351w swap

[OUTPLAYN]

I have a 91 F150 w/ 351w...what can I use off the truck....what else do i need for the swap?

[LX5liter]

I've never done the 351w swap, but I'll state the obvious.
You can use the long block and the lower intake. Keep the 351 flywheel and harmonic balancer as well, as these will be the 28oz matched set.

The things you will need: oil pan, headers, motor mounts, different brake booster (possibly), and there is accessory drive considerations as well. These are some part #'s from the technical reference handbook that should help with the accessory drive; M-8510-C351 (crank pulley spacer, FRPP #) and M-8511-B351 ( FRPP# for mounting plate to use the standard power steering pump and A/C compressor).
There is probably a whole slew of stuff I am missing here that someone who has actually done the swap can fill you in on, but this should give you a rough idea as to what's involved.

[OUTPLAYN]

Are the heads swapable? If ya have hads on a 5.0.....can ya put them on a 351w?

[82 GT]

The 5.0 heads will work bolt on but they are not a direct bolt on.
First, the water passages are different which requires some machine work and also the bolts are different sizes between the two heads.
Most people put 351 heads on 302's not vise verse.
As far as engine swap goes: You won't need a different brake booster but you will need the other stuff LX5liter mentioned as well as headers.
Is this going to be EFI or a carb motor?

[OUTPLAYN]

I want to go efi..I hear the computer works just fine..headers..they just have to fit different..in the bay?

[82 GT]

You need either shorty headers or long tube headers that are made for a 351w in a fox body.
The difference between 302 & 351 headers is the way the exhaust tubes are routed. The 302 headers will not clear the steering shaft. The 351 headers are routed tighter towards the engine to get that clearance. (Believe me...I found out the hard way))

[82 GT]

Another thing you may want to think about is hood clearance.
The 351 has a taller deck height. You might need a cowl hood. When I had my stock hood on my '82 I had the hole cut out for the factory scoop. I don't know if it would have fit or not without that hole. Now I have a fiberglass hood with a 2.5in cowl and that works ok.
I would also immediately get subframe connectors if you haven't already.

[RdRunnr]

You will need 351 engine mounts. They make mounts that will lower the engine 1/2" lower to give you greater hood clearance.

[BilLster]

Little thigs like motor mounts some oil pans fit , other over looked things are fan electric , i dont think the stock will fit in m shroud with out dropping the motor , which water pump will you use the 302 or 351 which rotation depends on what acessories you plan to run . jeff chambers has a good diagram on his web page about this. i whent 351 dropped the power steering and smog pump. fuel rails distributor , i made my own box style intake
and ported out a truck lower (i'm trying to convince myself to by a trick flow or victor lower but cant justify the price for the perfotrmance . boost evens all. Rad will you get a bigger one ?
the main problems occour if one motors auto and ones stick flywheels and such you want to upgrade the tranny some.

what else did i learn the hard way. headers oil pan upper manifold rad fan oh yeah fuel pump upgrade and injectors the truck 351 comes with 19 also but will a free flowing exchaust and manifold upper you will easily tax them also the heads are the same the ony mod problems are with pre 86 302's and 351 heads the water passages have always been the same except for clevland heads. which you wont need to be concerned about.


keep everthing you never know what you might need.

i still want another set of 69-70 351 w heads.

good luck. what mods are on the car now ???

[6T9PONY]

Originally posted by BilLster
i still want another set of 69-70 351 w heads.

Why? They suck. The valves are tiny.

[82 GT]

Originally posted by 6T9PONY
Why? They suck. The valves are tiny.

That's the first time I EVER heard a statement like that about 69-70 Windsor heads! I could be mistaken, but aren't they the best 351w heads made? Small valve sizes can always be replaced with larger ones.
Besides the Cleveland and Boss heads, what year Windsor heads are the best in your opinion......post '74-up smog heads?
Please fill me in here. Like I said before, I could be mistaken but I don't believe I am.

[RPM427]

Wil lthe drop down mounts fit my 302? I want to install 1 inch intake spacer without getting a new hood.

[82 GT]

Originally posted by RPM427
Wil lthe drop down mounts fit my 302? I want to install 1 inch intake spacer without getting a new hood.

I'm not 100% positive, but I am pretty sure they will fit.

[6T9PONY]

Originally posted by 82 GT
That's the first time I EVER heard a statement like that about 69-70 Windsor heads! I could be mistaken, but aren't they the best 351w heads made? Small valve sizes can always be replaced with larger ones.
Besides the Cleveland and Boss heads, what year Windsor heads are the best in your opinion......post '74-up smog heads?
Please fill me in here. Like I said before, I could be mistaken but I don't believe I am.

'69-'70 heads are definitely the best STOCK 351W heads ever made, but they still suck. Rather badly. 1.84/1.54 valves.....no good. There are probably some damn fast 351Ws with stock/semi-stock heads, but to easily take advantage of the rest of the engines potential you need aftermarket heads. Just offering my humble opinion.