Rick's 5.0/C6 swap 1985 BII

[Mechrick]

I've had my BII on the road for seven years now. It was originally put together with a 2.3L/Weber 32/36 and a TK4 speed. A good writeup is on FordSix, they were gracious enough to allow it in the Orphan Inlines section.

https://fordsix.com/viewtopic.php?f=13&t=72863

Working from home during the pandemic gave me time to experiment with a turbo. Detonation with the turbo prompted me to pull the head (I was going to relieve the chamber and install a thicker head gasket to lower compression, but then this:

Okay, time for a new engine.

I *really* wanted a small diesel. The cost of such a swap deterred me. I have a 5.0 out of a pickup, and a C6/NP208 out of a full size Bronco. I decided to use what I have.

An advantage of the V8 is simplicity. the four with injection is a bit more complex than what I want in an Overlander.

The grungy 5.0:

Mocking it up:

 

[Mechrick]

One of the things I worried about was A/C plenum clearance. Turns out by bolting the trans to a crossmember, then heating the plenum while jacking the engine up with an engine hoist easily provided the clearance needed. The 2" body lift helps immensely.

I built the transmission for a full size Bronco years ago. It got E4OD six pinion planetaries and a full Torrington roller bearing conversion. The E4OD planets change first gear from 2.46:1 to 2.71:1. Installed a shift kit to firm up the normally slushy Ford shifts. It's a stout piece. Plan is to get it on the road, then hunt down an AOD core and give it the same treatment with 4R70W internals.

Engine will be held in with convertible Mustang mounts. Decided on Explorer accessories, and will probably run Explorer manifolds to start, although I don't like the looks of them. The explorer accessories add 2 inches of clearance in the front of the engine.

Explorer crank pulley on left, '90 pickup on right:

Front covers are different, and water pump-specific:

Dubious-looking Explorer manifolds:

 

[Junglejoe]

Hell yeah. Might look into the sn95 mustang FEAD. Its a little long the the explorer but shorter then the truck or foxbody setup

 

[Mechrick]

Hell yeah. Might look into the sn95 mustang FEAD. Its a little long the the explorer but shorter then the truck or foxbody setup

I've already got most of the Explorer setup. Just need to scrounge a P/S reservoir and A/C compressor.

 

[Mechrick]

Where was I? Oh yeah, rebuilding a 5.0L.

Block had to go .030-oversize. I measured the old piston/pin, it was 751 grams. Speed Pro hypers are the same weight so I ordered them.

Half of these pistons were 750 grams and half were 751 grams. Connecting rods were 566 to 568 grams, so I matched the heavy pistons with the light rods. Total engine balance should be within two grams end to end (assuming factory balance was close). I usually lighten and polish stock connecting rods, but that would have hosed the balance. I did swap the rod bolts to ARP wavelocks.

I wasn't happy with the pin bore on one of them, so I ordered one C80E rod from Rockauto. What showed up was a F2TE, and the gram scale shows they weigh exactly the same.

The camshaft is a stock Mustang 5.0 roller.

I built a pin stop for my mini mill table. After heating the pin end of the rod to ~430 degrees F, the piston pin slides right in.

Crank chucked in the lathe to make polishing/cleaning easier...

Installing rings to pistons...

Checking piston bores and ring end gap. Ideal end gap is .016"-.018". These are not file fit rings, all end gaps were .020".

Tapping front oil galleries for screw-in plugs...

I drilled a .046" hole in one of the gallery plugs, hopefully to spray oil on the distributor gear.

Assembled short block...

 

[Junglejoe]

Coming along nicely!

 

[Mechrick]

Got the heads done this weekend. I toyed with the idea of using GT40/GT40P heads, but the smaller intake ports of the E7TE truck heads *should* be better at low RPM. I did spend a few hours reworking the bowls and short side radius. The exhaust ports are atrocious.

The exhaust ports have a shelf in the port where the guide boss protrudes. It has the effect of making the roof of the port a very turbulent area. The correct fix would be to reshape this area and rework the roof of the port to take advantage of it. Problem is there is water in there somewhere. I flattened out the guide boss and left the roof of the port alone, except for a slight flattening of the thermactor bump.

351M/400's have a similar type of exhaust port, with the water jacket drooped around the guide. I think it's to help keep the exhaust valve cool on a truck engine that may spend time at WOT.

True 351 Clevelands and GT40P's have a lovely exhaust port shape.

The rest is standard procedure, grinding valves and seats, a quick valve lap to verify seat contact and width, cleaning the grungy rocker gear, and a bit of paint.

I ditched the goofy Ford exhaust rotators and short springs for intake rotators and springs. The exhaust valves have the lock groove cut .100' lower than the intakes. I may run into coil bind. Will soon see.

 

[Mechrick]

Yep, coil bind with the long springs on the short valves. The Factory exhaust springs are shorter and the exhaust rotators result in a shorter installed height than the intake retainers. I switched back to the stock parts.

New springs and retainers would have been lighter and had higher seat pressure. This is not a good idea with stock Ford two-piece valves. The hardened tip can come off with higher spring loads.

Since I was going to run the 4 degree advanced setting on the crank gear, I threw a degree wheel on and took some notes. This cam is a 1995 Mustang HO factory grind. Here is what I got:

Advance: 4 degrees
_______________ Intake: Exhaust:
Duration @ .050" 208 210
valve open .006" 20 BTDC 70 BBDC
valve close .006" 75 ABDC 7 ATDC
valve open .050" -8 BTDC 45 BBDC
valve close .050" 36 ABDC -15 ATDC
Centerline 102 120
Lobe separation angle: 111 degrees

Installed straight up, the .050" numbers would be:

IVO: -12 BTDC IVC: 40 ABDC
EVO: 41 BBDC EVC: -11 ATDC

Note: Someone else checking this same engine with a different degree wheel would get different numbers, but these should be correct within 2 degrees.

The intake lobe is wildly asymmetric. The close ramp is super mild. I checked the centerline angle .050" from peak lift. If calculating centerline from .050" off the seat numbers, intake centerline becomes 112 degrees and lobe separation becomes a more conventional 116 degrees.

 

[Mechrick]

Went to install the oil pan and it hit the oil pump. This engine had bottom end work done to it in the past, the crank was .020"/.020". The pump was a high volume unit.

Amateurs.

There are engines that a high volume oil pump replacement is a good idea. Buick 231's and Ford 460's come to mind. Or engines that have higher bearing clearance (.003") for high RPM use. My bearing clearances were .0018" on the mains and .001" on the rods. 5.0L's don't have oil pressure problems. I put a stock volume pump on.

The 5.0L uses a puny 1/4" oil pump driveshaft that can/will twist off on a cold January morning with a high volume oil pump installed.

 

[Mechrick]

Clearance needed to clear the driver's side TTB pivot bracket...

Megasquirt removed:

Will it fit?

 

[Mechrick]

Voila! The Covid 306 has a new home.

 

[Mechrick]

Researching radiators. The BII opening in the core support is roughly 24" wide by 18" tall. There are condenser fittings on the passenger side.

Explorer V8 radiator core is about 23 3/4" wide by 20 3/4" tall. Uses goofy U-shaped mounts.

1996 Grand Cherokee radiator core is 22 1/4" wide by 19 1/2". Uses bottom pin-type mounting (I like). Also uses 1 1/4" upper hose nipple (Explorer is 1 1/2").

Trans cooler lines at the trans are standard brake line type flares. I would like to use these on the radiator side also.

-Any suggestions?

 

[Mechrick]

HEI distributor. I feel Durasparks are actually better ignition systems, but you can walk in any parts store in any small town and buy coils caps rotors and pickups for HEI's. The large air cleaner didn't clear though.

 

[BlackBII]

Really good work here! Looking great. Love seeing these old Bronco II's given a new life with a big engine.

I dig the smaller air cleaner, gives it a more factory look from that era.

Love it!

 

[Mechrick]

The air cleaner is off an S-10 pickup. I need to run a ducted system in Vegas in the summer.

I was missing the water pump pulley. Evidently not available new anymore. Thought about a visit to the junkyard (need to go grab driveshafts anyway). Decided to whittle one of the E9TA-8A528-AA pullies I had (off a late 80's 5.0L) down to fit.

I'm hoping the crown of the pulley doesn't contact the belt or it will kick off.