JMS chip owners!!! Come answer my bottom line questions.

[SlowStang2]

I am in the process of getting money together and getting one of these to unleash some hidden HP, but I have my doubts. Is the main reason for these chips to cure driveability problems? I have read previous posts and most people have ordered these chips to cure certain problems (idle surge, overheating, pinging etc) and I just want some extra power. My driveability problems arent as bad as others, so now I am thinking that a JMS chip may not be for me. Also, since my car is a 94 it is equipped with this terrible computer and I was wondering that if I did, in fact, get one of these and experienced some improvement in power, is it going to temporary? Is my great computer going to learn from the changes and return to its normal routine? Also, one person, only one person has said he has gotten a full 1/2 second off his quarter time from one of these, but what about everyone else? I need some real track times here. I am picky about what I buy. I do not like spending money on mods unless I will be able to "feel" the difference. Thanx.

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94' Stang GT Convertible --Cobra upper&lower, GT-40Y Turbo Swirl aluminum heads, Mac cold air w/K&N, BBK equal length shorties, BBK offroad H-pipe, American Thunder cat-back, BBK T/B 65mm, 24lb injectors, Pro-77mm MAM, pulleys, aluminum driveshaft, 3.55s, Steeda Tri-Ax shifter, adjustable fuel regulator, Steeda strut tower and subframes 14.0@102 MPH on G-tech;?MPH at track. I know, I know I am working on it. Now I have FRPP 1.7 RRs and new lifters, yes the ticking is gone!!!

[302 LX Eric]

I purchased one a few months ago but have not been able to dnyo it or take it to the track to see results.

What I can tell you is that the chip did fix my warm engine/high idle issue. Other than that, "seat-of-the-pants" feel is very difficult to distinguish when you're only talking 15 horse - maybe.

As the for the chips themselves, basically all they do is lean out the fuel curve and bump timing. They come with three programs that you can change to see how your car reacts. (2% rich, 2% lean, and 4% lean)

I think that the chips can be very good for "fine-tuning" your car, but re-burns maybe necessary to get it all correct.

Since purchasing and installing the chip, I have switched to an aluminum flywheel, cobra clutch and Tremec 3550 - so when I do get to the track (probably next year) it will be difficult to deduce what part had what effect.

Take care,
E

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1991 5.0 LX Coupe - 38,000 miles

13.17 @ 106.14 mph w/ 2.138 60'

I was having some serious driveability problems after my intake/fuel system additions. The JMS chip cured my idle problems. After these last mods I dropped almost .4 on the 1/4 and gained about 5 mph. I can't tell how much of that was the chip itself, but I know w/out it, I would've ran slower than I had before those mods.

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'90 LX 5.0;12K original miles;FMS 3.55 gears; March pulleys;Edelbrock Performer Heads;BBK 1 5/8" equal length shorties;MSD 6AL ignition w/ blaster 2 coil;FMS E303 cam;Pro-M 75mm MAF;BBK 70mm TB; Eibach drag-launch spring kit;Southside weld-on subs;9" K&N cone filter charger;Hurst shifter;Cervini 3" turbo hood;A/C delete;gutted cats;2 chamber Flomasters;Corbeau racing seats;FMS 30# injectors;JMS custom chip;Holley 190lb fp;TFS track heat intake (12.299 @ 113mph w/ a 1.78 60')
....soon to be b

[SlowStang2]

Hell, 2 tenths is enough for me. Infact, that would be the minimal. Is the installation the same as you would install a hypertech chip? Ya know, is it plug and go?

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94' Stang GT Convertible --Cobra upper&lower, GT-40Y Turbo Swirl aluminum heads, Mac cold air w/K&N, BBK equal length shorties, BBK offroad H-pipe, American Thunder cat-back, BBK T/B 65mm, 24lb injectors, Pro-77mm MAM, pulleys, aluminum driveshaft, 3.55s, Steeda Tri-Ax shifter, adjustable fuel regulator, Steeda strut tower and subframes 14.0@102 MPH on G-tech;?MPH at track. I know, I know I am working on it. Now I have FRPP 1.7 RRs and new lifters, yes the ticking is gone!!!

The install was probably the easiest mod I've ever done to the car -pop it in and go, basically. Hey Eric......quick question for you - I know they come w/ the 3 programs, but how do you change from one to the other? Is it just a matter of unplugging and plugging each of the wires hanging off the side?

[Skyman]

Bada$$lx- What did you change to gain 5mph in the 1/4? And what did you have before.

Thats a huge increase!

Skyler

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-1989 Saleen Mustang #406-
TFS TW Heads, E-303, Edelbrock intake, 70mm TB, 73mm MAF, 24lb injectors, 1 5/8 shorties, Off Road H, 3 Chamber flows, Jaz Race seats, Back seat removed, sub-frames, Roll Cage, and a 80 shot of N20.
12.54@107.4 Motor
332RWHP, 350rwtq

[Matt Harwood]

If your car is already running well, a chip probably won't give you big gains. I went through three chips and two MAF meters on FrankenRanger (see sig.) before I got it dyno tuned. My goal was to cure driveability problems with the Kenne-Bell blower, but with the chip, we were able to find an additional 96 horsepower in the truck. But without the dyno, we would not have been able to do this. My JMS chip (which I tossed) ran the truck OK, but didn't make any power I could feel.

I'm of the opinion that a chip is wasted money until you have substantial modifications that start to affect driveabililty. And at that point, you should get it tuned properly on a dyno, since it's basically shooting in the dark to try to program a chip via mail-order. For your money, there are better upgrades that will make more power.

Hope this helps.

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Matt Harwood
Harwood Performance Engineering
Cleveland, OH

1993 LX coupe: built 342, GT-40X heads, ported Cobra intake, JBA headers, 3.55s, etc., etc., etc.

FOR SALE: 1997 Ranger Splash Supercab: 1995 Cobra 5.0L, 8 PSI Kenne-Bell supercharger, Tremec 3550, 75mm Pro-M, 3.55s, fully functional PS, ABS, ice cold A/C and emissions legal.

See it all at:
www.harwoodperformance.bizland.com

[moponys]

Bada$$,

There should be a piece of paper that came with the chip that tells you which dip switches to flip to move to different programs on your chip. It's easy to do (example all switches down is test mode, 1st switch up is program 1, etc.)

slowstang,

Oh yeah, along with running better, your car will feel a lot more responsive when you get on the gas. I don't have any before and after times or dyno numbers bit it definately feels faster but then again I could wash my car and change the windshield wipers and it would feel faster to me.

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94 GT convert:TFS twisted wedge heads, TFS street intake, Lunati cam .500/.510 218/226, BBK FPR, BBK shorties, BBK 70mm tb, Pro-m 75mm, ASP pulleys, FMS 3:73, Transgo shiftkit,Flowmasters, Bassani x-pipe, K&N FIPK, FMS 1.6 roller rockers, 9mm wires,24lbs injectors,
190lph fuel pump, MSD cap and rotor, 18" wheels w/street tires, JMS custom chip, Trickflow phenolic spacer. ETs soon to come...

[SlowStang2]

Damn, well I gotta tell ya, this isnt music to my ears. I sent a letter to JMS to get some hands down feedback as to if I am diggin for nothing right now. Its just that with all my mods and this great computer of mine, I really believe I should be running faster. And if this chip can improve on any restraint my computer is putting on my mods, then I gotta try. But $300 is a little too much to just try.

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94' Stang GT Convertible --Cobra upper&lower, GT-40Y Turbo Swirl aluminum heads, Mac cold air w/K&N, BBK equal length shorties, BBK offroad H-pipe, American Thunder cat-back, BBK T/B 65mm, 24lb injectors, Pro-77mm MAM, pulleys, aluminum driveshaft, 3.55s, Steeda Tri-Ax shifter, adjustable fuel regulator, Steeda strut tower and subframes 14.0@102 MPH on G-tech;?MPH at track. I know, I know I am working on it. Now I have FRPP 1.7 RRs and new lifters, yes the ticking is gone!!!

Thanks moponys. Skyler...it obviously wasn't the chip alone that got me the 5 mph - I chipped the car after swapping out my stock intake, MAF, TB, increasing injector size/fuel pump.

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'90 LX 5.0;12K original miles;FMS 3.55 gears; March pulleys;Edelbrock Performer Heads;BBK 1 5/8" equal length shorties;MSD 6AL ignition w/ blaster 2 coil;FMS E303 cam;Pro-M 75mm MAF;BBK 70mm TB; Eibach drag-launch spring kit;Southside weld-on subs;9" K&N cone filter charger;Hurst shifter;Cervini 3" turbo hood;A/C delete;gutted cats;2 chamber Flomasters;Corbeau racing seats;FMS 30# injectors;JMS custom chip;Holley 190lb fp;TFS track heat intake (12.299 @ 113mph w/ a 1.78 60')
....soon to be b

[302 LX Eric]

A complete dyno tune with wide-band O2 is probably the best way to go.

As for changing programs, I have a "dip switch" that I routed into the glove box where I can change b/t programs. As stated above, my chip came with program parameters that are activated by the different positions of the switches.

I am very curious as to what type of gains I will see in the 1/4. Throttle response does seem to be better - but again this can be difficult to tell. I will definately post back about the results of my alum. fly and JMS chip combo. I want 107 mph and 12.9 out of my stang on drag radials, that would make me happy!

E

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1991 5.0 LX Coupe - 38,000 miles

13.17 @ 106.14 mph w/ 2.138 60'

[Rebel79]

I purchased my JMS chip a while back. At the time I saw a minimal increase in power, yet I could not take the car over 5k due to the agressive timing. After working out my fuel system and ignition systems I have come to the following conclusions:

Pros

• The car runs like a raped ape.
• Runs the car cooler (turns fan on at 195°)

Cons

• Have less throttle response
• Less low end torque
• Idle surges
• I no longer have my idle that sounds like i have a huge cam.

I will be dumping mh JMS chip for a PMS or equivelent when I have the cash.


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1994 Mustang Cobra
308ci, Vortech S-trim 11#, ported GT-40 heads, E-303 cam, FMS 1 5/8 headers, BBK Offroad H-pipe, 2-chamber flows, and several other goodies.
Rebel Racing. Home of Bay Area Mustangs

[SlowStang2]

Wow, Rebel thats enough Cons to keep me away. Afterall, our years are the same. What about a Diablo chip? Latest 5.0 mag. says they picked up a 59hp increase. Of course, its a different setup, but still there may be something there. Yea the dynos were different, but still again, theres gotta be something. And if I take my car to Rieth Motorsports, I believe they custom burn diablos. What do u think?

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94' Stang GT Convertible --Cobra upper&lower, GT-40Y Turbo Swirl aluminum heads, Mac cold air w/K&N, BBK equal length shorties, BBK offroad H-pipe, American Thunder cat-back, BBK T/B 65mm, 24lb injectors, Pro-77mm MAM, pulleys, aluminum driveshaft, 3.55s, Steeda Tri-Ax shifter, adjustable fuel regulator, Steeda strut tower and subframes, 1.7 RRs 13.8@100 MPH It's about time.

[todd95GT]

I am going to Rieth Motorsports this Saturday-Steve is installing the 4.10's in my '95. I'll ask him about the chip for you as I will be looking for a custom burn when I install my upper half (cam, heads, intake, etc.). I'll post his answer or e-mail me privately. My address is in my profile.

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Todd
1995 GT/T-5
Pulleys; 65 mm TB; Flowmaster cat-back; Mac off road H-pipe; FMS aluminum driveshaft; short-throw shifter; HD clutch; Cobra R's; Cobra front and wing

I'm such a dumb a$$.......I didn't remember about the JMS chip having multiple programs, so when you guys started talking about it, I thought I'd try the different ones out. I really like my JMS chip, don't get me wrong.....it's helped my car out, driveability wise, tremendously. But, since my last few mods, heads, intake, fuel system etc, I've felt that the car wasn't giving it's ALL. So, I figured I'd jump from the 1st program straight to the 3rd. WOW, no B$, the car feels extremely reponsive and I broke traction and went sideways mid 3rd and beginning of 4th. Can someone w/ the JMS chip tell me the difference between the 3 programs? Is the 3rd program supposed to be "radical" and is it safe to run 24/7?

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'90 LX 5.0;12K original miles;FMS 3.55 gears; March pulleys;Edelbrock Performer Heads;BBK 1 5/8" equal length shorties;MSD 6AL ignition w/ blaster 2 coil;FMS E303 cam;Pro-M 75mm MAF;BBK 70mm TB; Eibach drag-launch spring kit;Southside weld-on subs;9" K&N cone filter charger;Hurst shifter;Cervini 3" turbo hood;A/C delete;gutted cats;2 chamber Flomasters;Corbeau racing seats;FMS 30# injectors;JMS custom chip;Holley 190lb fp;TFS track heat intake (12.299 @ 113mph w/ a 1.78 60')
....soon to be b

[302 LX Eric]

bada$$lx

Here are how my programs are laid out:

#1 - 800 rpm idle, 7000 rpm rev limit, touch more accel pump, set total timing to 32 degrees, WOT fuel set 2% LEANER than stock, turned off thermactor, modified to fix bad idle (hot and cold).

#2 - same as #1, only WOT is 4% LEANER than stock

#3 - same as #1, only WOT is 2% RICHER than stock

- Program #1 is active when dip switch is on;
- Program #2 is active when dip switch 3 is on; and
- Program #3 is active when dip switch 1 and 3 are on

You may want to call JMS to see what programs you have for each set.

Take care, E

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1991 5.0 LX Coupe - 38,000 miles

13.17 @ 106.14 mph w/ 2.138 60'

Eric, I lost my spec sheet from JMS and I called Chris and he said because I got mine prior to their shop being wrecked by the tornado, he doesn't have my info anymore....oh well. He said to run it trying each of the 3 settings. Program #3 seemed to be just right, do you think I should try #2? I'm pretty sure my #2 is lean and #3 is rich.....if I remember seeing it correctly. Thanks.

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'90 LX 5.0;12K original miles;FMS 3.55 gears; March pulleys;Edelbrock Performer Heads;BBK 1 5/8" equal length shorties;MSD 6AL ignition w/ blaster 2 coil;FMS E303 cam;Pro-M 75mm MAF;BBK 70mm TB; Eibach drag-launch spring kit;Southside weld-on subs;9" K&N cone filter charger;Hurst shifter;Cervini 3" turbo hood;A/C delete;gutted cats;2 chamber Flomasters;Corbeau racing seats;FMS 30# injectors;JMS custom chip;Holley 190lb fp;TFS track heat intake (12.299 @ 113mph w/ a 1.78 60')
....soon to be b

[302 LX Eric]

You might as well give it a try and see what happens. Although, looking at your combo and ET/mph, your Stang is running VERY well - so maybe just leave it where it is?

E

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1991 5.0 LX Coupe - 38,000 miles

13.17 @ 106.14 mph w/ 2.138 60'