Update On Issues - Driveability and Detonation

SleeperGT · 05-04-2003, 06:23 PM

Well my long saga has finally come to an end, with my car running great, not quite as fast but running slightly faster than stock Vortech. After having the stock Vortech S-Trim installed my next upgrade was a Diablo Custom Chip, Anderson PowerPipe, and 90 mm MAS. The shop wanted me to go with 42 pound injectors but I balked at the extra money so they said they should be able to make it work with my 30 pounders. So I went with it. After the install I had serious detonation issues and some mild driveability issues, under moderate excellerations my little pony bucked like a wild bronco, under WOT or very light throttle things were OK. The car felt much faster and the track proved it out. A couple gallons of race fuel prevented the detonation. Car ran at 12.6 @ 111 mph as a best. However after about 15 runs on several trips to the track, I could never come close to that one run, as I had a few 12.7's in the 110 mph range and the car really seemed to settle into the 12.8, 109 range. The stock Vortech install with stock MAS ran 105 to 106 mph @ about 13.0 range. It turns out the 30 pound injectors couldn't push enough fuel for the 30 pound injectors, so back went in the stock MAS and a chip burn to match it. Car runs great, zero detonation, and driveability is great. Car now runs right in the middle of the stock Vortech install and the 90 mm MAS upgrade. Just back from the track the the car runs 13.0 in the 108 range. For everyone's fyi my 60 times stink, 2.0 all night long. Once I get a little more money I am going to go with the 42 pound injectors and 90 mm MAS and another chip burn. Any input on this story is alway appreciated.

Stang_Crazy · 05-04-2003, 06:33 PM

Glad to hear it's running right. Hearing detonation is the worst sound in the world. I always get out of it and re-tune the car to prevent it detonating. Are you still using the FMU? If you are, junk it. With the addition of 42's, you shouldn't need the FMU anymore. It's just a band-aid for the fuel system.

How many psi are you seeing? Get those 60' times down and you'll be loving your car!

Happiness is being blown!

Dan

SleeperGT · 05-06-2003, 02:47 PM

Thanks for the input Stang_Crazy. I have to admit, what is an FMU? Fuel Management Unit (bad guess on my part)? Is it part of the computer? I've got a Diablo chip, is that the FMU? Sorry for the stupid questions.

Stang_Crazy · 05-06-2003, 07:23 PM

The FMU is the Fuel Management Unit. Here's a link to Vortech's website. They can explain the FMU alot better than I could.

http://www.vortechsuperchargers.com/tech/fmu_sfmu.html

Dan

SleeperGT · 05-06-2003, 09:37 PM

Very helpful Crazy. Now my big question, did my Vortech come with an FMU? Looking over the parts inventory from my install, I don't see it listed. Is this something I should have installed with my current setup (stock MAS, 30 lb injectors, Anderson PowerPipe, Vortech fuel pump upgrade) or if I want to go with a 90 mm MAS?

Stang_Crazy · 05-07-2003, 06:56 PM

I don't know what all is included in the S-trim kit but I'd assume it comes with a FMU.

The 30#ers flow enough that you don't need the FMU. The custom chip also helps with the timing and fuel curves. If you move up to a 90mm MAF, make sure you ger it calibrated for the 30# injectors.

Dan

05-04-2003, 06:23 PM	#1
SleeperGT Registered Member Join Date: Sep 2002 Location: Ponte Vedra Beach, FL Posts: 122	Update On Issues - Driveability and Detonation Well my long saga has finally come to an end, with my car running great, not quite as fast but running slightly faster than stock Vortech. After having the stock Vortech S-Trim installed my next upgrade was a Diablo Custom Chip, Anderson PowerPipe, and 90 mm MAS. The shop wanted me to go with 42 pound injectors but I balked at the extra money so they said they should be able to make it work with my 30 pounders. So I went with it. After the install I had serious detonation issues and some mild driveability issues, under moderate excellerations my little pony bucked like a wild bronco, under WOT or very light throttle things were OK. The car felt much faster and the track proved it out. A couple gallons of race fuel prevented the detonation. Car ran at 12.6 @ 111 mph as a best. However after about 15 runs on several trips to the track, I could never come close to that one run, as I had a few 12.7's in the 110 mph range and the car really seemed to settle into the 12.8, 109 range. The stock Vortech install with stock MAS ran 105 to 106 mph @ about 13.0 range. It turns out the 30 pound injectors couldn't push enough fuel for the 30 pound injectors, so back went in the stock MAS and a chip burn to match it. Car runs great, zero detonation, and driveability is great. Car now runs right in the middle of the stock Vortech install and the 90 mm MAS upgrade. Just back from the track the the car runs 13.0 in the 108 range. For everyone's fyi my 60 times stink, 2.0 all night long. Once I get a little more money I am going to go with the 42 pound injectors and 90 mm MAS and another chip burn. Any input on this story is alway appreciated. __________________ '00 GT 5-spd Vortech S-Trim 3.1" Pulley Paxton Air-to-Air Aftercooler 90 mm MAS 42 lb injectors Cobra Fuel Pump 70 mm AccuFab Throttlebody C & L Intake Plenum 2 1/2" X-pipes Anderson PowerPipe MagnaFlow Mufflers Diablo Custom Chip 3.73's Steeda Lower Control Arms 358 rwhp (Mustang Dyno) New Track Times Coming Soon

05-04-2003, 06:33 PM	#2
Stang_Crazy It's never clean enough! Join Date: Jan 1999 Location: Shaler, PA Posts: 1,542	Glad to hear it's running right. Hearing detonation is the worst sound in the world. I always get out of it and re-tune the car to prevent it detonating. Are you still using the FMU? If you are, junk it. With the addition of 42's, you shouldn't need the FMU anymore. It's just a band-aid for the fuel system. How many psi are you seeing? Get those 60' times down and you'll be loving your car! Happiness is being blown! Dan __________________ ~Dan 2001 SVT Lightning 89' GT : Taking up garage space and waiting for a buyer... Rice Hater's Club - Member #11

05-06-2003, 02:47 PM	#3
SleeperGT Registered Member Join Date: Sep 2002 Location: Ponte Vedra Beach, FL Posts: 122	Thanks for the input Stang_Crazy. I have to admit, what is an FMU? Fuel Management Unit (bad guess on my part)? Is it part of the computer? I've got a Diablo chip, is that the FMU? Sorry for the stupid questions. __________________ '00 GT 5-spd Vortech S-Trim 3.1" Pulley Paxton Air-to-Air Aftercooler 90 mm MAS 42 lb injectors Cobra Fuel Pump 70 mm AccuFab Throttlebody C & L Intake Plenum 2 1/2" X-pipes Anderson PowerPipe MagnaFlow Mufflers Diablo Custom Chip 3.73's Steeda Lower Control Arms 358 rwhp (Mustang Dyno) New Track Times Coming Soon

05-06-2003, 07:23 PM	#4
Stang_Crazy It's never clean enough! Join Date: Jan 1999 Location: Shaler, PA Posts: 1,542	The FMU is the Fuel Management Unit. Here's a link to Vortech's website. They can explain the FMU alot better than I could. http://www.vortechsuperchargers.com/tech/fmu_sfmu.html Dan __________________ ~Dan 2001 SVT Lightning 89' GT : Taking up garage space and waiting for a buyer... Rice Hater's Club - Member #11

05-06-2003, 09:37 PM	#5
SleeperGT Registered Member Join Date: Sep 2002 Location: Ponte Vedra Beach, FL Posts: 122	Very helpful Crazy. Now my big question, did my Vortech come with an FMU? Looking over the parts inventory from my install, I don't see it listed. Is this something I should have installed with my current setup (stock MAS, 30 lb injectors, Anderson PowerPipe, Vortech fuel pump upgrade) or if I want to go with a 90 mm MAS? __________________ '00 GT 5-spd Vortech S-Trim 3.1" Pulley Paxton Air-to-Air Aftercooler 90 mm MAS 42 lb injectors Cobra Fuel Pump 70 mm AccuFab Throttlebody C & L Intake Plenum 2 1/2" X-pipes Anderson PowerPipe MagnaFlow Mufflers Diablo Custom Chip 3.73's Steeda Lower Control Arms 358 rwhp (Mustang Dyno) New Track Times Coming Soon

05-07-2003, 06:56 PM	#6
Stang_Crazy It's never clean enough! Join Date: Jan 1999 Location: Shaler, PA Posts: 1,542	I don't know what all is included in the S-trim kit but I'd assume it comes with a FMU. The 30#ers flow enough that you don't need the FMU. The custom chip also helps with the timing and fuel curves. If you move up to a 90mm MAF, make sure you ger it calibrated for the 30# injectors. Dan __________________ ~Dan 2001 SVT Lightning 89' GT : Taking up garage space and waiting for a buyer... Rice Hater's Club - Member #11