Pulley question


CmdrDCM

Member
Oct 1, 2022
16
Duluth MN
I hope I am not asking a question that has already been flogged on the forum but this is my first post so be kind. I acquired my 2006 GT in February. I am the third owner and I have virtually no information about the first owner and whether he made any modifications to the car. Specifically, how can I tell if the SC pulley has been changed from stock? Thanks for any help!
 

nota4re

GT Owner
Mark IV Lifetime
Le Mans 2010 Supporter
Feb 15, 2006
4,065
Congrats on purchasing one of if not THE best car ever made!

Perhaps the easiest way is to snap a good picture of the pulley and post it here and me or one of several other people can tell you if that is a stock pulley or not.
 
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69b302

GT Owner
Mark II Lifetime
Mar 13, 2021
65
Upstate NY
Most non-OEM pulleys are in the 2.7/2.8” range. Stock is 3.25” I believe.
 
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Anderson

GT Owner
May 8, 2021
16
San Diego & FL
Measuring diameter from the lip edges I get just under 3.5” on the stock pulley.
31AB4B36-B073-4E41-88AC-3EFE63DC04B3.jpeg Aftermarket is noticeably smaller.68D0F452-30E4-47B8-9E79-4938E19930B1.jpeg
 

CmdrDCM

Member
Oct 1, 2022
16
Duluth MN
Thanks for all the help folks. It's 3.5 inches so looks to be stock. I'm thinking about upgrading to the smaller pulley.
 

Anderson

GT Owner
May 8, 2021
16
San Diego & FL
Thanks for all the help folks. It's 3.5 inches so looks to be stock. I'm thinking about upgrading to the smaller pulley.
Highly recommend it plus the tune to go with it. I got mine from Torrie @ unleashed tuning on here. 👍🏼
 

jaxgt

GT Owner
Mark IV Lifetime
Jul 12, 2006
2,734
Pulley and proper tune best bang for the buck IMHO.
It does typically start the slippery slope of mods.
Where (geographically) are you based? If west coast, might want someone like Kendall to go through your new purchase!
 

texas mongrel

GT Owner
Mark II Lifetime
May 3, 2009
1,619
Houston Texas
Pulley and tune is the cheapest horsepower you can buy. Also a DIY project if you are moderately talented, just an afternoon’s work. With hindsight, I should have quit at this mod as it maintains 100% driveability, but I had to keep on messing! Now have 682rwhp but to be honest, driveability is compromised a little, mostly due to the MAF
 
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Tomcat

GT Owner
May 23, 2013
1,136
North Carolina & Perdido Key
I did pully/tune/map/plugs/inlet support...and added a polished Accufab throttle body.
 
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jaxgt

GT Owner
Mark IV Lifetime
Jul 12, 2006
2,734
David - curious what you are referring to when you said driveablity a bit affected by MAF?
 

2112

Blue/white 06'
Mark II Lifetime
Hmm, I have a 3.8L Whipple with the Mafia and zero driveablity issues.

This is the most spectacular car I have ever been lucky enough to own.

Yes, I am a fanboy.
.
 

texas mongrel

GT Owner
Mark II Lifetime
May 3, 2009
1,619
Houston Texas
David - curious what you are referring to when you said driveablity a bit affected by MAF?
With the awesome-looking cold air intake installed, depending on side winds and other weird stuff, the car sometimes drops its idle speed or even stalls when coming to a halt. I’ve been told that it’s because of the MAF’s location. Doesn’t do it often, but irritating when it does
 

DakotaGT

GT Owner
Mark II Lifetime
Dec 9, 2012
1,600
Sioux Falls, South Dakota
With the awesome-looking cold air intake installed, depending on side winds and other weird stuff, the car sometimes drops its idle speed or even stalls when coming to a halt. I’ve been told that it’s because of the MAF’s location. Doesn’t do it often, but irritating when it does


I am familiar with this issue on these custom intake setups. I highly suggest you try this (or something similar) :


Very easy and cheap to try, and I suspect you'll be pleased.
 
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Tomcat

GT Owner
May 23, 2013
1,136
North Carolina & Perdido Key
With the awesome-looking cold air intake installed, depending on side winds and other weird stuff, the car sometimes drops its idle speed or even stalls when coming to a halt. I’ve been told that it’s because of the MAF’s location. Doesn’t do it often, but irritating when it does
I was doing research last year about cross-wind/MAF/laminar flow and I (thought I) understood it was a very uncommon but "known" anomaly (modified or stock)...experts?
 

texas mongrel

GT Owner
Mark II Lifetime
May 3, 2009
1,619
Houston Texas
I am familiar with this issue on these custom intake setups. I highly suggest you try this (or something similar) :


Very easy and cheap to try, and I suspect you'll be pleased.
Cool! I’ll give it a try, will be the cheapest fix in history if it works. Thx for the heads-up.
 
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GT101

*UK Support*
Supporting Vendor
Jan 20, 2010
348
Colchester, Essex, UK
I was doing research last year about cross-wind/MAF/laminar flow and I (thought I) understood it was a very uncommon but "known" anomaly (modified or stock)...experts?
I was advised by the Roush calibrators who worked on the GT project that it was sensitive enough to this that if you left it idling with the engine cover open and there was enough cross wind it can stall from idle.
We tried it and they were (unsurprisingly) right.
The engine cover is part of the intake system blending air from outside with air from the engine compartment. Without the cover it's drawing fresh air just from the two intake ports of the air box and if that's not even from both sides it gets upset.
 
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nota4re

GT Owner
Mark IV Lifetime
Le Mans 2010 Supporter
Feb 15, 2006
4,065
The stock GT gets it cold air directly from the large ducts on the clamshell. You will notice that the rubber "boots" on each side of the airbox will seal against the clamshell when closed. It is VERY hard to improve upon this design. Not sure what "cold air" system you have, but it is good that you like the design because in function it's quite possible to be inferior to the OEM set-up.
 

Tomcat

GT Owner
May 23, 2013
1,136
North Carolina & Perdido Key
I was advised by the Roush calibrators who worked on the GT project that it was sensitive enough to this that if you left it idling with the engine cover open and there was enough cross wind it can stall from idle.
We tried it and they were (unsurprisingly) right.
The engine cover is part of the intake system blending air from outside with air from the engine compartment. Without the cover it's drawing fresh air just from the two intake ports of the air box and if that's not even from both sides it gets upset.
I was advised that even just adding K&N air filters could manifest the cross-wind/stall situation. I experienced it twice (once the engine died and once it just stumbled) in strong (coastal) 90 degree crosswind condition at idle (with no forward velocity) at a stoplight.
 

DakotaGT

GT Owner
Mark II Lifetime
Dec 9, 2012
1,600
Sioux Falls, South Dakota
Here is my custom-made intake. I was having the same issue with wide and constant fluctuation of the MAF readings, causing erratic idle and frequent engine dying when I would let off the gas (especially when pushing the clutch in and letting off the throttle at speed). The honeycomb material worked amazingly well in my case to stabilize and streamline the airflow and instantly cured those issues. Your results may vary.




bumpdel14.JPG


honeycomb.jpg

bump13.JPG
 
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06 fgt

Well-known member
Jul 20, 2022
62
arnold mo
do you have to remove the clamshell to install x pipe and borla exhaust?