new injectors and mass air but less power?

StripedStangLX · 04-26-2001, 07:09 PM

I just recently installed 24# hr injectors in my 5.0 with a new Pro-M75mm mass air meter. I thought i may gain some power but i actually lost some. It is obviously a tuning problem but i am not sure what i should do to gain my lost power back. Can someone please lead me in the right direction? Thanks for the help.

------------------
91 LX: Green/white stripes, cam, roller rockers, underdrive pulleys, K&N, full length headers, high flow H-pipe, Flowmaster mufflers, other little engine mods, and some suspension work

93CobraR · 04-26-2001, 07:24 PM

You don't have enough motor for tose yet but thats not the problem. Do you have an adjustable fuel pressure regulator? If not get or if you do try turning down the pressure to like 34 lbs. or so.

------------------
87 GT, 4 inch cowl hood,17x9 Cobra R's/255/45's,GT-40 heads,long tubes headers,h-pipe,Flows,BBK cold air, Mass air,70mm MAF, 1.7's, 1" spacer,underdrive pulleys,Pro 5.0, King Cobra, Adj. fuel Reg., Lakewood Lift Bars,50/50's,subframes, 4.10's.
Best time 12.96
Best MPH 103.42
Best 60' 1.695

Visit my site at:
http://www.geocities.com/cobrar93_2000/MyPage.html

04-26-2001, 08:47 PM

Is your MAF calibrated for 24 #ers? I would tend to agree w/ CobraR, you need other mods to make it all work right (intake/TB/heads. Lowering your fuel pressure might help.

------------------
'90 LX 5.0; 12K original miles (no sh*&); 3.55 gears; pulleys;Edelbrock Performer Heads; BBK shorties; MSD 6AL box w/ blaster 2 coil; Motorsport E303 cam; Pro-M 75mm MAF; BBK 70mm TB; Eibach spring kit; Southside welded subs; K&N cone filter charger; Hurst shifter; fiberglass turbo hood; A/C-less; rear seat-less; cat-less; 2 chamber Flos; Corbeau racing seats (fronts);
30# injectors; 190 lb fp; FPR; TFS track heat Intake - 12.513 @ 112 mph (Pre-inj/fuelpump/FPR/intake)

Stang_ROTY · 04-26-2001, 10:15 PM

The problem might be that you have a stock computer. If you upgrade to larger injectors without reprogamming your fuel and spark curve you might be running the motor a little rich? That is what SpeedChips told me.

I'm building a project 5.0 and they told me that I'd be lucky to start my engine with 30lb. injectors, a 70mm throttle body, and a Cartech fuel system feeding a 392 stroker. Give them a call. It's worth a shot!

------------------
In progress for Spring:

93 GT less motor and tranny, 8 pt cage, chute,
Sothside Machine bars & Sub-frames, 3.73's
'69 393 stroker Edlebrock Performer heads, Performer RPM Upper & Lower Manifold..Crane Gold 1.6 Rollers..BBK 70MM TB & cats..30lb Injectors..Cartech Fuel System..

TEXSN95 · 04-27-2001, 11:52 PM

[QUOTE]Originally posted by Stang_ROTY:
[B]"""The problem might be that you have a stock computer. If you upgrade to larger injectors without reprogamming your fuel and spark curve you might be running the motor a little rich? That is what SpeedChips told me.
I'm building a project 5.0 and they told me that I'd be lucky to start my engine with 30lb. injectors, a 70mm throttle body, and a Cartech fuel system feeding a 392 stroker. Give them a call. It's worth a shot!"""

Speedchips isn't very smart. The stock EEC will learn and adjust for the new injectors/MAF to make it run right, but only if the parts are correctly calibrated. It actually does a great job of doing that. You can't even re-program the EEC...that's what custom burned chips are for. 24s are too much for what you have anyways. I agree with the previous...get an adjustable FPR and lower your fuel pressure and make sure your MAF is correctly calibrated.

------------------
Clint L.
White 95 Cobra #3637
58cc GT40X heads with mild porting, Crane 2031 cam, FRPP 65 TB, 1.7s, Cobra intake, homeade cold air, 155lph, pullies, Tokico Illuminas, C springs, GW lower control arms, Steeda CC plates, aluminum driveshaft, Steeda quadrant, MSD6A, Mac shorties, off road hpipe, 2 1/2 ultra flows w/ dumps, R hood, Euro clear corners, stock 3.08s
13.61 @ 104.7 w/ 2.22

[This message has been edited by TEXSN95 (edited 04-28-2001).]

withamc · 04-28-2001, 12:28 AM

I'm also running the 24# injectors. When I took it in to be tuned my fuel pressure regulator was set to 39 PSI (no vacuum). The tuner pulled it back to about 35 PSI and bumped the timing to 16* and I got another 35 HP. I'm about 320 at the flywheel, you're probably less than that so you need to pull yours down even further - maybe 32? Check the analyzer on this site, plug in your numbers and you'll get an idea where to set it.

------------------
86 GT, GT40P heads, Crane 2031, 1.7 RR's, Cobra intake, 65mm TB, 73mm Vortech, 24# injectors, MAC GT40P headers, 2-1/2" BBK H-pipe (w/cats), Flowmasters, 3.55s, Groundpounder subs and lower control arms, 277 RWHP.
THIS JUST IN!! All the good stuff is going in the new red 93 GT - no more rattles!

TEXSN95 · 04-28-2001, 12:35 AM

Quote:

Originally posted by withamc:
I'm also running the 24# injectors. When I took it in to be tuned my fuel pressure regulator was set to 39 PSI (no vacuum). The tuner pulled it back to about 35 PSI and bumped the timing to 16* and I got another 35 HP. I'm about 320 at the flywheel, you're probably less than that so you need to pull yours down even further - maybe 32? Check the analyzer on this site, plug in your numbers and you'll get an idea where to set it.

Wow you gained 35 hp from that?? My stock regulator is at 38 w/out vac, but I keep getting an 02 lean code, but "only" when I'm cruising at 70+mph in 5th for awhile. No other time whatsoever. And that started after I put on my homeade cold air. My stock 70mm MAF is also postless, which would further lean it out a bit. I do need an adjustable FPR, and my timing is 14. I'm weary of bumping it more when it's doing what it is right now. Did you have yours dynoed? If so then I should have a bit more than that, and I know it has more than a 104.7 with my current combo.

------------------
Clint L.
White 95 Cobra #3637
58cc GT40X heads with mild porting, Crane 2031 cam, FRPP 65 TB, 1.7s, Cobra intake, homeade cold air, 155lph, pullies, Tokico Illuminas, C springs, GW lower control arms, Steeda CC plates, aluminum driveshaft, Steeda quadrant, MSD6A, Mac shorties, off road hpipe, 2 1/2 ultra flows w/ dumps, R hood, Euro clear corners, stock 3.08s
13.61 @ 104.7 w/ 2.22

withamc · 04-28-2001, 09:48 AM

Quote:

Originally posted by TEXSN95:
Wow you gained 35 hp from that??

First run on the dyno was 243 HP, but it was running rich and the timing was set at 13*. All the guy did was pull the fuel pressure down and set the timing to 16*. After that I dynoed 277. Whoops - sorry - 34 HP.

StripedStangLX · 04-29-2001, 12:54 PM

The MAF is calibrated for 24# injectors. I have Mallory fuel rails and regulator that were on the car when i got it but i am not sure if it is adjustable or not. I haven't had any time to check it out yet. I should have looked at it closer when i had the intake off.

------------------
91 LX: Green/white stripes, cam, roller rockers, underdrive pulleys, K&N, full length headers, high flow H-pipe, Flowmaster mufflers, other little engine mods, and some suspension work

04-29-2001, 03:57 PM

I just had my intake/injectors/FPR/fuel pump installed last weekend. I heard mixed opinions and was even told by SuperChips that my car wouldn't start when mods were complete. Guess what? They were sooooo wrong. The car started just fine and it is *******' meaner than ever. The only thing we had to do was take the f/p down to 35. I chose the 30#'s because I'll be s/c soon.

------------------
'90 LX 5.0; 12K original miles (no sh*&); 3.55 gears; pulleys;Edelbrock Performer Heads; BBK shorties; MSD 6AL box w/ blaster 2 coil; Motorsport E303 cam; Pro-M 75mm MAF; BBK 70mm TB; Eibach spring kit; Southside welded subs; K&N cone filter charger; Hurst shifter; fiberglass turbo hood; A/C-less; rear seat-less; cat-less; 2 chamber Flos; Corbeau racing seats (fronts);
30# injectors; 190 lb fp; FPR; TFS track heat Intake - 12.513 @ 112 mph (Pre-inj/fuelpump/FPR/intake)

04-26-2001, 07:09 PM	#1
StripedStangLX Registered Member Join Date: Jan 2001 Location: Kintnersville, PA USA Posts: 38	new injectors and mass air but less power? I just recently installed 24# hr injectors in my 5.0 with a new Pro-M75mm mass air meter. I thought i may gain some power but i actually lost some. It is obviously a tuning problem but i am not sure what i should do to gain my lost power back. Can someone please lead me in the right direction? Thanks for the help. ------------------ 91 LX: Green/white stripes, cam, roller rockers, underdrive pulleys, K&N, full length headers, high flow H-pipe, Flowmaster mufflers, other little engine mods, and some suspension work

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04-26-2001, 07:24 PM	#2
93CobraR Registered Member Join Date: Oct 1999 Location: Cincinnati, Ohio Posts: 1,575	You don't have enough motor for tose yet but thats not the problem. Do you have an adjustable fuel pressure regulator? If not get or if you do try turning down the pressure to like 34 lbs. or so. ------------------ 87 GT, 4 inch cowl hood,17x9 Cobra R's/255/45's,GT-40 heads,long tubes headers,h-pipe,Flows,BBK cold air, Mass air,70mm MAF, 1.7's, 1" spacer,underdrive pulleys,Pro 5.0, King Cobra, Adj. fuel Reg., Lakewood Lift Bars,50/50's,subframes, 4.10's. Best time 12.96 Best MPH 103.42 Best 60' 1.695 Visit my site at: http://www.geocities.com/cobrar93_2000/MyPage.html

04-26-2001, 08:47 PM	#3
bada$$lx Guest Posts: n/a	Is your MAF calibrated for 24 #ers? I would tend to agree w/ CobraR, you need other mods to make it all work right (intake/TB/heads. Lowering your fuel pressure might help. ------------------ '90 LX 5.0; 12K original miles (no sh*&); 3.55 gears; pulleys;Edelbrock Performer Heads; BBK shorties; MSD 6AL box w/ blaster 2 coil; Motorsport E303 cam; Pro-M 75mm MAF; BBK 70mm TB; Eibach spring kit; Southside welded subs; K&N cone filter charger; Hurst shifter; fiberglass turbo hood; A/C-less; rear seat-less; cat-less; 2 chamber Flos; Corbeau racing seats (fronts); 30# injectors; 190 lb fp; FPR; TFS track heat Intake - 12.513 @ 112 mph (Pre-inj/fuelpump/FPR/intake)

04-26-2001, 10:15 PM	#4
Stang_ROTY Registered Member Join Date: Feb 2001 Location: Berkshire County - Massachusetts Posts: 735	The problem might be that you have a stock computer. If you upgrade to larger injectors without reprogamming your fuel and spark curve you might be running the motor a little rich? That is what SpeedChips told me. I'm building a project 5.0 and they told me that I'd be lucky to start my engine with 30lb. injectors, a 70mm throttle body, and a Cartech fuel system feeding a 392 stroker. Give them a call. It's worth a shot! ------------------ In progress for Spring: 93 GT less motor and tranny, 8 pt cage, chute, Sothside Machine bars & Sub-frames, 3.73's '69 393 stroker Edlebrock Performer heads, Performer RPM Upper & Lower Manifold..Crane Gold 1.6 Rollers..BBK 70MM TB & cats..30lb Injectors..Cartech Fuel System..

04-27-2001, 11:52 PM	#5
TEXSN95 Registered Member Join Date: Mar 2001 Location: college station, tx Posts: 143	[QUOTE]Originally posted by Stang_ROTY: [B]"""The problem might be that you have a stock computer. If you upgrade to larger injectors without reprogamming your fuel and spark curve you might be running the motor a little rich? That is what SpeedChips told me. I'm building a project 5.0 and they told me that I'd be lucky to start my engine with 30lb. injectors, a 70mm throttle body, and a Cartech fuel system feeding a 392 stroker. Give them a call. It's worth a shot!""" Speedchips isn't very smart. The stock EEC will learn and adjust for the new injectors/MAF to make it run right, but only if the parts are correctly calibrated. It actually does a great job of doing that. You can't even re-program the EEC...that's what custom burned chips are for. 24s are too much for what you have anyways. I agree with the previous...get an adjustable FPR and lower your fuel pressure and make sure your MAF is correctly calibrated. ------------------ Clint L. White 95 Cobra #3637 58cc GT40X heads with mild porting, Crane 2031 cam, FRPP 65 TB, 1.7s, Cobra intake, homeade cold air, 155lph, pullies, Tokico Illuminas, C springs, GW lower control arms, Steeda CC plates, aluminum driveshaft, Steeda quadrant, MSD6A, Mac shorties, off road hpipe, 2 1/2 ultra flows w/ dumps, R hood, Euro clear corners, stock 3.08s 13.61 @ 104.7 w/ 2.22 [This message has been edited by TEXSN95 (edited 04-28-2001).]

04-28-2001, 12:28 AM	#6
withamc Registered Member Join Date: Aug 2000 Location: Thousand Oaks, CA Posts: 396	I'm also running the 24# injectors. When I took it in to be tuned my fuel pressure regulator was set to 39 PSI (no vacuum). The tuner pulled it back to about 35 PSI and bumped the timing to 16* and I got another 35 HP. I'm about 320 at the flywheel, you're probably less than that so you need to pull yours down even further - maybe 32? Check the analyzer on this site, plug in your numbers and you'll get an idea where to set it. ------------------ 86 GT, GT40P heads, Crane 2031, 1.7 RR's, Cobra intake, 65mm TB, 73mm Vortech, 24# injectors, MAC GT40P headers, 2-1/2" BBK H-pipe (w/cats), Flowmasters, 3.55s, Groundpounder subs and lower control arms, 277 RWHP. THIS JUST IN!! All the good stuff is going in the new red 93 GT - no more rattles!

04-29-2001, 12:54 PM	#9
StripedStangLX Registered Member Join Date: Jan 2001 Location: Kintnersville, PA USA Posts: 38	The MAF is calibrated for 24# injectors. I have Mallory fuel rails and regulator that were on the car when i got it but i am not sure if it is adjustable or not. I haven't had any time to check it out yet. I should have looked at it closer when i had the intake off. ------------------ 91 LX: Green/white stripes, cam, roller rockers, underdrive pulleys, K&N, full length headers, high flow H-pipe, Flowmaster mufflers, other little engine mods, and some suspension work

04-29-2001, 03:57 PM	#10
bada$$lx Guest Posts: n/a	I just had my intake/injectors/FPR/fuel pump installed last weekend. I heard mixed opinions and was even told by SuperChips that my car wouldn't start when mods were complete. Guess what? They were sooooo wrong. The car started just fine and it is ******' meaner than ever. The only thing we had to do was take the f/p down to 35. I chose the 30#'s because I'll be s/c soon. ------------------ '90 LX 5.0; 12K original miles (no sh&); 3.55 gears; pulleys;Edelbrock Performer Heads; BBK shorties; MSD 6AL box w/ blaster 2 coil; Motorsport E303 cam; Pro-M 75mm MAF; BBK 70mm TB; Eibach spring kit; Southside welded subs; K&N cone filter charger; Hurst shifter; fiberglass turbo hood; A/C-less; rear seat-less; cat-less; 2 chamber Flos; Corbeau racing seats (fronts); 30# injectors; 190 lb fp; FPR; TFS track heat Intake - 12.513 @ 112 mph (Pre-inj/fuelpump/FPR/intake)