Just fired up the car without any headers or heat exchangers!!!

Okay...

So it is 4 in the morning and I just finished taking off the old 3.0SC heat exchangers...NO BROKEN STUDS!!!!!
and I just put on the oils lines...

Both parts were a bear...the hardest project I have undertaken on my car...I plan to write a more detailed tech article then the one presently on the board...

But anyways...to reward myself for my hard work I wanted to hear a pure 6 cyl boxer engine...so I fired her up for 1 sec...and I shut it off because it was SO LOUD...it was awesome...such a deep throaty and menacing sound...wow!!! I was stunned, and I am still giggling...it was amazing!!!

I know some of you will chide me that without headers the hot exhaust fumes could heat the engine blah blah...it was just for one second, but what a second...

Just wanted to share my mischevious deed...

but I must say although this project was so difficult, and frustrating, it has been the most satisfying...and tomorrow I will clean up the pre-74 HE's and install...and I am sure my first drive will make it 100 times more satisfying...

MJ

Some friends and I started a little 1600cc VW engine once with nothing but bare ports. We had just completed the chassis of a VW drag car and wanted to see it go, but the race engine wasn't ready yet, and we couldn't put the custom fit headers onto the stock engine that we had.

It was very, very loud. I can only imagine what a 911 engine must sound like in that state. You didn't have anything to do with that earthquake in Seattle awhile back, did you?

heh heh, the 4-year-old in you apparently likes his big toys

LOL, yeah, i know about a million other people that like to fire up their cars with no exhaust on them. i have done this countless times, and so has just about eveyone i know that works on their own car.

ever watch the show "Horsepower TV" on TNN? one episode, the guys were working on a classic mustang restoration and right before they put the muffler on they said "whaddaya say we fire this up to see what it sounds like".

heh heh, they had the same goofy grin all car enthusiasts have when they do something like that. when i replaced the catalytic converter on the 924, i took a moment to fire it up with no exhaust. i found that the 924 produces an EAR SPLITTING sound very similar to a Can-Am car. i recorded it too. i was giggling for a good hour after that and my friend a half mile away said they heard it loud and clear.

obin

I had a drag hydro with a blown and injected 427 with 2 1/2" zommie headers WOW was it something a gal was standing a bit close with her fingers in her ears I wicked the throttle and blew her sunglasses right off her head She took three steps backwards real quick!! IT WAS THE BEST!!

I'm told that if you do that too much, it will burn the exhaust valves/guides--can't remember which......Thought I'd givve you a heads up

S

it will mess up the exhaust valves if you do it for too long, or too much.

when i did it on my 924, i had the header on, so the only part that was "free air" was after the header pipes.

before i destroyed my Nissan, i fired it up and heard that mighty 1.6 litre/80Hp fire breathing monster roar... i SWEAR TO GOD it sounded like a little dirt bike. you would have thought that a riding mower was about to drive by if you heard it but didn't see it.

my friend and I were laughing SO HARD when we heard the Nissan with no exhaust. it was just classic! we drove it around the block trying to kill it, but the damn thing would not break. i really wish i recorded it though.

obin

On a 67 Pontiac GTO I had a few years ago, I just finished the engine, put it in the car and had the urge to go for a spin. If I could post the pictures of what this car looked like when I was taking it on its first spin. (no bumpers, grille, trim etc) Needless to say there were no exhaust pipes either. I took it for about a 2 mile journey through an industrial park, open manifolds...I think the whole earth was shaking, you couldn't hear yourself think, unfortunately the cops did not find it as amusing as I did and followed me to my garage.

------------------
___________________
Dante Oliverio
86 Turbo-Look Cab

I've never done the no-headers trick, but when the 3.6 was finally together, we ran it without muffler or cat test pipe. These cars have a very authoritative sound that way.

And now, even with the (Flowmaster) muffler, I still occasionally set off car alarms.

------------------
Jack Olsen
1973 911 T (3.6) sunroof coupe
jackolsen@mediaone.net

When my AMC Pacer's muffler rusted out and fell off, it sounded like a ear-splitting Can-Am car, too! Weird.

The risk is letting cold air warp the exhaust valves if they get a chance to really heat up, then get zapped by the chill. The risk also varies among valve designs and thicknessessessesss.

Never did it with my 3.0, but a fresh built GTO 455 H.O. (yeah Dante!) really shakes yer gutz!

------------------
Charlie Baer
'79 Euro 911SC

You're fortunate you shut it off so quickly. The rush of cold air onto the hot valves can warp them if there is absolutely no exhaust system of any sort in place.

Stephan

Originally posted by 9eleven:
When my AMC Pacer's muffler rusted out and fell off, it sounded like a ear-splitting Can-Am car, too! Weird.

any 2 litre SOHC with no headers will sound the same. for that matter, a 2 litre Can-Am sounds like a FF2000, which sounds like a Cosworth 2 litre, which sounds like an Alfa Romeo 2 litre, which sounds like a 2 litre Can-Am, which sounds like...

and the loop goes on and on.

http://obin_jess.tripod.com/mp3.html

obin

LOL! (Except its the AMC Gremlin, not Pacer!)
http://www.audifans.com/archives/1998/11/msg03726.html

oops, one more thing i forgot to add 9eleven:

if you ever hear a BMW 2002, Porsche 924, Lotus Cortina, and Ford Capri race car drive by... i challenge you to identify them with your eyes closed.

if they are tuned right, they will all sound like a 2 litre Can-Am . all of them are LOUD, and the exhaust sound is SHARP! there is a way to tell the difference, but you have to know what to listen for.

do you know what that subtle difference in the sounds is? how can you tell the difference between those 4 cars if they are all tuned similar and are running on the race track?



obin

Be careful, when hot valves get hit with cold air they bend sometimes. On our race car with short exhaust stacks we plugged them after being on the track to prevent valve problems.

Randy Jones
1971 911

Originally posted by Nick L:
LOL! (Except its the AMC Gremlin, not Pacer!)
http://www.audifans.com/archives/1998/11/msg03726.html

9eleven had a Pacer, not a Gremlin. these are two different cars. also the info in that audifans post is very inaccurate. after i read i i laughed so hard i could barely breathe. if you believe that info, i have a nice lawnmower engine to sell you. it is a driect drop in-replacement for the engine in your 911 with no problem! like the X-Files says "the truth is out there".




obin



[This message has been edited by Obin Robinson (edited 04-17-2001).]

I fried it up one more time this morning on the way to work...the grin stayed on my face the whole commute...and thanks for the bending valves advice..both times I did turn her on, it was just till it turned over and fired once...

But I will be putting on the HE's later...I will let you know how that goes...

MJ

This is so funny and reminds me of when I was a kid. My Dad had a Nash Rambler with a VERY loose tailpipe. The muffler would slide off about once a week and my brother and I thought is was the LOUDEST/COOLEST sounding car ever! We could not understand why he kept fixing it!
Buck

Is the bit about "valves warping from cool air" just a myth? Think of some aircraft motors that have very short exhaust stubs (like the Allison or Rolls Royce Merlin).
Also some P&W radial motors have no headers at all.
Why aren't they bothered?

------------------
Doug
'81 SC Coupe (aka: "Blue Bomber")
Canada West Region PCA
members.home.net/zielke/911SC.htm

Originally posted by 82SC:
I fried it up one more time this morning on the way to work...the grin stayed on my face the whole commute...and thanks for the bending valves advice..both times I did turn her on, it was just till it turned over and fired once...

But I will be putting on the HE's later...I will let you know how that goes...

MJ

PLEASE record this sound! PLEASE! i want to put the sound of your car on my website! do you know how to transfer sound from cassette to a computer? if not, then e-mail me and i'll pay for the cost of the cassette, and the postage... and i'll transfer it here. the sound of a Porsche motor with no headers is something that everyone should get to hear at least once in their life.

thanks!

obin