i am building my first motor right now.it is a 90 model 302 bored .060 with speed pro coated pistons and a 286 duration cam, weiend 4bbl intake and an edelbrock 650 carb, accel tfi distributor which i am going to sell and get my an hei ignition crank turned .010 heads redone long tubes i am putting it in a 71 short wheel base f100 i have a c5,c6 and an fmx i want a c4 but if i cannot find one i will rebuild the fmx. i am putting some 3.50 gears into my 9 inch rear end. i think it will be a stout motor how about everyone else. how much power do you think that will produce

 

I would use the C6 it's a stringer transmission that he c4, c5, or fmx. It can be rebuilt for next to nothing and will take whatever you through at it.

 

OK, first of all you surly don't have to spend 1400 dollars on AFR heads to get 350 HP out of a 351. If you go with AFR heads, especially the 185cc version (which everyone knows are by far the best bolt on head available) you are looking at way over 400HP out of the box with a properly matched cam. These heads flow ALOT and the 185's are more orientated for racing applications or if maximum HP is desired, and if you are concerned at all about gas, these probably arn't the ticket. BIG, powerfull, naturally asperated engines just don't meet the fuel standards that stock engines will. If you pick up a pair of ported and decked (for extra compression) GT40 iron heads (cheap as dirt), roller rockers, XE or custom ground ROLLER cam (this piece plays a major factor on gas mileage), 2.5-3" dual exhuast, long tube headers, and an edelbrock EFI truck intake, you will probably be looking at 350HP and still be able to get 10mpg or better. However, in order to save headackes and major $$$ in the long run, go with the mass air conversion from FMS or Pro-M. Or else you will need to chase down an engine dyno analzyer every time you do a significant engine mod. And that isn't exactly cheap either. The setup above will probably produce over 400 ft/lbs of torque, probably wont be any too dissapointing.

If your looking for a bulletproof shortblock, and price is no issue, Jegs has an FMS sportsman shortblock 5.8 for around $2300. Also, I believe the stock lightning shortblocks are still available from certain sources since I just saw one here not to long ago. These are built about as good as it gets too. You should get way over 100k of commute to work reliability from either of these setups with a 400HP+ engine.

As for the transmition, I would think you could stick with the one you have, at least untill it breaks. I've talked to people who run them in their mud trucks with 400HP 351's with no problems. Definately not the ideal setup, and although it is much better the ZF isn't exactly the best choice either. In OD, these trans try to literally pull apart from itself since the gears are working against each other. It is like turning your trans around backwards and running your engine off the output shaft. The OD gear trys to rip open the trans case, which is the reason it is generally bad to do alot of towing in OD.

 

c6 takes too much power to turn but that may not matter because i found somebody with a 76 mustang and a manual tranny probably a 4 speed but not sure , they might trade me it for my truck i will put my motor in the stang ,oh yeah

 

10mpg or less? Ouch.

 

A C4 is a great transmission, you don't need a C6, they require more power to drive, and they're heavier. FMX is junk compared to a C4, stick with that one. I like what gamehunter said, but don't forget about World's Windsor Jr. heads. 1.94/1.60 valves in a 58 cc chamber w/ 7/16" rocker studs and 180 cc hi-velocity intake runners for $800/pair, assembled. I have a pair atop my Motorsport block now, and I love them. Keep in mind that most of the airflow restriction in an engine is in the cylinder heads, so investing in a good set will dictate the performance potential of the engine, and the quality of the finish will dictate how reliable it is. For instance, a set of junkyard heads may be ported to flow like crazy, but if they don't have a good deck surface, they won't seal for long, if at all, and will eat up head gaskets like no other. The best thing to do is to read everything you can about different cylinder head designs, and learn about what makes some better than others, and even if you go with a set of used heads, you'll have a serious heads up when you go to the machine shop!

Building an engine is just like building a project car: start out with a vision, and work directly towards it. It's so much better to spend a little more money in the building process and get what you want than to spend money doing things in stages, bolting parts on every other weekend! TK

oh, and if you want to run a 3.50 ratio with a C4 and V8 in front, don't be afraid of 10 MPG, in fact, be prepared for much worse!

 

I would be running a 5 speed with overdrive. 10mpg stinks....no way I could get like 12-14ish?

 

Hey mustanggt221,
It's been a while since I was a net surfer. I don't know if ya remember me or not I had the (still do) the black eddie bauer, then I purchased another truck and had the 351 rebuilt had a heck of a time with the rebuilder, hey it finally worked out. I see you haven't had someone smash into your new truck. Noticed you are dreaming about a 351 now. Why not keep the 302, if it is in good shape you could bolt on some afr heads ad a cam all in a weekend or so and have a lot more fun than waiting on another motor to be built. Lot of room for a cam selection since you have the 5 speed you can make it lumpy or at least as radical as the computer would allow. Oh well good luck with whatever you decide.
jtaylor

 

Jtaylor brings up a good point. But you must first ask yourself if you are the type that likes instant gratification, or are you more willing to wait for something much better? I have heard of plent a mustang owner who seriously hopps up their 5.0's with high flow heads/camshafts with a good amount of miles like you've got. But I personally wouldn't expect it to last more than another 15-20k with that kind of power on a 90k mile truck engine.

The 302's are amazingly cheaper than the 351 to build. However, torque is not cheap and that is what a lifted truck needs so you don't have to rev out to 4k at every stop light just to get the truck out of its own way.

As for gas mileage, 12-14 is not unreasonable. However, that generally means staying away from cams with less than 112lsa and probably not a whole lot more than 220 degrees @.050 . But, for 350HP out of a 351, you really don't need more duration. A mild performance cam, good flowing heads, and the basic bolt ons to help your engine breath is good enough for some serious torque and your gas mileage may not go down at all or just a little bit compared to a stock 351. If your talking highway MPG, no problem. 12-14 in town might be a bit optimistic.

 

I only mentioned the 302 with afr heads as many have read in a mm&ff magazine they took a stock 5.0 ho longblock added the afr heads with 1.7:1 rockers albeit with performerrpm and carb they got somewhere close to 400hp even if the dyno were off some that is impressive. They did the same with a stock efi and came close to around 350hp with that fuel injected setup I believe if not a little more. Hey those cams are cheap, heads + rockers a little money but easy bolt ons. While the higher lift would raise the peak hp and tQ I would say it should do fine in the old truck, then it should perform near stock using a ford cam, they had a stock roller but take off a couple hp for the plain hydraulic flat tappet that your truck probably uses and it still easy hp. Besides when it is time to 4wheel it, 4low will take care of getting the engine to the torque side of the engine. Kind of sucks when you get too many perspectives, kind of brings you back to the start scratching your head huh. Again good luck

 

Yep, I remember ya. The only thing about the 5.0 I hate is the lack of low end power because of it's short stroke. The 5.8 has a much longer stroke and in general is a better truck motor. The 5.0 is a great motor, but probably serves better in a mustang. I get 12-14 hwy with this truck and about 10-11 city. I wouldn't like that to get any worse if I can help it. I need power down low because on this engine I have to get the RPMs up to get any power and that's what kills my gas mileage. I also tow 2500-3500lbs often and would love to get some extra power for that. I'm going to need it with my 6" and 35's. I would have just hopped up my 5.0 if I could get the low end power out of it, but the 5.8 to me seems like the way to go. Theres just so many options out there. I'm not new to these trucks, but I'm new to engine building, I know what parts are what and have basic knowledge but as to which kind of parts to buy I have no clue.

 

I get what your saying. If all you want is torque then I would think it would be fairly easy task. Get a 351w block scat 393 crank $300, stock 351 rods with arp bolts, stock 302 hypernetic style flat top pistons again not too expensive, and maybe some reworked stock heads I believe the later carbed efi heads on 351 where the 302 design anyways so why not save a little and have yours reworked add a rv/towing or something designed for torque cam and you should have some nice low end torque. I would imagine you could go with the iron gt-40 heads off the lightning and they would go well with the 393 setup for torque since you don't want peak hp. Are you gonna keep the efi? I think all you have to do is change the lower to 351 and the upper intake will bolt down no problems, but then you have to factor in the chip for the change/custom and I am not sure if the distributor will work from your 302, I believe they use different ones. I noticed that in the article where they tested the afr heads they also tested the stock e7te heads and the torque was actually the same even though the afr made close to 400hp even better the stock heads made the torque 700rpm lower, so if your shooting for torque you can keep the heads pretty conservative. Good luck Mr. Moderator (how did you end doing that? Do you have to look at all the posts for improper wording/messages?)

 

Man what are the odds of this on ebay they list a few rebuilt heads with larger valves for $250 I believe they are the 70 style so that is even better. Also found these low mile gt40 heads off a crate motor might be something worth checking out
http://cgi.ebay.com/ebaymotors/ws/eB...category=33617
Later

 

I wouldn't touch an E7TE head (even ported) with a 10 foot pole if I was building a 393. For that much cubes, the stock heads will create a major bottleneck. A 393 is just about big block size, so you need something much better if you expect it to breath past 3500rpm. The GT40 iron heads would be a much better platform to start with. For going all out performance, this is were the AFR's really shine.

 

Hey mustanggt221
Here is something else to think about, on ebay you can get a complete hawk stroker kit for $1175 or so. What makes it better is it uses a 6.2 rod instead of the stock ford which is 5.9**. So not only do you get a stroker you get a long rod stroker which equals even more torque due to the rod ratio. They list a 426 crank as well for $279 new, as well as a 393/408/418using the 6.2 rod. Can you imagine telling someone you have a 426, they would scratch their head and tell all their buddies that you don't know what your talking about, especially if you say it was a 426 small block. I would say ah to dream but if someone was gonna stroke their engine anyway it would be very realistic to do it. However getting a head to breathe with that stroke thats another story. Just a thought