Can Someone Please Help 1989 Mustang LX

[stevesLX]

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?

And finally if the car is at idle the lights are dim but if you give it gas they get real bright. If your driving its fine but when you let off the gas all the lights go dim. Would that be alternater problems to small or just weak?

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.

I apologize for sounding stupid but this is my first stang and just need a little education.

So can someone please answer my questions?

 

[ryan218]

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?

And finally if the car is at idle the lights are dim but if you give it gas they get real bright. If your driving its fine but when you let off the gas all the lights go dim. Would that be alternater problems to small or just weak?

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.

I apologize for sounding stupid but this is my first stang and just need a little education.

So can someone please answer my questions?

at 70 MPH in 5th gear the 86 of ours is at 2,000rpm and its got 4:10's as well

 

[RsStanG1987]

at 70 MPH in 5th gear the 86 of ours is at 2,000rpm and its got 4:10's as well

Dude WTF what help did that offrer?

 

[RsStanG1987]

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?

And finally if the car is at idle the lights are dim but if you give it gas they get real bright. If your driving its fine but when you let off the gas all the lights go dim. Would that be alternater problems to small or just weak?

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.

I apologize for sounding stupid but this is my first stang and just need a little education.

So can someone please answer my questions?

Chances are its got a VAc leak. Your injectors are 24lbs not 25 and the TB would be 75 not 77. The lights are just dim like that because of the weak ass alt., With 4:10's you should be expectiong 10-20mpg on the highway. You most likely want a mass air sensor calibrated to you injectors and Throttle body.