I just bought an ambulance! 1987 E350 chassis with a Braun drop-on aluminum ambulance body (amazingly well-made). 460, C-6, Dana 70HD with limited slip. Astoundingly (I have to guess this is the aluminum body), it isn't nearly as heavy as I would have guessed, scale weight on the title being 4630lbs. Seller asked me what I planned on doing with an ambulance; I told him I'm starting a ghostbuster business (actually I'll be converting it to a camper/tow van)
It's going to be a gas-hog, but I figure I can make it a little less thirsty. The 460, even in the smog-engine years of the Seventies, had a reputation of being fairly fuel-efficient for its size. A couple of things you could do back then were to reset the cam timing to "straight-up," and to grind the big lumps out of the exhaust ports. And other standard hot-rodder tricks that make an engine more efficient, meaning more power or better economy, depending on how you were using it.

The next step, in those days, was to swap in 429 heads for more compression (better to do this during a full engine rebuild so that you could deck the block to get a properly-tight squish height, to help stay out of detonation).

But maybe this would not apply to a newer 460. In the early-to-mid-eighties, many engines got their heads redesigned. The old inefficient open-chamber smog heads got modified by the factory for intake swirl, and a little more compression. So maybe the heads on this '87 are a more modern swirl design, and maybe 429 heads won't offer much???

Please tell me about my '87 heads. And about what heads (Ford or aftermarket), if any, might be preferable for best fuel efficiency in a work-truck's rpm range.

Also, do you know if any of the header manufacturers make a tri-Y header for the 460 in E series vehicles?

 

Seattle S, You're in a good area to get some great info. Scott Johnson some times posts on this forum and is the owner of RPH in Tacoma. He has a web site and I'm sure he'd be glad to let you know about heads. As for headers... Stan's headers in Auburn builds TRI-Y headers. I put a set of his headers on my motor home 15 yrs. ago and they are still doing great! He also has a web site. Check them out. Congrats on your new project.

 

'87 is still carbureted.
E7 fuelie heads went on '88 model year vehicles.
Use a timing set from a later EFI engine to get a roller chain and straight up timing for your carbureted engine.

Zero deck the block but forget about pre-emissions 429 heads unless you are willing to run AV 100LL or race gas.
10.5-11:1 compression is WAY too much for modern fuels.
Stick with a Max of 9.5:1.

Aluminum heads do much better at staving off detonation.
Trick Flow are nice.

Scott did a bunch of work with the ProComp head castings, but mentions lousy assembly and components.

He also has made a run of Non-Emissions CI D3's for those classes that demand an iron head.
Check his website for pricing and availability.

Add an aluminum dual plane intake manifold if emissions testing in your area allows it.
I don't know enough about the E-Series scene to say if there are headers comparable to the Thorley Tri-Y's

Scott has great instructions and templates for home porting D3VE heads on the ReinCarnation website by subscription.
He also has instructions for recurving the emissions era distributor.

 

Thanks, Jim and Bob, what you've told me is a big help in googling for further info, particularly on the D3VE heads. I have taken a short look at Johnson's site (www.reincarnation-automotive.com) and will go back to it.

On zero-decking, by which I assume you mean milling the block deck enough that the outer edge of the piston is even with the deck (and which I understand would typically take a roughly .020" cut), what is the resultant squish-height (which I assume is going to be the same as the compressed thickness of the head gasket)? I ask because some guys are a lot braver than I am; super-tight squish doesn't seem like the best idea for a big-block that you want to go 150K miles without drama. My uninformed guess would be that something around .045" should be fairly safe and still provide most of the available benefit of squish. Yes? No?

I have some other questions relating more to the vehicle than to rebuilding a 460, so maybe I'll put them in another location on FTE (there's one called, "1968 to 2013 Full-Sized Vans."). But I'll come back here too.

Thanks again,
--Smitty

 

Post '79 blocks usually leave the pistons about .033 in the hole.

A regular FelPro head gasket is about .040-.045 when torqued.
This is tight enough to quench the chamber and cause turbulence.
.078" not gonna happen...

Don't worry so much about clearance on a truck engine.
It's the high revs of a race engine that cause rod stretch and other clearance problems like valve float.

 

Well yeah, I suppose that if at 150K miles my bearings have all loosened up to .040" total lash, I just might have things to worry about besides squish . . . .


However, I am now getting somewhat cold feet. One of my advisors in the Full-Size Van section has convincingly expressed skepticism at the listed scale weight. He and I are now thinking that the 4630lb figure must have meant the 1-ton chassis and cab and all the heavy running gear LESS the drop-on body, and that the complete vehicle must go something over 6000lbs, empty. Sober consideration now suggests that even with all the engine and transmission improvements I could make, this rig is going to be pretty expensive to drive long distances . . . .

 

My truck went 280K before it finally spun a bearing.
Main clearances are supposed to be .0015", so you are talking about 60x too much.
There would no oil pressure long before that!

It's a 460, pushing a giant 'brick'.
NO ONE will suggest it will ever be a fuel sipping econobox.

The C6 is going to turn a lot of power back into heat.
The ROI of installing an E4OD and U.S. Shift (nee Baumann) standalone controller just isn't there.
You may break into double digits on the highway with a tight torque convertor.

 

That was actually a joke that I was making (clearances). Nor was I expecting an econobox, just thinking about taking the brick (now understood to be a very heavy brick) from bad to less-bad to an acceptable compromise. I'm still thinking on it.

I read a write-up on somebody who had installed Level 10's rolling-element thrust bearing for the C-6, and he reported a small but real gain in fuel economy. www.levelten.com

 

I've always been interested in a retired ambulance for a jobsite vehicle.
Headroom snd power inverters make sense to me.

Can you post some pic's?

 

I can barely do THIS. Google "braun ambulance body on 1987 ford e350", go to Images. If you get the same screen I did, look at the first (left side) photos on rows one and seven. Very sorry I can't help you more.

 

That's pretty cool.
Does yours have the aluminum rims too?

 

That's the one.
However, don't be fooled by exterior appearance, you cannot stand up straight in it; the floor's too high. You certainly can walk in and out to access whatever you're after, but you are bent over at the neck. This could be a much better around-town work van for you than ordinary vans: you have those very handy outside-access doors on one side like a service-body pickup, but you can carry everything out of the rain and somewhat secure from thieves. The top is not so high that you couldn't make a rack and carry ladders or conduit. And with a 460/C-6 you can tow as well.

 

My Tow truck is listed around 4600 on the title, but it's heavier, so I'm guessing that weight is the empty chassis.

 

D70 rear in the Ambulance package,

I'm betting that is the weight of the cutaway as it came off the line.

 

Sometimes I feel like a broken record...

Upgrade your ignition system, I got more MPG gain out of my full ignition system than I did from my ZF5 swap. My current setup is happiest with the plugs gapped at 0.090"