Help me with my engine choice...351W for 72 Bronco

[ilovemaui]

The roller blocks seem to wear better. When I rebuilt my 302 with 88,000 miles it did not even need to be bored and my 351 with over 100k only needed a 30 over bore. Look for a F4TE casting if you go 351. Mine came out of 1995 Bronco.

 

[KyleQ]

The 69 blocks also had a lower deck height which causes problems with compression and making any changes down the line. You want a roller 351W from a 94-97 truck/van as they come with great roller cams. In those motors you can use a 302 roller cam which opens the door up to a HUGE cam selection.

It is also as easy as getting a truck 351w lower, bc adapter, car upper and toss a Mustang harness and PCM on it and you have a fuel injected roller 351W... food for thought

 

[broncnaz]

The wear issue is more due to EFI than anything. 100K and needed a .030 overbore is not so great my carbed 302 went 177K and probably could have done a .020 overbore.

 

[KyleQ]

The wear issue is more due to EFI than anything. 100K and needed a .030 overbore is not so great my carbed 302 went 177K and probably could have done a .020 overbore.

I don't see how the fuel is introduce has anything to do with wear - how many factory fuel injected vehicles are out there pushing 200k without a rebuild?

 

[Kauai72Bronco]

sweet...so I can get a 95 351w longblock from Ford for around $1700....if I go this route, what would be a good cam to swap in?

 

[Amac70]

im running a comp cam 35 510 8 but your stock heads will not support it with out a bit of work. but its is a very nice all around cam.

 

[broncnaz]

I don't see how the fuel is introduce has anything to do with wear - how many factory fuel injected vehicles are out there pushing 200k without a rebuild?

That was my point most EFI engines go a lot longer. carbed engines dump a lot of raw fuel into the cylinders and over time build a lot of carbon and acids up in the oil. Where a EFI engine doesnt do this as much. Take most carbed engines and at 3000 miles the oil is black most EFI engines at 3000 miles and the oil still looks good.
Some one stated that there 95 351 had to ovebore .030 at 100k probably wasnt EFI for long or something was really wrong for it to need a overbore at 100k. heck even most carbed engines will go well over 100K. My 73's carbed 302 went 177k before I rebuilt it.

 

[broncnaz]

sweet...so I can get a 95 351w longblock from Ford for around $1700....if I go this route, what would be a good cam to swap in?

Depends on what your driving needs are the stock 351 roller cam is a good cam. go much bigger and you may need to regear the axles. Picking agood cam can be tricky a lot of factors are involved. it really makes or breaks the engine. but for a mild build the stock roller cam is fine.

 

[KyleQ]

The stock 351w cam with GT40 heads makes real good torque, I'm leaving the factory cam in there myself...

 

[Ranchtruck]

These are supposedly the cam specs on the 351w roller:
F4TE roller cam, '94+ truck and Explorer

256/266 adv duration
0.422/0.448" lift with 1.6 rockers.
203/216 dur at 0.050"
106 ICL 126 ECL

Valve timing seat to seat
IVO 22 IVC 54
EVO 79 EVC 7

Valve timing 0.050"
IVO -4.5 IVC 27.5
EVO 42 EVC -6


Fuel injection makes a massive difference in engine wear. I've got a 96 F250 351w on the stand with over 250k miles. The factory crosshatching is still showing on all the bores. The truck had a plow frame on it too, so you know it was used hard. Seeing the crosshatching with over 200k is normal with EFI engines, seeing it over 100k with a carb is surprising. Running rich washes the oil from the cylinder walls and thins the oil in the sump, leading to increased wear. It's very hard to get a carb to run the right mixture all the time.

 

[KyleQ]

^^^

Exactly, I took apart a motor that I was told had 180K on it and it is in perfect shape. Cross hatching still visible

-

 

[65 mustang]

Can anybody confirm or deny that Ford used poor iron in the mid 70's to early 80's in the small blocks? My 78 punched .040 over wore groves in each cylinder from the oil rings nylon keepers. Maby just a bad block? Scott

 

[Kauai72Bronco]

I ended up ordering a built 351w from Promar Performance Engines. Includes Mallory distributor and plug wires, black finish Edelbrock Intake and hi flow water pump. Ill post some pics and a review when it gets here

 

[jckkys]

The '69 351w was kind of special. They came with better heads with the same size valves as GT40s,a great although heavy 4v intake that produces tons of low end torque and is easy to fit under the hood,and they use the same ps & alternator brackets as the EB 302.They even use the same water pump. The adapter pieces that bolt to the heads permitting the use of 302 alternator and ps brackets are unique to the '69 351. I'm not sure if the crank balance is 28oz like the 302 so the harmonic balancer may be unique but it takes the same pulley and timing pointer. To the casual observer the complete engine with accessories is hard to tell from an original 289-302 with a 4v added. I did a similar swap using the original exhaust manifolds, single muffler,and original air cleaner. The low end torque increase made it all worth while. The later blocks with one piece rear main seals are a good deal and some made in the 80s have the same 28oz balance as the stock 302. Any block will take roller lifters by using a small base circle cam. EFI is hard to fit under a stock hood without a body lift but runs better when done right. Lots of choices and compromises. Good luck!

 

[ilovemaui]

If you are in Kauai, I am curious how much shipping is from NJ?

 

[Kauai72Bronco]

Shipping was free to the freight forwarder in CA...then $314 from there to Kauai. Not too bad.

 

[Kauai72Bronco]

So...ordered a SS Flexible dipstick from Duff as well as the Alt/PS swap brackets. I have new Hedman Headers from my 302 and the stock Holley carb. What other items will I need to swap in the 351? Anything I'm missing?