec 3800? no.


Either way... I think the both of you are pretty damn smart from what i've seen. So not trying to insult anyone.

I personally dont care what people think, but there has been test done to prove the open cone theroy as well. People can argue all day long how much of a difference temp will make but it has been proven that a open cone will yeild higher MAF numbers ie higher airflow into the blower. Dave P. (dezdave) has the numbers on all the test he ran)

Originally Posted by Dawings33

has the numbers on all the test he ran)

And so do I. Funny, because if thats the case then we just proved each other right. And we can't both be right.



I guess the next test are going to be to prove wich is more of a gain. That little extra air flow.....Or the 40+ degrees of cooler air.


Whatever.....


The higher MAF numbers were probably the tranny slipping off of it's ass when when it was suppose to be shifting.

In regards to the cfm data from zzp-

They do not correlate to any specific HP amount or cfm in the car. We simply set up the flow bench to flow at various vacuum levels and tested a variety of intake pieces to determine where most of the restriction in an intake system comes from.


Exactly what i was saying. All these numbers show are that with a 90* bend in a 4'' pipe the flow will decrease.....No ****.


And with the MAF screen out the flow will increase....no ****.


What they don't show is how much cfm's a car that is running 11's needs. AND how much cfm's a 4'' pipe at a said length CAN flow in cfm's.


Thats what needed to be done.


Wich brings back my point.


Originally Posted by TDCRacing
Just like some people say an open cone gets more flow.....Able to flow more? Sure. Does a 4'' fenderwell intake restrict flow needed for an 11 sec 3800? no.



Someone else prove me wrong.


Bottom line is I know how many cfm's my car needs with the amount of hp i have. And A 4'' intake can flow WELL WELL beyond that.


If some one would like the info i can try to dig up the almost 2 hours of formulas and conversions that i went through so i can prove my point.

This is not something worth fighting over.

Originally Posted by Bio248

yeah, i know. i just figure im throwing it into the blower anyway so no matter how hard i try and cool it beforehand it will still just heat it back up.

i gave up on it.

I know what ya mean man, I think of it like this though,


If you can get the air into the blower 20* cooler then the air out of the blower should be 20* cooler. Maybe i'm thinking of it the wrong way.


But i'd imigine at a said rpm and iat temp that the blower will be producing outlet temps at a steady X temp also. Well if you reduce the inlet temps at all the same levels as said above by 20* it seems is if the outlet temps would also decrease.

Now maybe it wouldnt be exactly 20 degrees but i'd imagine it would be at least 50% of that.

Maybe i'm just thinking about it in the wrong way though.

Originally Posted by Dawings33

This is not something worth fighting over.

Wel, i'm not mad at all. Just having a friendly discussion in my opinion. I'm sure you're on CGP and i know you're new to THIS forum, But here typically everyone gets along here. So you don't have to worry about threads like this getting out of hand over here.


Usually everybody in the discussion learns something new any way.



But going back to what you said....


---Quote---
Idk ZZP has done some testing that says otherwise.
---End Quote---
CFM using 1 inch of vacuum
(higher numbers indicate more flow)
238 5" of straight 4" PCV
220 26" of straight 4" PVC
183 Above tube with added 90 deg bend
205 9" long 4" inlet dirty K&N filter
227 9" long 4" inlet clean K&N
181 7" long 3.5" inlet clean K&N
168 LS6 MAF with screen in
191 LS6 MAF w/o screen
159 26" PVC, 90 deg bend, LS6 MAF (no screen), 9" K&N
94 Stock GT TB with screen
104 Stock GT TB w/o screen
107 Stock GTP TB with screen
119 Stock GTP TB w/o screen
123 S1 GT HVTB w/o screen
138 S1 GTP HVTB w/o screen
from zzp site

seems the shorter intake tube flows better other than that anyone can use what they belive is best for their applications

.................................................. .................................................. .........................

Like i was saying....I realize a shorter tube or one without a 90* can flow BETTER but that better flow is not NEEDED with our cars.


In other words what im saying is that our cars can never out flow a 4'' pipe...Nothing in the 11's anyway.


Maybe i did the math wrong....If so i would love to be corrected....Shoot if i could take the intake off of my car and put an open cone and gain HP then i'd also love to do that