vortechcharger

First off, just want to say great forum/members and really good info!

So here's my issue(s). I have purchased a 1987 Mustang GT for my 17yr old son. I am not a mechanic by any means but we have decided to tackle this car as a father and son project. Car came with Saleen intake, 75mm throttle body, 30lb injectors, Paxton SN 2000 supercharger and MAF calibrated for 30lb injectors and headers. I have removed the supercharger and put on a normal aftermarket air intake (SR Intake).

Here's the issue. I get a loud whistling sound from the intake and rough idle at start up. Once it warms up, it idles fine but I think I am running rich. Are the 30lb injectors too much for a stock engine? Is the throttle body allowing too much air (to big) and causing the annoying whistle?

I was thinking of replacing the injectors to 19lb and buying a new MAF that is calibrated to 19lb injectors.

Thought?

vortechcharger

Anybody have some ideas?

mongolchuck

30 lb injectors are too big. Usually your computer can compensate but it also has limits. When you say intake are you talking about the manifold or the air tube to the throttle body? The tract from filter to manifold typically gets smaller in diameter or stays the same size. If your cold air intake is 65mm and your tb 75 and your intake manifold or egr spacer 60mm then you're causing turbulence and it could definitely be causing a whistle.

88 orangepeel notch

Some throttle bodies have a reputation for a slight whistle at part throttle. My BBK has a very slight whistle at certain rpms and part throttle openings. Not enough to be an annoyance though.

If yours is very loud, Google it and you'll find plenty of info on what others have done to cure it.

And for the rough idle, pull codes to see if any are stored. Then give your vacuum lines a thorough check looking for any leaks.

vortechcharger

Thanks guys...appreciate the advice!