1970 Mach 1, very loud at idle

hello all.
I just purchased a restored 1970 Mach 1, I did not realize how loud it was before purchasing it and wondering what can I do to make it as quiet as possible.

Overall the vehicle is very loud, starting the Engine in my garage upset my neighbor
and I realize that nothing can be done about this, but the vehicle at idle is
loud and was wondering if it would help changing over to a stock muffler and exhaust system.

I am also interested in converting to a fuel injection system, as a side effect would this help reduce the noise when starting the engine ?

I have very little knowledge of cars and was wondering
if I could get some advice.

Here are some of the specs.
351W bored/stroked to a 428
Holley 750 Double Pumper with electric choc
New dual aluminum intake.
2-1/2" exhaust with shorty headers, H-pipe and Flowmaster 40 mufflers.

thank you
Van  

change to a quiter performance muffler but dont use a stock exhaust system with that stroked out 351W ! changing over to fuel injection is gonna require some tuning to get the fuel curve right for that engine and could be costly if you have to have someone else do it, aint nuttin wrong with a Holley(GOLLEY) carb , I only use Holleys ! Golley ! P.S. I have an old worn out set of the discontinued Edelbrock 5560 RPM mufflers that are like straight pipes I have never had a complaint and they are can you hear me LOUD ! How does that 428 run ? I bet its FAST !  

thank you "shiftthis" for the advice.

I have had the Mustang now for a few days and no opportunity to take it out.
Maybe this weekend. Thanks for the muffler advice.

What about adding power steering and power brakes ( currently disk in front and drum in rear), you think doing this would take away from the value of the car,
I could not get a clear answer from the dealership.

As for fuel injection, you see problems if I had a professional do it ?

thanks
Van  

I never use power brakes , dont like them. I use Willwood SuperliteIIA 4 piston calipers x4 wheels w/1.25x12" Coleman directional vane rotors and roadrace and can lock up 11" wheels easily. I do like power steering cause I have 11" wheels in front but I use a custom power steering servo , the factory power steering unit works good and as for the value of the car all this is bolt on and can be changed back if you sell the car. As for fuel injection it all depends on who installs and calibrates it , & the only shop I would recomend is MAECO MOTORSPORT in Northridge,Ca. ph 818-701-1923 talk to Mike the owner they build and roadrace early Shelbys and Mustangs and I have ben friends with these guys and had them do work for me since 1994. They also have a website.  

I think flowmasters are generally a loud muffler anyway.  You could go with a Borla or Magnaflow which are quieter.  Go to cruise ins or car shows and listen to some cars and find out what they have.  I have an 03 Cobra and I think the factory exhaust on it is too quiet.
Or just tell your neighbor to lighten up and quit being a baby.  

No disrespect to you Van, people like different things but if you dont like that rip snorting pony you got,maybe your in the wrong hobby. My neighbors have come to almost expect the sound of a small block starting its life thru straight pipes and listening to that is one of the few pleasures this old man gets with my bad ears. A stroker big windsor motor like you have oughta sound like that and putting stock mufflers on that would be like putting a 32B bra on Holly Madison ,,, you know what I mean. Some things are meant to be enjoyed with a visceral reaction and that barking thru the flowmasters is one of them. Before you cobble up that fine machine maybe you should look at the new lincolns or maybe a BMW or something, trade it in and let some other guy enjoy that horsepower symphony in the morning,,,,,,, I will trade you my focus.  

I agree with mechanicalguy48 that your neighbor is too touchy or maybe an enviormentalist that would like to see that stang sent to the scrap factory, thats just my guess. My 393 stroker windsor is just barely street driveable and the exhaust is basically straight pipes but no one including the cops has ever said anything and most of the Harley motorcycles I encounter drown out any noise my stang makes ! Yes most Harleys are way louder. If you really want the car queit I would suggest checking the engine code and putting the factory type engine back in with stock exhaust and selling that 428.     some stuff in my 393 > Bryant Racing Chromemolly forged crank 3.9" stroke , JE custom made pistons 4" bore , OLIVER Racing 6.2" chromemolly billit standard weight rods , AFR 205 58cc heads , Comp Cams custom ground roller , GOLLEY (HOLLEY) 830 HP DP , AVIAD 10 quart roadrace oil pan , custom FPA 1.75"x34" wide bolt pattern headers , internal balanced , WILSON prepped Air Gap intake , etc. , big input/output smallblock close box toploader w/vintage HURST supershifter2(push down 4 reverse) , & a 3.00 locker in the back for my extra pair of shoes !!!  

Thanks everyone for your suggestions and comments, the Mach 1 will crank, has spark, fuel smell all over the place but will not start, changed the spark plugs and it started just "once" and now its dead again. That solves the problem of my neighbors complaining.

Van  

sounds like a fuel line leak or a stuck float in the carb or fuel pump gone bad.