new gears, springs, shocks, and mass air and car runs slower

[nyr923]

i installed a 73mm mass air, eibach drag launch springs, competition engineering drag shocks and 3.73 gears in place of the 3.55s i was running. i went to the track a week ago and went from running 13.9 at 98 mph to 14.9 at 92 mph. i checked the plugs and they were all ok, also checked the compression and got between 115 and 120 psi for each cylinder. any ideas what could cause this.

thanks

 

[rwood126]

Are you still shifting at the same RPM'S? After I installed a 3.73 in mine ..it ran slower. Then someone told me that I have to change my shifting points.

After finding where I need to shift.....it ran much quicker

 

[f8tlfiveo]

if you dont have an intake or heads on the car that mass air meter is prob making little to no difference. bigger is not always better.
it might even lower your hp.
Posted via Mobile Device

 

[strtrcr50]

With all the suspension mods you listed, what kind of tires are you running on the rear? What you now have will hit the tires hard and if they won't hook up, it will unload the suspension.

 

[67coupe]

What were the 60ft times for the two runs?

Losing 6 mph is alot.

I would suspect something with the new mass air. Is it "matched" to your injectors?

Maybe you could try installing the stock mass air and make another pass at the track?

 

[strtrcr50]

That too. C&L is pretty hit or miss.

 

[nyr923]

With all the suspension mods you listed, what kind of tires are you running on the rear? What you now have will hit the tires hard and if they won't hook up, it will unload the suspension.

im running 275/50/15 mt et street radials

 

[nyr923]

What were the 60ft times for the two runs?

Losing 6 mph is alot.

I would suspect something with the new mass air. Is it "matched" to your injectors?

Maybe you could try installing the stock mass air and make another pass at the track?

last pass last season vs most recent pass

-- before -- after
60' -- 1.965 -- 2.040
330' -- 5.713 -- 6.011
1/8 -- 8.872 -- 9.523
mph -- 8.04 -- 71.35
1000' -- 11.632 -- 12.476
1/4 -- 13.969 -- 14.945
mph -- 96.63 -- 91.84

the mass air has a 19lb tube in it and as far as i know i have stock injectors.

ill try putting the stock mass air back in next time i go to the track, hopefully next friday.

 

[67coupe]

Just noticed you have a cold air kit. Some meters don't like cold air kits. Might try clocking the C&L (rotating to different parts of the air stream) and see if it picks up any.

 

[Turd Tops]

Just noticed you have a cold air kit. Some meters don't like cold air kits. Might try clocking the C&L (rotating to different parts of the air stream) and see if it picks up any.

It did'nt click untill i saw your post. I used a C&L with the march ram air and they did'nt get along to well. I had a friend tune it and it ran much better after that. I'm no longer a fan of C&L. I know he's not running ram air but only a cold air kit but it might mean something..

 

[67coupe]

C&L's work best with the factory air box. Some have been able to "clock" the meter when using cold air kits.

Pro-M actually has a C designation for meters calibrated for use with cold air kits.

In fact, I have the old moroso cold air, I installed a 70mm ford meter (junk yard) a few months ago. I had to clock it a couple of times to find the "sweet" spot.

 

[Strype]

My car hardly ran with the cold air kit and C&L... I banged my head for weeks until someone told me to put the stock filter back on..