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Need help with 1989 LX

  • Thread starter Thread starter stevesLX
  • Start date Start date Nov 12, 2006

stevesLX

Member
Nov 12, 2006
373
0
16
cincinnati
Nov 12, 2006
#1
  • Nov 12, 2006
  • #1
I purchased a 89 LX the engine mods are as follows: 302 bored 30 over,port and polished heads,303 motorsport cam, I beleive its a 77mm throttle body, different pullys, 65CFM mass airflow sensor, 25LB injectors ,World class T-5 Tranny, aluminum driveshaft, 410 positrac, motorsport clutch and pressure plate and headers. She wants to idle a little rough and ecspecially if its below 40 degrees she's hard to keep started until she warms up.

I had one person tell me I need to change the mass air flow sensor out for a different one. If thats true can someone tell me what size as far as CFM goes?


Also I have heard so many different stories on how driving this car on the expressway with that engine and a 410 gear is going to eat me alive on gas. I've been told that in 5th gear I will be taching around 3000-3500 RPMs and it will eat me alive. But then other people tell me that they have somewhat similar set ups and they tac around 2300 in 5th gear at 65MPH and get around 20-23 MPG. So is there anyone out there that knows what is fact or fiction?


I know I have a 2004 F150 new body style with a 4.6L tahat absolutely stinks on gas mileage. I average about 18 hwy and 15 city. Its a guzzler.

So can someone please answer my questions?
 
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