Hey check out this bellows...

[408WS6]

I have an old boat that is kind of a pet project, but I was looking that this website searching for parts and ran across this exhaust bellows for a mercruiser boat engine:

http://www.amarket.com/im362.htm

Got to thinking, that looks perfect fit for an LS1. I thought about calling these people and getting exact dimensions, but this thing looks so much better than the bellows that we currently have to choose from...

Thoughts?

[jiveass]

but its not smooth...

[408WS6]

that's what she said

[Firebirdjones]

That looks like the stock accordian bellow. So you aren't really gaining anything. It would still create turbulance in the air stream.

[408WS6]

How many brainfarts are we allowed per week? I just used one

[pajeff02]

How many brainfarts are we allowed per week? I just used one

At 43... we are allowed a good dozen.

[408WS6]

word

[Naaman]

That looks like the stock accordian bellow. So you aren't really gaining anything. It would still create turbulance in the air stream.

Are you suggesting that a smooth bellow would ACTUALLY improve performance? Perhaps throttle response...? Maybe a placebo effect...?

[ls1camino]

Are you suggesting that a smooth bellow would ACTUALLY improve performance? Perhaps throttle response...? Maybe a placebo effect...?

Yes...the smoother the flow, the less work the engine has to exert to pull air in, hence more power to the ground.

[Spaz]

Yes...the smoother the flow, the less work the engine has to exert to pull air in, hence more power to the ground.

on paper yes... but there has been no evidence at all that the smooth bellow provides any gains...

[Firebirdjones]

Are you suggesting that a smooth bellow would ACTUALLY improve performance? Perhaps throttle response...? Maybe a placebo effect...?

Yes in a nutshell. Those accordian bellows create air turbulance, something you just don't want in any air track, whether it's the exhaust or the intake.

It's why everyone installs better designed air lids, larger MAF's, larger ported throttle bodies etc....the bellow is just another piece of the puzzle. Anytime you can smooth the airflow there is some gain to be had. On a stockish car you may not see it so much, but on something modded, heads, cam, more cubes, the smooth bellow is definately a plus. Every little bit helps.

I personally just don't see much point in spending money, time and effort installing lids, throttle bodies, and maf's if you don't change the accordian bellow too. May as well attack it all while you're in there.

[Naaman]

Interesting... everything I've read about the smooth bellow said it was a worthless mod. Is there any data that shows the difference between an accordion bellow's airflow and a smooth one's? I saw a graph on LS1Tech that showed the difference in airflow with ported heads compared to stock. Is there anything out there that puts the gains on paper to actually be observed?

[pajeff02]

Frost would probably be best able to answer this question based upon his dyno experiences.

[Firebirdjones]

Interesting... everything I've read about the smooth bellow said it was a worthless mod. Is there any data that shows the difference between an accordion bellow's airflow and a smooth one's? I saw a graph on LS1Tech that showed the difference in airflow with ported heads compared to stock. Is there anything out there that puts the gains on paper to actually be observed?

Not sure there is any solid way to observe it. Mods like that sometimes are hard to measure, especially on ram air type cars, because the air isn't moving over the car on a dyno as it would on the track.

Ya you read alot about the naysayers that it's worthless. But you never see accordian bellows or any other goofy restrictive intake pieces on the really fast LS cars at the track ya know.
I'm doing an LS swap into my blazer, and I'm not using the tiny 3 or 3 1/2" intake track. Since I have the larger LS6 MAF, and the throttle body on the truck engine measures 4" accross, I'm making a custom 4 inch intake all the way through with nice smooth bends. I'll take whatever gains I can get. Details details.

[Firebirdjones]

Frost would probably be best able to answer this question based upon his dyno experiences.

And I think Frost has touched on that before. He even mentioned a while back it's a worthwhile gain removing the MAF screens if you are having him tune it.

[Naaman]

Well in that case, what options are out there? I've only ever heard of the SLP smooth bellow. I think a cool aluminum or stainless steel rig would look sweet, though (assuming that it was bent appropriately... or does it need to be flexible for some reason?).

[pajeff02]

Well in that case, what options are out there? I've only ever heard of the SLP smooth bellow. I think a cool aluminum or stainless steel rig would look sweet, though (assuming that it was bent appropriately... or does it need to be flexible for some reason?).

Fernco from a hardware store.

[Firebirdjones]

Yep Jeff is right. I use the Fernco trick on one 4th gen,,,and I run the SLP smooth bellow on our other 4th gen.

I had been running the Fernco from the hardware store on my wifes car, and at first it had the MAF. I wasn't all that happy about the fitment, just looked like it didn't belong.
I've since switched her car over to an SD tune and got rid of the MAF all together, and now the Fernco looks right at home.

[jiveass]

how much was the fernco?

[Firebirdjones]

~$5.00 at Home Depot.