I have a 1994 F150 5L and was wondering if replacing the heads and intake from a 5.8L motor would be benificial for time and effort involved. Now I have 205 H.P. and want to increase it.

 

is it a stock 5.0? if you have a stock motor w/ no mods you don't have 205 HP. you have 185 HP. get the exhaust and intake done . both will get you about a 1% increase . i don't know if the heads will work . never tried it . ya might need chris to answer that one . he may know . or others here may know .

 

If you put stock 351 heads on the 302 you wouldn't gain too much. If you were to port and polish them and put in larger valves you could get a serious power increase.

-Jon

 

To Macgyver:

The 1994 "N" 5 L , EFI is listed as 205@4000 Net Horsepower@RPM and 275@3000 Torque

 

Someone please correct me if I'm wrong, but....

From what I understand, the heads on a 351 are just as restrictive as the heads on a 302. And I'm not so sure that you could put a 351 intake manifold onto a 302 engine. My advice to you is-- don't do it! Since you have 205 hp stock, I'm assuming you have the mass air setup, which is good for internal engine mods. Just to remind you, the stock hp rating for a 351 is 210, so there really isn't much if anything to be gained by a head/intake swap. The 351 does have about 40 ft/lb tq on the 302, but I'm pretty sure we have the longer stroke to thank for that, not the heads or the intake. All in all, I think you'll run into more trouble just trying to install everything correctly than its worth. And to be quite honest, I really don't think you have anything to gain by doing that swap except headaches. Look into getting your heads ported/polished, or better yet, Edelbrock has some aluminum cylinder heads made for your truck that are good for at least 30 hp. They also have intake manifolds, headers, etc. There are countless parts made for the 5.0L engine that give results, so there's no reason to borrow stock parts from a 351 and cross your fingers that all the effort was good for at least a couple hp.

 

Yeah, our heads suck for air flow on these 302's. I have talked to our "HP" buddy and he recommends Trick Flow Twist Wedge with 2" intake and 1.6" exhaust. My buddies '29 Ford with the 302 in it will probably go that way as well when we end up finishing it. As for intakes, you can go with aftermarket (Edelbrock, etc.) or maybe even look into whether you can find one off of an older mustang that had the High Output motor. Oh, if you get the Trick Flow's, have them port & polish as well before they ship. You can also port & polish your intake and intake pelnum off of the truck, that should flow better than stock if you didn't want to change that.

Have Fun & Keep on Truckin'
Dean

 

Go with the Edelbrock setup...........it's one of the best things you could do!

The most bang for the buck.

 

Someone else may know w/ certainty but I'm 95% sure that 351 wears the same heads as the 302: E7TE castings. Intake upper is almost identical between the 351 and 302, both suck for HP over 4000rpm. Lower is different because the 351 is a taller block so the distance is wider at the top of the "V" so you can't even put a 351 manifold on a 302 engine. The truck engine has almost the same HP because the heads and intake suck for HP and it limits the engines potential, no matter how many cubic inches are trying to suck in air. It has more torque simply because of cubic inches.

I had a 95 EFI 302 and swapped on box stock TFS TW heads. I personally would NOT port these heads for a truck unless you plan to put a 4:10 gear or more and rev it to over 6000rpm. Without changing anything on my previous truck the heads gave an awesome kick in the pants, probably 30+rwhp. Had I swapped the intake, I could have seen a total of greater than 70+rwhp. If I were to do it again, I would get a pair of AFR 165 heads and the Edelbrock truck intake IF YOU ARE LOOKING FOR NATURALLY ASPIRATED power. Me, I'm tired of watching my fuel gauge plummet ( current truck has custom cam, full exhaust, lightly ported stock heads, ebock efi intake, big tb, mam, ram air etc). I get 11.7 - 12.2 mpg and was getting 13.5 to 14.5 before the mods (difference being summer/winter gas). Granted I drive it like I stole it but that still sucks.. If your looking for $/HP, go w/ a Vortech A trim. If your looking for naturally aspirated power, get some box stock Ebock Performer/TFS/AFR165 heads and enjoy and if you can spring for the Ebock intake, even better.

 

a 351w has a wider deck than the 302, so teh manifolds will not fit.

 

For the most part, this is correct.

Take care,
-Chris