2003-04 Mach 1 Registry Owners Club - View Single Post

hamradioextra · 06-06-2004, 03:20 AM

The smaller the hole, the faster the drop. Like Canuck said, get it too small and the engine will not idle properly.

In my case, 9/32 is perfect because with the auto in gear and the A.C. on, the idle is already taxed. Turn the fan on high and the alternator will decrease your RPMs even more.

The manual trannies can probably go one size smaller, depending on the condition of your engine tune up. I tried the smaller size first but didn't like the extremely low RPM on a cold engine. After increasing the size to 9/32, it was perfect, for me.

IMHO, 9/32 is probably the optimum for most of us.

Many people on this site who weren't raised with carburated engines like I was, don't even realize that there is an RPM hang. The earlier EFI engines didn't have this problem either. This has been bugging me regarding the newer, computer controlled cars for a long time.

Glad it's finally over.

Apparently the purpose is to burn all the fuel from the system after letting up on the gas.

Like Canuck said, there is more "Burble" now after letting off on the gas pedal, primarily because the unburned fuel is now leaving small back fire sounds, hence, the Burble sound.

It now sounds like my 70s and 80s cars.

Gotta love it.

BTW, I used a piece of sheet steel for my mod. It really doesn't matter what material you use, as long as it is perfectly flat and strong. Any metal will do.

Again, I want to say, Great Piece of Info from Canuck!!

http://www.mach1registry.org/photopo...500&ppuser=140

David <><

06-06-2004, 03:20 AM	#8
hamradioextra Desert Rat Join Date: Sep 2003 Location: Southern Arizona Posts: 276	Fast Drop in RPMs The smaller the hole, the faster the drop. Like Canuck said, get it too small and the engine will not idle properly. In my case, 9/32 is perfect because with the auto in gear and the A.C. on, the idle is already taxed. Turn the fan on high and the alternator will decrease your RPMs even more. The manual trannies can probably go one size smaller, depending on the condition of your engine tune up. I tried the smaller size first but didn't like the extremely low RPM on a cold engine. After increasing the size to 9/32, it was perfect, for me. IMHO, 9/32 is probably the optimum for most of us. Many people on this site who weren't raised with carburated engines like I was, don't even realize that there is an RPM hang. The earlier EFI engines didn't have this problem either. This has been bugging me regarding the newer, computer controlled cars for a long time. Glad it's finally over. Apparently the purpose is to burn all the fuel from the system after letting up on the gas. Like Canuck said, there is more "Burble" now after letting off on the gas pedal, primarily because the unburned fuel is now leaving small back fire sounds, hence, the Burble sound. It now sounds like my 70s and 80s cars. Gotta love it. BTW, I used a piece of sheet steel for my mod. It really doesn't matter what material you use, as long as it is perfectly flat and strong. Any metal will do. Again, I want to say, Great Piece of Info from Canuck!! http://www.mach1registry.org/photopo...500&ppuser=140 David <>< __________________ David Paul <>< Current Rides: 04 Cobra Redfire 03 Sport Trac Oxf. White. Most Recent Rides: 03 Mach 1 DSG Automatic 03 Mustang DSG V6 5 Spd. 98 Explorer Sport 5 Spd. 2000 Focus ZTS 5 Spd. 98 Contour 5 Spd. The rest? Way too many to list during my 60+ years of fun loving, speed loving life. Last edited by hamradioextra; 06-06-2004 at 03:48 AM.