I'm rebuilding a 302 in a 1985 ford truck. I upgraded to forged pistons and added a performance cam and lifter kit. I only have a two barrel carb. I was told by summit racing I'm going to starve the engine at high rpm until I upgrade to a four barrel carb.

I will eventually upgrade heads, intake manifold and install a four barrel carb, but cannot afford to do it all at once. If I buy a performance intake manifold/carb combo am I going to be ok for a few years with factory heads?

I am also converting to long tube headers. So, I will have a better cam/lifters, better flow into the engine and out of the engine. I realize this is not a massive improvement, but I want to make sure my factory heads are going to be ok.

Also, will all these changes cause me to need to have my computer reprogrammed?

Thanks

 

Not sure exactly what you want to do with this engine, but with the changes you have
already made you do need a 4bbl carb and a good two plane intake like an Edelbrock
performer. Your factory heads will work with this but to really make power you need to
upgrade the heads and also the exhaust. I don't think you will have any problems with
a computer since yours is a carburated engine.

 

What cam did you go with? What pistons? Since money is an issue you can port the heads while it's apart. Intake and carb and not a big deal, do it in a couple months when you have the money saved.

If you're willing to do some searching you can probably find a factory iron 4v intake for peanuts (I've scrapped tens of them, would have given them away if anyone wanted one) and you can probably pick up a Holley 600 CFM 4160 for about $50, throw a $40 kit at it and you're golden for $100 or less on carb and intake. Or wait and get new parts later on.

 

I just want to make provisions for the future when my son is older. I figure if I rebuild with forged pistons and a decent cam (I'm getting a 268H cam/lifter kit from summit racing) the base engine will be ok for anything we want to do down the road.

I don't see us doing any supercharging or nitro or anything. I figure some good heads, intake and carb. If I have to do the intake and carb now I will. I am putting flowtech long tube headers and flowmaster 40s on it.

If i wait and do the heads down the road am I going to have a problem with finding heads that will mate up with the intake manifold I get now? I was looking at summit racing at an edelbrock performer dual plane intake and a 600cfm holley carb.

Basically, right now I just need to rebuild the engine, but it would be nice to make provisions for the future so we can add some decent HP down the road without being faced with a total rebuild. Any suggestions would be appreciated.

 

If I were you I would probably make a few trips to a local swap meet or something to look for your carb/intake before buying it new. I just recently bought a Holley 780 double pumper for my Torino for somewhere around 100 bucks, and it's a lot more than that new.

I noticed your location is in Ohio, depending on how close you are there is going to be a huge swap meet at the Expo Center in Louisville, KY later on this month. Probably find anything you can imagine there.

Kyana Swap Meet in Louisville, KY

 

Also with forged pistons, make sure the machine shop bores the motor accordingly.

 

My personal feelings are to wait until later for the manifold and carb and that you're being
told things by salesmen wanting your money.

I'm gonna guess you have a Motorcraft 2150 on there right now.

To calculate the size carb you need, take the engine's cubic inch size and multiply by the
maximum expected RPM, divide that by 3456.

So, for example:

302 x 6000 / 3456 = 524 CFM

The 2150 is rated I believe at 385 CFM which is good to about 4,500 RPM.

The carb doesn't care what cam or pistons or heads are installed, its job is to provide a
fuel + air mixture to the combustion chambers - how much is needed and at what
velocity, that's all a carb cares about.

What you do is dependent on the intended usage of the engine & vehicle - street, drag
strip, oval track, mud pits, gravel hauler, etc.

 

The truck will only be driven about 5,000 miles a year, if that. I will use it from time to time for towing fairly light loads. I would like to see a little more horsepower. I'm putting headers and flowmaster 40s on it mainly for the sound. The only racing I'll do is out of the driveway when my wife pisses me off.

In a couple years my son wants to put Edelbrock performer heads, Edelbrock intake manifold and a Holley 4 barrel carb. It will be his toy to do whatever with then. I'd like to know the engine can accomodate his future adders. For example, I thought forged heads and a performance cam would be wise. However, the truck has to run now. If i have to put a carb on it I will. I'm currently looking to see what a local salvage lot has as well as craigslist.

I would just hate to see a rebuilt engine have to be rebuilt again in a couple years to accommodate my son's adders.

 

If you haven't bought the forged pistons yet, I wouldn't. If you were going to supercharge or use nitrous it may be different, but using a forged piston in your application is just overkill and a waste of money. Also you will not like the noise the engine makes on cold start-up. The engine is going to knock some in the morning till it warms up with forged pistons.

I would go with cast pistons, or if you want to upgrade from that, the hyperteutic pistons, which are stronger, but don't need the large clearance the forged ones do, so they are not as noisy. I would then use moly rings on the pistons.

I would use the cam of your choice, but sticking a cam in a Ford engine is not as simple as it sounds. The Ford heads have a non-adjustable valve lash system, so you need to add some sort of adjustment for the heads, and that costs money. On these later type heads, you can add a little bit of shim under the rocker sled, but it's a fiddly way to do it. Problem is converting the heads to make the valves adjustable cost a lot of money, and that's why a lot of people just buy new heads. If you compare the shop work to redo the Ford heads, and then add in the money to make the valve train adjustable, you are at the same amount of money for a new set of cast iron aftermarket heads with larger valves, adjustable valve train, larger ports, etc.

If you want this to be a nice rebuilt engine that will be reliable with a little bit more power, I would go through the engine but leave it stock, add the headers and the intake and a small 600 cfm carb, and you will have a noticeable difference in power. Then later on I would think about a cam/head package to upgrade the engine further. You never know, the 302 has it's limitations and you might want to go to a 351w later on down the road.

 

These are two contradictory statements....

For towing & hauling, you need low-end torque, not high-RPM horsepower. I use my truck
for hauling dead trees (firewood) from the Colorado mountains down to the lower
elevations and it rarely sees anything over 3,000 RPM.

I have Tim Meyer's hypereutectic pistons, what is generically known as a RV cam,
straight-up timing set, dual-plane intake manifold & long-tube headers and a few other
things to help give me power on the low end in my 400. This is a decidedly &
intentionally different configuration than a high-RPM screamer.

Teenage kids are all about horsepower & chrome & showing off in front of their friends,
this is totally contradictory to to large, heavy, brick-shaped trucks IMHO but to each
their own. I like the idea of a 351W but do your homework here, you might talk with
some local performance engine builders....

 

You will be fine with the 2 barrel. You won't make the power at higher RPMs but how often do you see that? Just don't overcam the pickup and you will be fine.

As for Forged vs Hyper...I have both but for this pickup I would go with Hyper. If you already have forged, no worries they work fine, just a little more noise is all. If you are running stock rods and rod bolts they will fail long before the cast pistons will. At the minimum please purchase good rod bolts and have the rods resized! I have ventilated 2 blocks before I learned my lesson.

Kenny

 

I was told by a guy at summit that the cam/lifter kit he was selling me was just swap it out and go and no modifications were necessary. If that is not the case maybe I should leave it stock.

 

If it has the same base circle as the stock Ford cam, that is true and it would drop in. I would call them again and ask to make sure this is the case, and there will be no valve adjustment necessary. When you get the stock heads redone, the guy doing the work is supposed to compensate for grinding the valves also (hopefully) so it all works out. When they do work on the heads, this changes the height the valves sit in the head, so they have to do something about that.

 

Just FYI, me 351w is an old block with the 2 piece rear main seal. I put an edelbrock "RV" cam in with some d0oe heads on and just reused stock pushrods. Valve seats failed 5-10k miles later. I scored some gt40's from a 302. drilled them out to accept my 1/2" headbolts, bolted them on with the stock pushrods and they have been working fine for 1 year+

 

"valve seats failed 5-10k miles", that's what happens when using older 351W heads with
todays fuel and non hardened valve seats. They are not as good a bargain as they seem
to be.