Plenum/TB setup worthless on nearstock car?

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
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Massachusetts
Gotta start somewhere right? Been thinking of a plenum/TB setup for my GT which is stock except for a flowmaster cat-back.

Would i even notice any gains with a plenum and 70/75mm TB? I am not planning on swapping the mid-pipe anytime soon. Is it even worth the $300-350 or should i just home port up a spare plenum i have and leave it at that?
 
general consensus is the plenum will give u a few horses, 75mm tb wont do anyhting for ur stock engine

for only a few horses i would home port ur spare and save a few bucks to see what itd grant you

correct me if im wrong please
 
Any site on the self-port.


If i do aftermarket plenum, it would have to be accufab since they supposedly give the best results.

But i am trying to convince myself $350 for a plenum/70mm TB is worth it when i am not doing any other mods (yet)
 
Wow i thought you wer eleaving it stock. The mod bug gets everyone even you!!! I think the CAI is a way better investment than the TB/Plenum if your going to do anything. I felt the difference witht k&N FIPK and i would also think an xcal2 would be a better investment than a tb/plneum

Joe
 
Mustang5L5 said:
Any site on the self-port.


If i do aftermarket plenum, it would have to be accufab since they supposedly give the best results.

But i am trying to convince myself $350 for a plenum/70mm TB is worth it when i am not doing any other mods (yet)
The plenum/TB test Mod Depot did showed accufab to be the best but only by a slight margin. All were within @ 1hp of each other so it comes down to price when choosing. Also lots of used sets for sale from guys going KB etc..heres a set i came across today on Corral..Trick flow plenum/FMS 70mm TB for $190. I'm sure he's negotiable :) ...just another option.
http://www.corral.net/forums/showthread.php?t=788308

Oh test results were like 5-7 rwhp for tb/plenum on stock 4.6 if i remeber correctly.
 
streethorse said:
You will need all three, CAI, TB, and Plenum to feel a
difference. My guess would be a 10 to 15 hp jump,
better throttle response. At higher rpm is where it all
happens.


thats funny, I didn't have a CAI and I put the T/B on by itself for a few days before installing the plenum. I felt both mods individually, nothing huge, but things were "smoother"
 
it is not wothless but at the same time it is not the mod to do first IMO.

gears are more noticalbe, my o/r x-pipe was more noticable. those are mods in the same price range.

so I would not do it first. It is by no means a night and day mod to the car. I spent $300 on my accufab plenum and tb off ebay used. it helped but I will say that

gear, midepipe, subframes, lca's are all better mods for the money. I would not buy plenum and tb untill those mods were on my car if don't it over again.
 
myponyrocks said:
thats funny, I didn't have a CAI and I put the T/B on by itself for a few days before installing the plenum. I felt both mods individually, nothing huge, but things were "smoother"

Yeah, I did mine 1 at a time also starting with Mac CAI, then C&L Plenum,
Then last a 70mm Ford racing TB, I could notice the difference with each mod
but wasnt very impressed until I added the TB, then I was satisfied since it
all added up to a pretty nice kick in the a$$ :nice:
 
Well i don't want to do gears. It's my daily driver and i do a lot of highway driving so i like the 3.27's. I like doing 1900RPM at 75MPH on the highway.

Also i don't plan on drag racing my car so not looking to squeeze every little tenth i can out of it. I'd do the mid-pipe but i don't want to deal with swapping it every year for a sticker and the excess noise. This is my daily driver.

I just am looking to gain a few more ponies up top as i like to wind out the gears on the highway.
 
Mustang5L5 said:
Well i don't want to do gears. It's my daily driver and i do a lot of highway driving so i like the 3.27's. I like doing 1900RPM at 75MPH on the highway.

Also i don't plan on drag racing my car so not looking to squeeze every little tenth i can out of it. I'd do the mid-pipe but i don't want to deal with swapping it every year for a sticker and the excess noise. This is my daily driver.

I just am looking to gain a few more ponies up top as i like to wind out the gears on the highway.


if you put it that way then go ahead and get the 75mm T/B and plenum :shrug: but its all on you though
 
XtorT'r said:
I just added a BBK 70mm tb and an Accufab plenum and redynod. Before I had them add my chip the plenum only gave me 1rwhp. I also found out there is like 7-8rwhp to be had by upgrading your catback.

Catback is only good for 1-2WHP ;) . MIDPIPES give you about 7-12WHP...

5L5-just get a Xcal2 :nice:
 
the98stang said:
Catback is only good for 1-2WHP ;) . MIDPIPES give you about 7-12WHP...

5L5-just get a Xcal2 :nice:
Nope sorry, I'm never believing that again. I have no idea where people got that from. After I already had long tubes and Prochaber and all my other mods my numbers were at 262/297 which was repeatable. We exparamented to test the 1-2 rwhp gains theory on the same day and found that I got up to 7rwhp and 6rwtq with out stock muffs.My tuner did not touch my tune in between runs either. There is a small amount of power to be had there.
I would have purchased a catback years ago if I hadn't been listening to this 1-2 rwhp nonsense.
As far as I am concerned it has been dyno proven to me infront of my own eyes. Perhaps mustangs of different years had better flowing Muffs, mine apparently does not flow well.
That also explains why I have been seeing guys up by me having CAI, plenum&tb, tune, pullies, and catback making 250ish on the same dyno I use.

I'd be more likely to think it was error if it was on a different dyno and if we had been messing with air temps to skew results.

Last dyno before swapping to a mufflerless system
4/27/2006 11:08:49 AM Run Type RO Run Conditions: 74.48 F, 29.15 in-Hg, Humidity 7%, SAE 1.00
Max torque = 297.59 Max Power = 262.50
Dyno after I ditched fords poopy muffs
4/27/2006 11:18:32 AM Run Type RO Run Conditions: 75.32 F, 29.15 in-Hg, Humidity: 7%, SAE 1.00
Max torque = 303.45 Max Power = 269.29