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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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Should I Run 70mm Throttle Body?

  • Thread starter Thread starter dz01
  • Start date Start date Jul 7, 2014

dz01

Member
Mar 31, 2005
285
10
19
Massachusetts
Jul 7, 2014
#1
  • Jul 7, 2014
  • #1
Recently bought my 93 hatch with some mods installed and a bunch of other parts that came with the car but not installed.

From what I can see:

- Cold air intake
- BBK headers
- Ignition
- Injectors (orange- not sure what size they are, but I'm pretty sure stock are red)
- Underdrive pulleys (took these off)

I also got a Trickflow intake new in the box and 70mm BBK TB. I've been working through the surging idle checklist, but still can't seem to find the issue. My idle hangs especially when the motor is warm. Eventually comes back down to 800-900, but takes a minute or so.

A friend of mine keeps pointing to the throttle body being the problem. I'm trying to figure out if it's worth running the 70mm on my car. Seems like this would be overkill on what's essentially a stock motor.

So my questions are-
-can I run a 70mm TB on my motor based on mods (probably won't put the new intake on anytime soon)?
-should I run the 70mm TB?
-what size are "orange" injectors?
 

coupeownerBE

Active Member
Aug 20, 2005
110
2
29
russellivlle,ar
Jul 7, 2014
#2
  • Jul 7, 2014
  • #2
pretty sure orange are 19lb.. I have 24lb and there a light blue almost gray. you can run the TB but really if the rest of the motor is stock I would keep saving parts until the time is right.. work on your idle for now. then when you got all your stuff you can throw all that on.
 

Mick Bellar

New Member
Jun 20, 2014
5
0
1
Jul 8, 2014
#3
  • Jul 8, 2014
  • #3
A lot of guys put stuff on and remove stuff without concern for the computer control, I always caution people because even some slight mods can turn an awesome 5.0 into a doorstop. I have a BBK 70mm with orange injectors and it runs very well, but the car was tuned and the chip was set up by reputable dyno shop. Good Luck with it.
 

dz01

Member
Mar 31, 2005
285
10
19
Massachusetts
Jul 9, 2014
#4
  • Jul 9, 2014
  • #4
Thanks guys. I wonder if running 19lb injectors with a stock MAC is causing my idle problem. Otherwise, car seems to run great.
 

dz01

Member
Mar 31, 2005
285
10
19
Massachusetts
Jul 9, 2014
#5
  • Jul 9, 2014
  • #5
Update- I assumed the extra set of injectors I got with my car were stock (they are red), but after some research, maybe the orange 19lbs are stock and the red 30lbs go with the trick flow intake and 70mm TB?
 

smkshw

5 Year Member
Feb 12, 2010
1,095
235
94
Jul 9, 2014
#6
  • Jul 9, 2014
  • #6
you wont need the 30s unless you get heads and cam..
 

dz01

Member
Mar 31, 2005
285
10
19
Massachusetts
Jul 12, 2014
#7
  • Jul 12, 2014
  • #7
Mick Bellar said:
A lot of guys put stuff on and remove stuff without concern for the computer control, I always caution people because even some slight mods can turn an awesome 5.0 into a doorstop. I have a BBK 70mm with orange injectors and it runs very well, but the car was tuned and the chip was set up by reputable dyno shop. Good Luck with it.
Click to expand...

Thanks so if I replace my TB with the 70 mm and my MAF with the one that matches, I'll have to get the computer tweaked?
 

7991LXnSHO

wanna catch the space herp
10 Year Member
Sep 1, 2010
7,387
2,745
194
Kearney, NE
Jul 12, 2014
#8
  • Jul 12, 2014
  • #8
No computer twerking is needed for a 70 mm tb. It is a little big for stock but it will not hurt anything.
 
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