Trick Flow 170cc heads too small for a 393?

If you want to be running 87 R+M/2 15% ethanol fuel you better be ready to provide it to the dyno.

There are still some parameters that might not align with your reality, like how restrictive an exhaust is, under hood intake air temp or how much heat your bug covered double row radiator can shed while stuck in traffic.

Modern engine management solutions make it much easier to iterate this process but obviously can't do everything.
Koniegsegg style solenoid  actuated Freevalve technology is really interesting in that just about any cam profile and timing resides in the EMC.

Yep, I plan to have the tank full of 87 pure gas when he tunes, but will also ask what I need to do to optimize for 10% ethanol.  But I think the main thing I have to do there is to change the desired AFR from 14.7 to 14.1.

As for the Koniegsegg Freestyle, that is interesting technology.  But it boggles my mind at how many more variables it would introduce in the EEC setup.  I've been perusing the ones in Big Blue's EEC and that is waaaay more complex than I can get my head around.  But adding the valve timing would be even more overwhelming.

However, for people who understand it and have the right facilities to test and tune, the possibilities are enormous.  Shut down cylinders when not needed.  Advance or retard the timing as needed.  Change the overlap, open/close timing awa the speed for that, etc.  

15% is coming....  

And you're never really tuning for actual fuel ratio, just the lambda.
The A/F : is derived from that.
It's much easier to do that by changing pulse width than pulling a carb apart to change jets.
Same for ignition timing if you need to pull the reluctor to get at the slots and springs.
Dyno time isn't cheap....

I was speaking to the OP's goal of 15 highway on 87 pump gas.
And kind of tying back into the fact that heat is what pushes the crank around.
Alcohol doesn't burn hot.

E85 can certainly make huge power with enough compression (or induction pressure) but with optimal A/F R's below 10:1 you have a very thirsty vehicle.

Well after reading through the thread again I am now thoroughly confused.

I still don't know if I should stroke this thing or not. I'm finding a couple of kits that would give me about 9.5:1 compression. That may be good for 87, and if not I would think 89 would work well.

How about this one: Why wouldn't a mild 393 (let's say 350-375 HP & as much torque as reasonably possible) with good heads, roller cam, etc and a 5 speed net better MPG than a tired, over-cammed, stock head-ed, less efficient 351 with lower CR and a 3 speed? Let's also assume that I swap the 4:10s in the rear for 3.54s.

It seems like the 393 would surpass the MPG potential of the 351 based just on it making considerably more torque down low and having an extra 2 gears to play with, even though it has 42 more cubes.  

I know power takes fuel. I'm just wondering if I'm missing something else in this equation.

Gary Lewis wrote

Another reason to have your truck dyno'd is to get the ignition timing dialed in.  While the Sniper Stealth system can adjust timing, I don't think it knows what timing is best.  So having the truck tuned on a dyno will let the timing map be tweaked so you get max power and max economy w/o pinging or detonation.

Correct, but I wont be running timing control off the bat, I will just stick with my custom curved D.U.I. DSII distributor then I will switch over to the timing control once I get all the bugs worked out.

I don't have any doubt you can make more power and get better mileage with a new bigger engine than a forty year old clapped out 351 in an F-350.
I don't know if you're going to best 15 mpg at 70. Because the truck is a barn door and fairly heavy to boot.
Definitely not with 1:1 4th and 4.10s on 32" tires.

If you're looking at a roller cam I'd suggest you just start with a later roller block ('94... I think???)
My cam advice would be seriously out of date.

Maybe you "need" aluminum heads to deal with 9.5:1 and 89 octane???
But it seems they all have much smaller chambers, and you are already increasing stroke plus having to zero deck in order to get quench.
Do you really want big dish pistons to correct compression?
It's my understanding that a stock 351W is right about 8.4:1. Can anyone correct me or back me up?  

A lot of your ability to stave off detonation depends on your ignition curve and the cam you choose.
I know Gary and a few others on here have had theirs curved by Scott at Parkland Performance.
Additionally you can run a colder thermostat and plugs, because every little bit helps.
But you definitely don't want a big cam with a choppy idle if you want fuel economy or to use your truck for "truck stuff"

Also ditch the RPM intake and get the regular Performer or its equivalent with a 600 cfm carb.
You don't need power 1,500 to 6,500 if you want fuel economy and intend a 5,000 redline.
You need good VE from 600 RPM if you want your F-350 to pull through the gears.

And I still think you're better off with a 408 than a 393. (Edit: Specifically a 6.2 rod and a 1.280(ish) piston, depending on what it takes to square your block)
Someone with a program would have to run the numbers with their rod ratios and slightly different compression because I don't have a Windows machine any more.

Close enough on the CR.  I'm seeing 8.3 in the spec's.

Thanks Gary!
I'm not a Windsor guru,  as you know...  

I think on the highway with my old smog 302 in my flareside I was getting 15mpg highway at 70 mph.  Im hopeful with a fresh transmission without the slip I currently have, swapping the 2.75:1 axle ratio to 3.25:1 axle ratio to go with my 31x10.50-15 tires I am hopeful to break 15 mpg highway.  Even if its just 18 I would take it.

Crane had some pretty nice roller cams for OE roller blocks.  I am glad I picked mine up from them before they went under again cause what Comp offers I think is sub par to what Crane offered.  Crane has dual pattern roller cams while everything Comp offers is low lift (under 0.500") and is a single pattern.

I personally was going to use parkland for my distributor but the more I thought about it I decided to just get a D.U.I. DSII distributor curved by them as they use a OE ford housing with a full length bronze bushing and the cardone distributor I had I just wasnt feeling it on a engine with this money money in the build and cheaping out on a $40 distributor.

But it is right, you want as small a cam as possible no more than 112* LSA, some big RV cams I read can be to 110* LSA but 112* to 114* LSA is where most RV cams are with stock cams being 116* LSA.  The Crane cam I got is a 112* LSA and was the smallest tow cam they offered in OE roller design.  It also has a 107* ICL which will make it a very responsive snappy engine at lower rpm.

The intake is another thing I dont know how many people chastised me for going with the plain idle - 5,500 rpm performer intake and that I should have gotten the performer rpm intake cause it doesnt hurt low end power but will make more top end power than the standard performer which everyone swears drops off at 5,000 even though Edelbrock lists the power band for the performer as idle to 5,500 rpm.

On the induction if going carb I would shoot for 500 to 600 cfm, I actually have a 600 cfm summit carb brand new in the box I planned on using but then I decided to go with the sniper instead which is 870 cfm which if carb would be way too big and have horrible throttle response.

If I were building this engine I would probably build it with the same Crane cam I am building my 302 with cause I feel its a great all around cam for a truck that is used on the street.  Description states "Good low end torque and hp, good idle, daily usage, performance and fuel efficiency, off road, towing, 2,400-3,000 cruise rpm, 8.75 to 10.0 compression ratio advised" with a power band of 1,400 - 5,400.  I dont know about his gearing but I know at 1,500 rpm I would be doing 40 mph in the city.  Crane had some other interesting roller cams around the same 1,400 - 5,400 rpm range but they just lack the 0.520"/0.542" lift the one I have which is what you really want with AFR heads.  If you are spending the money for AFR heads you would want a cam with at least 0.500" lift as AFR heads flow best 0.500" - 0.550" lift.  There really isnt a whole lot of options out there when it comes to roller cams for trucks really, everything is speed density stock cams or they are mustang inspired letter cams that are more mid range and up cams.

Rusty, the OP has a 350 (heavier frame, suspension and axles, more air under the chassis) and a 4.10 ratio in a suspected D61 axle.
This is why I said I doubted that it would get to 15 highway.
Gearing change and a 5-speed Tremec is certainly going to help, but still a big challenge even if you drive like you have an egg on the throttle pedal.

Shame some other cam company hasn't picked up on that grind.
I do understand that there isn't much demand for a cam like that on an extinct engine, especially when engines have evolved so much in the last 30 years.
It probably isn't worth it for them given the very limited market.

SubSonic wrote

It seems like the 393 would surpass the MPG potential of the 351 based just on it making considerably more torque down low and having an extra 2 gears to play with, even though it has 42 more cubes.  

The problem I find with this statement is that "MPG potential" is not a fixed thing. It all goes back to how you drive it.

I am in total agreement that a 393, driven gently, could surpass the MPG of a 351. This was the lesson to be learned from the Prius and the BMW - if you have to wring a smaller engines neck to get it to produce power  (the Prius) but can extract the same vehicle performance with a larger engine operating at a more leisurely pace (the BMW) then the larger engine can perform better, MPG wise.

Now, if you decide to wring the larger engine's neck, well, it's going to lose that MPG advantage.

Pete Whitstone wrote

The problem I find with this statement is that "MPG potential" is not a fixed thing. It all goes back to how you drive it.

I am in total agreement that a 393, driven gently, could surpass the MPG of a 351. This was the lesson to be learned from the Prius and the BMW - if you have to wring a smaller engines neck to get it to produce power  (the Prius) but can extract the same vehicle performance with a larger engine operating at a more leisurely pace (the BMW) then the larger engine can perform better, MPG wise.

Now, if you decide to wring the larger engine's neck, well, it's going to lose that MPG advantage.

I agree with that statement - to a point.  And that point is some place below 7.5L.  I know one of them that is operating leisurely and it isn't going to get what a 393 or a 351 could get, in spite of being a well-built engine and fuel injected.  There's just something about the 460 and efficiency that don't belong in the same sentence.  Oops!  I did it.  

Yep, I think he can hit 15 to 18 highway with the proper setup even in a F350.  Given that wont be pulling a trailer or hauling a load.

Comp supposedly bought Crane out and thats it.  You go to crane.com it redirects you to comp cams and they have no mention of releasing the Crane grinds or a listing of them on their website.  I put my cam card up so in the off chance if my cam gets damaged I am hopeful I could use this cam card to get someone to custom grind me this cam again.

lol engine builder I know told me to just get a stock 460 and drop it in my truck vs trying to hotrod build a 302.  I went uh no I want a blend of more performance and fuel economy than the smog 302 gets lol.

Scott at Parkland has someone to grind cams for him..
Used to be Delta. I don't know if it still is.

"Efficiency" and 460 can definitely be in the same sentence!
But big engines burn a lot of fuel.
And you never asked Scott to build a tea totaller.
I said that in my very first reply. Something like, they are "a different kind of beast"

Yes, it is different.  And yes, it is a beast.  So I guess that makes it a "a different kind of beast".  

And it drives sooooo much better with EFI - when the EFI is working correctly.  Whole different engine.

Scott planned that whole engine around EFI!
And Bill has been pushing since you got the cam broken in.  

Yep, but I had places I wanted to go, like Ouray, and wanted to use the truck for a while.  And I knew it was going to be down for several months while installing the EFI.  Looks like it took right at 3 months to get it going, and it'll take a bit longer to get sorted.

I'm not saying it isn't "A good thing" that you got to enjoy Big Blue....
Just now that he fits your sig (and the builders optimization) he is running smooth and strong.