Hey guys I have a confirmed low mileage 1982 351 Windsor. It has less than 60,000 miles and came from my grandmas LTD. Now this engine only has about 140hp which is really quite poor. Im a starving student on a extremely tight budget trying to put together an engine. What I would like to do is swap on a set of older Windsor heads or newer GT-40's. This would bring the compression up and while I do this I will swap in a XE-268 cam for a bit of sound and power. I plan to keep the shortblock stock until I have the change to replace. In doing this will I have piston to valve clearance issues on the stock 1982 pistons? Of course there will be a set of headers and a 4bbl carb.

 

I'd suggest the XE262H, that'll deliver a little broader powerband and a solid 300hp without touching the bottom end.. which doesn't need to be touched anyway.

 

A set of 69 heads for a 351w can be found for $50 on ebay. They will not out HP a set of aftermarket heads but they are cheap.

 

Well I have deceided to keep the heads stock. For now I just need a motor. With the pedestal mounted rockers and stock springs how large of a cam can I run. Im thinkin the comp cam high energy 268H. I would just like to spruce it up a bit for the temporary time being. I guess my question is how much work is it to swap a slightly larger cam into a virtually stock shortblock and what all will have to be changed.

 

Both the cams mentioned here are a TON bigger than stock and will essentially double the engines output when coupled with a carb, intake, and exhaust. The cams also produce about as much lift as the stock springs can handle, no other internal parts need to be changed.

 

Much appreciated for all the help. Does anybody by chance know the valve spring specs on the 351W. It always states to change the valve springs but I really dont wanna sink all this time into it when it will be getting changed in a few years. XE262H seems like a good all around cam. Will stock springs be compatible? I have intentions of just dropping in the cam and new timing chain. 4bbl intake and headers, and calling it a day. I want to make sure I wont run into issues tho. Will valve spring bind or float be an issue with stock valve springs?

 

No stock springs are fine, they produce about 90-100lbs closed and 190-200lbs open and can handle about 0.520" lift.

 

Some things to think about..

1) Pull carb off....hoses etc etc
2) Pull hoses off of intake and pull intake off
3) Scrap off loose gasket material
4) Take push rods out. Wouldn't hurt to let them soak in gas.
5) Pull dizzy. Helpful to mark wires.
6) raise lifters a little
7) Unbolt stuff from front end of engine so that you can slide old cam out

Hope you already washed and dried your new cam at this point

8) You need lube. Put it on the cam as you put it in the engine. Be careful not to knick anything at this point.
9) Bolt front of engine back up
9.5) Put Dizzy back in
10) Take your rocker arms off.
11) Lube your cleaned push rods and put them back in
12) Set your lash on your rocker arms
13) Put a socket on the front of your engine and turn slowly. If a valve hits your piston, it is not a good thing.
14) Assuming everything is ok. Put gasket for intake back on and trim to bore if you can.
15) TQ the bolts in the correct order and tightness
16) Put carb back on with gasket
17) Set the timing and degree your new cam
18) Don't forget to take socket off the front of the engine or you might ruin your engine.

I'm sure others might chime in.


It is a lot of work. To pull the cam be sure there is enough room infront of the engine, otherwise you will have to pull the engine to put the cam in----not fun.


I'll be at the same point you are in a couple of months. I'll be putting in a new cam and new heads. The cam cost wise is no big deal mine is $119. The heads are another story---$1500 for the ones I want. Funny, the heads IMHO are easy to put on and the cam is a PITA to put in. I wish I had put the cam in while I had the engine out, it would have been a lot easier.

 

I too think the stock springs will be ok. The only place where they might not be ok would be when you really rev the engine. You might get valve float then.

Don't rev the engine after you put the new cam in. Keep the rpms low for a while. Let the engine settle into it new cam.

BTW The old springs will actually 'break in' the old cam better. I've heard of guys putting extra stiff double springs in only to have a flattened cam because they didn't break it in the right way.

 

Looks like im gunna need a degree wheel. Could I possibly get away by just installing the cam straight up? I also plan to keep the stock pedestal rockers. Will they be acceptable for a higher lift cam? I apoligize for the questions but I want to make sure things are right. And one final question. This motor has a duraspark ignition but I no longer have the car. It has the distributer on it. What all will I need to get the motor running again?

 

Degreeing the cam is really just to verify that you got what it says on the box.. unless you are going to retart or advance it of course. A dial gauge and degree wheel are needed for this but they can be had pretty cheap and I have even seen a printout degree wheel online before, just glue it on a piece of cardboard or something. Stock rockers are fine as well, that's what is on my 5.0 right now. What vehicle is this motor going in? Does it have an ignition system?

 

Is going it a 65 M-100. I currently have a pertronix ignitor on the 302 that is in there now replacing the points. I know that the duraspark distributor needs a ignition module to work properly. Would a upgraded one such as a msd unit be a sizeable improvment? I do have a dial gauge so im good on that front in terms of degreeing. One other question is regards to setting the lash on rocker arms. Isnt it non adjustable? Just bolt it down and go?

 

IMO the only feature of the aftermarket ignition systems that are better than the stock setup is the selectable rev limiters, the stock ignition is otherwise more than capable of running a motor so unless you need a rev limiter it won't deliver any better performance.

The rockers are non adjustable so yes you just torque them to spec and forget about it unless the heads or block have been machined, in which case some shims may be needed.