460 vrooooom!

[Nick-B]

Just spent most of my Memorial Day weekend doing what most other mid-90's 460 owners have done to make their motorhomes get out of their own way and eliminate exhaust leaks.

New Hedman Elite coated headers and a full Flowmaster exhaust system.
Boy, all my muscles are sore but when I fired that 460 up it sounds like the "bad boy" Ford meant it to be.

Maybe tomorrow I'll take it for a test drive.

I was very fortunate that none of the manifold bolts were broken off and they ALL came out. The right side (Pass) manifold had 2 cracks in it and both manifolds were not seated along the bottom edges (lots of soot).

A lot of hard wrench turning but it should be well worth it!

I'll let ya know how she performs on the test drive.

[LVJ58]

Sounds good, what you did should really wake up that 460 and probably let it run a bit cooler.

[5star]

Great Job! Let us know how it does. Did you take any pics of the install?

Mike

[Sammie]

Nick, I just saw the pictures of the headers you installed. Nice looking job. I put Banks headers on my old Winnebago/Chevy. Don't know how close your headers are to the starter, but if they run close you may want to consider installing some kind of a heat sheild. I burned wires on my starter on my first trip out.

Sammie

[Gary - K7GLD]

Quote:

Originally Posted by Sammie I put Banks headers on my old Winnebago/Chevy. Don't know how close your headers are to the starter, but if they run close you may want to consider installing some kind of a heat sheild. I burned wires on my starter on my first trip out. Sammie

I'm considering the same thing for our '88 Winnie 454 - did you notice any, no-doubt-about-it improvements in power, MPG or coolant temps - would you do it again if you knew the end result?

[Sammie]

There is a very noticable increase in power. I could pull hills almost as good as most diesels. I didn't notice any MPG increase because I always drove it like I stole it. Headers will help to get rid of engine heat way better than stock cast iron exahust manifolds. I would definatly do it again if I ever buy another gas rig.

Sammie

[Nick-B]

I haven't even taken it out of the driveway yet.
As Sammie mentioned, pics are in the Gallery.
Motorhomes - iRV2.com RV Photo Gallery

I want to have the time to do a full run with it - freeway, hills, etc. I did take a minute to record the exhaust sound - just for grins.

Take listen to this: http://www.berrysweb.com/Documents/460_Flowmaster.mp3

Sounds nastier than it really is. I placed my laptop about 3 feet from the exhaust outlet but the built in mic on my laptop just can't grab the low end growl of the 460. I grew up with muscle cars so this is music to my ears.

From the driver's seat with the door closed it is very subdued, not at all loud. I imagine that at freeway cruising it will be nearly silent.

[Sammie]

Cool! It sounds nasty Nick. Those guys running stockers will definatly hear you comming and passing.

Sammie

[5star]

Wow that sounds nasty!!! They will hear you coming and move out of the way.... I would anyway....

[RUNDLC]

Great looking install Nick!! Man I wishe dyou were closer I could use a hand on my swap soon!! I ended up with the doug thorley tri-y headers, I can't wait to see how my rig acts with those babies on. How hard was it really? I don't know if I really want to tackle this project, I have heard HORROR stories! I was quoted 300-500 for the install. Would you do them yourself again knowing what you now know.

[Gary - K7GLD]

Being an old hot-rodder, I too appreciate the sound and potential power increase from a good efficiently designed set of dual exhausts - but am somewhat puzzled by the design of the system on the GM 454 in my Winnebago MH:

(click on images to enlarge)



These are not the usual cast iron, but some setup using steel tubing, and these then empty into dual exhaust tubing 2 1/4 in diameter:



Not as good as full individual headers - but how much worse?

My concern is, since what I have now SEEMS somewhat better than a stock setup, would a full-blown setup as this thread displays deliver any significant improvement?

[Nick-B]

Quote:

Originally Posted by RUNDLC ... Would you do them yourself again knowing what you now know.

I would definitely do it again but it is always a gamble on an older engine. I was VERY lucky in that all my manifold bolts were intact and they all came out in one piece. The 460 is notorious for having broken manifold bolts - usually the rear ones - or for having the bolts snap off when you try to remove them. In worst cases one or both heads simply have to replaced. Definitely a horror story and explains why your labor quotes are kinda high.
Are you replacing the exhaust at the same time? The Flowmaster kit is all inclusive and just requires a trim cut or two. A local muffler shop could do a custom setup as well, but I'm guessing it will cost as much or more as the Flowmaster system. I purchased mine thru Summit Racing.
Good luck and let us know how you make out.

[Nick-B]

Hey Gary - You definitely got some odd looking exhaust manifolds. Maybe someone else on the forum can ID them for you.
As for if full headers would make a power difference, I would think so, but not as much as changing from cast iron manifolds. Just not as much bang for the buck.
Love that old Winnie!

[JimElliott]

Quote:

Originally Posted by Nick-B Hey Gary - You definitely got some odd looking exhaust manifolds. Maybe someone else on the forum can ID them for you. As for if full headers would make a power difference, I would think so, but not as much as changing from cast iron manifolds. Just not as much bang for the buck. Love that old Winnie!

88 was the transition year for those (newer) exhaust manifolds, My older 87 still had the log type which didn't work all that well.
My 83 also had the old style log manifolds but it didn't take me long to swap out to the "Thorley tri y's".
Gary, Your 2 1/4 pipes will work OK up to and around 3800 RPM and hand out gobs of torque.
Most of us run 2 1/2 plumbing along with the "X-PIPE" which will dig out even more torque......Mufflers is your choice.

Jim