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Engine Successful first start - timing question

  • Thread starter Thread starter Justin87
  • Start date Start date Jun 21, 2021

Justin87

5 Year Member
Aug 7, 2017
158
45
48
Jun 21, 2021
#1
  • Jun 21, 2021
  • #1
Hello all!

First off, I just wanted to thank all of you for answering my questions about the build and initial start up of my 90 GT. After a little trouble shooting, I successfully got her to start and make some noise!

I do have 2 questions for ya’ll to keep things moving in the right direction.
  1. Does anybody know what the timing should be with an X303 cam? Is their even such a number? Or is it a case-by-case kinda thing.
  2. In order to keep the car running I need to keep my foot at the accelerator pedal a little bit. Some of that is probably the timing, but also my throttle cable or throttle screw probably needs to be adjusted. Can I adjust the throttle screw at this point?

    (I ask because normally with a stock motor this would not be recommended with it comes to idle issue)

    A video of the car running is below. Still plenty to things to button up, exhaust hangers rattling and still need to top off the transmission with fluid and bleed to cooling system, but she’s alive!
View: https://youtu.be/_eqNup2I0tk
 

Steel1

Mustang Master
Aug 18, 2017
1,419
639
143
Connecticut
Jun 21, 2021
#2
  • Jun 21, 2021
  • #2
Some engines like a little more timing some a little less, factory was 10* but most of these cars seem to perform better
between 12* and 14* (this is all spout removed )
I would pull the spot and set it for 12* , spout back in and see how it likes it.
Once you get the timing set, which will probably help the car idle, I would do a base idle reset before messing with the idle stop.
She fired up though so that's a win !
 
Reactions: Justin87

Justin87

5 Year Member
Aug 7, 2017
158
45
48
Jun 21, 2021
#3
  • Jun 21, 2021
  • #3
Steel1 said:
Some engines like a little more timing some a little less, factory was 10* but most of these cars seem to perform better
between 12* and 14* (this is all spout removed )
I would pull the spot and set it for 12* , spout back in and see how it likes it.
Once you get the timing set, which will probably help the car idle, I would do a base idle reset before messing with the idle stop.
She fired up though so that's a win !
Click to expand...
That answers another of my question if a full base idle reset needs to be done, so thank you for that!

and yeah once o figured out what TDC was on the compression stroke (I was 180 off at first) and I gave her a little throttle she fired right up!

She’s running straight off the H-pipe now. Sounds mean as hell, but probably gotta put something on there before the first drive
 
Reactions: General karthief

Wayne Waldrep

Before I post a pic, do you have one of yours?
20+ Year Stangneter
Apr 14, 2003
1,338
659
143
Cuba, AL
Jun 23, 2021
#4
  • Jun 23, 2021
  • #4
Just in case ya need it....

Base Idle Reset

I'd like to post this for all the newer mustang owners and the others like me that never took the base idle reset seriously. I've had multiple engines and various setups but never once done the base idle reset. I just replaced the lifters in my car after having one collapse. I thought the...
www.stangnet.com
 
Reactions: Justin87

Justin87

5 Year Member
Aug 7, 2017
158
45
48
Jun 23, 2021
#5
  • Jun 23, 2021
  • #5
Wayne Waldrep said:
Just in case ya need it....

Base Idle Reset

I'd like to post this for all the newer mustang owners and the others like me that never took the base idle reset seriously. I've had multiple engines and various setups but never once done the base idle reset. I just replaced the lifters in my car after having one collapse. I thought the...
www.stangnet.com
Click to expand...
I definitely will need this for the weekend when I’ll work on the car more!

thanks!
 
Reactions: Wayne Waldrep
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