SBF 302--Torque, Throttle Response, Efficiency--Possible?

[410bruce]

Okay guys, another "theoretical" engine build query.
In the spirit of using stuff taking up space in the garage, could a strong running 5.0 roller engine be made to achieve these three goals?
Parts I have: 5.0 roller block, .030 over, looks like it would clean up easily at .040, new .040 Sealed Power hyper pistons and rings, crank that looks like it would polish up fine, stock rods, set of nice D0OE 351W heads. I know the heads will need to come apart for a valve job, seals, (hardened seats?) etc. and install the correct spring package for whatever cam is used.
Will be using an aftermarket throttle body EFI system, possibly the Summit Racing unit.
Do not have a camshaft, intake or headers/exhaust system.

This "theoretical" engine would be going in my '89 F-150. I have come to the conclusion that I need at least one vehicle that would get some semblance of fuel economy.
The current transmission is a small block C6 but I would at some point like to swap in an AOD.

I would really like to achieve the three listed goals but hopefully not be boring to drive.

I will add, those AFR Enforcer 185 as cast heads look like a screaming deal. 

As always, thanks for any input.

[My427stang]

My general opinion is that there is some separation between dyno/drag racing and street use for EFI

Narrow LSA certainly helps WOT torque on a smaller motor, but less overlap makes them much better mannered and mpg goes up, often making it much nicer to tune and drive

Good thing is, good heads need less overlap, so if you are doing a good head, the gap narrows. AFRs are generally very good in all configurations, but your peak RPM would likely determine if you need a smaller port than a 185. 

If I was building an EFI 5.0, use the smallest and best head for the RPM and displacement. Then cam for the RPM range on that combo, probably keeping overlap below 60 degrees and the intake lobe early, and pick compression to match the combo.  The EFI will be much happier with a little less overlap to boot

[Joe-JDC]

AFR 165s would be the head of choice for a 308 street build.  Joe-JDC

[RustyCrankshaft]

The AFR 165's would probably be much happier on a 308 in an F150. Especially on anything other than a standard cab short bed 2wd - an F150 of any configuration is going to be heavy so it's easy to put too much head and cam in a 302 in that application.

I had a big headlight extra cab 4x4 with an AOD and 302 and the factory untuned EFI it would be upper teens pretty consistently on the highway and 13 or so around town. Stock size tires (I don't recall what size exactly but they were around  31" tall 15). It was pretty tired and eventually I freshened it up, small cam, cleaned up the heads and put a tune in the speed density stock EFI with a small pressure bump. Got 20 a few times and pretty consistently 18.5 on the highway.

[BattlestarGalactic]

My .02....at least on the truck side of it.

AOD would be mandatory.  That C6 will be a gas hog, along with no OD.  Put 3.27 or 3.55 gears in it.

With my last three F150's, I've learned a bit on these 302 powered trucks.  It needs gearing to keep it up in the power, even on the highway or it will constantly have to downshift on grades.  The deeper geared trucks got better mileage city and highway since it took off easier, shifted faster into high gear and didn't have to downshift on grades running 65 on the highway.

I got 20 mpg highway on best days.  18 worse.  Not bad for 25 yr old trucks.  I don't think new trucks do that very often, and if they do...they should for the money you spend on them!!

I put shorties on the '89 truck, no cats and dual turbo mufflers and saw near ZERO effect on mileage.  It was not worth the money, so unless you have the parts already, don't sweat that upgrade.  You don't see enough RPM on that little motor to get the advantage of a bigger, free flowing exhaust. 

Note to self:  You have to drive it like an old man to get mileage.

[410bruce]

Thanks guys. I know the AFR 165s would be an excellent choice but I'm attempting to use what I have--IE the '70 351W heads--and at $1700.00 for the AFRs, not exactly a "budget" choice.
The price of the EFI unit not withstanding, I probably won't have $1700 in the whole engine--maybe.

Have any of you guys ever done up a SBF like this using the factory heads?

[410bruce]

My .02....at least on the truck side of it.

AOD would be mandatory.  That C6 will be a gas hog, along with no OD.  Put 3.27 or 3.55 gears in it.

With my last three F150's, I've learned a bit on these 302 powered trucks.  It needs gearing to keep it up in the power, even on the highway or it will constantly have to downshift on grades.  The deeper geared trucks got better mileage city and highway since it took off easier, shifted faster into high gear and didn't have to downshift on grades running 65 on the highway.

I got 20 mpg highway on best days.  18 worse.  Not bad for 25 yr old trucks.  I don't think new trucks do that very often, and if they do...they should for the money you spend on them!!

I put shorties on the '89 truck, no cats and dual turbo mufflers and saw near ZERO effect on mileage.  It was not worth the money, so unless you have the parts already, don't sweat that upgrade.  You don't see enough RPM on that little motor to get the advantage of a bigger, free flowing exhaust. 

Note to self:  You have to drive it like an old man to get mileage.

Thank you, sir. Great information on the truck side of it.

And for the record, I do drive like an old man. 

[BattlestarGalactic]

Ya, we're all getting to that "old man" status. 

Buddy used to build "budget bomber" 302's.   Stock heads, grind out the bump in the exhaust side, clean up the intake side(nothing fancy).  "F" cam, Victor Jr. intake, and a 600 Holley.   In a Foxbody with a 5spd and 4.56 gears they would run low 12's easily.  No high tech anything.

Now that is not a truck engine, but they can make low buck power.  I'd clean up the stock heads, put a good torque cam in it(powerband 1500-4500), AOD, 3.55 gears and see how it does.  I'd bet the FI would be much better then a carb overall, but with proper tuning a carb would get you by for awhile.

Friend has been doing a LOT of FiTech tuning lately on some motors at the machine shop.  He is quite the whizz at it.   They make crazy throttle response once you get it set up properly.

[410bruce]

Ya, we're all getting to that "old man" status. 

Buddy used to build "budget bomber" 302's.   Stock heads, grind out the bump in the exhaust side, clean up the intake side(nothing fancy).  "F" cam, Victor Jr. intake, and a 600 Holley.   In a Foxbody with a 5spd and 4.56 gears they would run low 12's easily.  No high tech anything.

Now that is not a truck engine, but they can make low buck power.  I'd clean up the stock heads, put a good torque cam in it(powerband 1500-4500), AOD, 3.55 gears and see how it does.  I'd bet the FI would be much better then a carb overall, but with proper tuning a carb would get you by for awhile.

Friend has been doing a LOT of FiTech tuning lately on some motors at the machine shop.  He is quite the whizz at it.   They make crazy throttle response once you get it set up properly.

Thanks again, Larry. I appreciate it.

[Falcon67]

Thanks guys. I know the AFR 165s would be an excellent choice but I'm attempting to use what I have--IE the '70 351W heads--and at $1700.00 for the AFRs, not exactly a "budget" choice.
The price of the EFI unit not withstanding, I probably won't have $1700 in the whole engine--maybe.

Have any of you guys ever done up a SBF like this using the factory heads?

Valve job, replace iron guides with bronze for stainless valves, deck, cut spring seats, mag for cracks - $1100 locally.  Buy the AFRs. way better heads.  If you want a cheap "truck" head, look for some iron GT-40s (not Ps) as those were on the Lightening pickups.   A quote to fresh a used 351C block to ready - bore, hone, deck, line hone - $1700.  IMHO you will not have $1700 in the whole engine.

[67xr7cat]

I'd sell the windsor heads and find a set of GT40 heads. You can find them on explorers from around 1996.  They will work better than the windsor heads and no need for hardened seats.  I'd also go with the factory EFI.  The EFI intake off that same explorer will work well. The factory intake is a long runner intake and will make more torque in the low to mid range. Run a 4r70w transmission which has the wide ratio gear set which helps in 1st and 2nd. With enough gearing you can stop the earth from rotating.  You can run a deeper rear gear and cruise just fine with the overdrive and lockup converter.  You can also make the stall higher for more torque multiplication, but lockup converters tend to get expensive.  Really gear and a modern OD transmission can make a world of difference.  To control it all you need is the factory ECM with a tune. Find a wrecked 96 explorer and swap the engine and transmission, and probably rear gear too.  Remove about 5  lbs. of wire from the factory harness and get the ECM tuned and your done. I know not the answer you wanted, but is practical and low $$$.

[plovett]

The current transmission is a small block C6 but I would at some point like to swap in an AOD.

I concur with this.  I love C6's, but not for fuel economy.  Only 3 gears and heavy rotating components are a double whammy for efficiency.  I think AOD's are heavy too, but the overdrive would help doubly.  First, of course the overdrive will reduce cruising rpms and help economy.   Second, it allows a lower (higher numerically) rear gear.  It may seem counter-intuitive, but a lower rear gear can sometimes help fuel economy, with an overdrive.   I think this allows you to accelerate up to cruising speed quicker and with less throttle.

JMO,

pl

edit:  plus the lock-up convertor in the AOD would add an mpg or two.

[410bruce]

Appreciate all the great responses, guys.
I hate to even admit this but here goes. I already had a 351 roller engine out of a 1994 F-250. Had everything--and I mean EVERYTHING-- for a swap, complete engine intake to pan, all the front dress, complete engine management harness with the ECM and it was a Mass Airflow set-up, not the Speed Density system. PLUS, a 5.0 Mustang T-5 to go behind it. In a fit of trying to get my garage cleared out, I sold it all. Yes, I am my own worst enemy. lol.

Alright, now that I have that off my chest, how about this, kind of out there, idea.

How about a 352? Back around 1986, I picked up a '72 Ranchero GT that the previous owner had shoehorned a 352 into and I was quite impressed how much low RPM torque that thing had. Toploader 4-speed behind it.
My girlfriend at the times dad rebuilt the factory 351C CJ engine and I installed it. As much as I like Clevelands, I kind of missed that bottom end pull and throttle response of the 352.
I also have one of those 3-speed with overdrive 4th Toploaders from a late '70s F-150 i could use as well.
Soooooo, what do ya think?  Would the mighty 352 achieve what I'm attempting with the 302? I'm thinking it might.

[blykins]

Appreciate all the great responses, guys.
I hate to even admit this but here goes. I already had a 351 roller engine out of a 1994 F-250. Had everything--and I mean EVERYTHING-- for a swap, complete engine intake to pan, all the front dress, complete engine management harness with the ECM and it was a Mass Airflow set-up, not the Speed Density system. PLUS, a 5.0 Mustang T-5 to go behind it. In a fit of trying to get my garage cleared out, I sold it all. Yes, I am my own worst enemy. lol.

Alright, now that I have that off my chest, how about this, kind of out there, idea.

How about a 352? Back around 1986, I picked up a '72 Ranchero GT that the previous owner had shoehorned a 352 into and I was quite impressed how much low RPM torque that thing had. Toploader 4-speed behind it.
My girlfriend at the times dad rebuilt the factory 351C CJ engine and I installed it. As much as I like Clevelands, I kind of missed that bottom end pull and throttle response of the 352.
I also have one of those 3-speed with overdrive 4th Toploaders from a late '70s F-150 i could use as well.
Soooooo, what do ya think?  Would the mighty 352 achieve what I'm attempting with the 302? I'm thinking it might.

The 352 will surprise you.  Go back and look at the first iterations of my 352 project when I dyno'd it before rebuilding.  260 hp with a worn out engine and a factory cam is respectable.

[410bruce]

I have kept up with your project Junky Junk with great interest.