I'm looking at swapping a 351 in sometime here soon (wish it could be sooner rather than later, but with my finances....) and I would like to build the engine up a little BEFORE I install it. I'd like to get the horsepower near to 300, hopefully if I take it easy I won't detonate the M5OD (I can't do a tranny swap. Yet.) I've heard that my state (Michigan) is gonna start getting curious about what comes out of my tail pipe, so I don't want to just put in a carb motor, until I know more about what's going on. Seeing as I'd like to stay emissions legal. What course of action do you guys suggest to get my up there in power? I've seen lots of stuff, like heads, headers, cams, EFI intakes, computer mods, etc. But I want to know what will work best with what and still stay friendly with the pollution police. Thanks in advance.

 

300HP is easy with a 302, even easier with 49 more cubic inches! This will get you easily to 300-350.

Get an '84+ one piece rear main block. Eliminate problems. I'd use some high quality hypereutectic pistons, but I prefer forged. Stock rods and stock crank are more than adequate for 400hp+ let alone 300. Be sure to use ARP rod bolts, head bolts, and main bolts.

Use the highest quality bearings. This is not an option, as you motor rides on these. Don't skimp out to save ~$20.

You'll also need the accessory brackets, different motor mounts, and the other 351W swap stuff.

Piston wise you'd get ~9.1:1 with 64cc heads...the factory iron heads I am going to recommend I'd deck to ~ 60cc for a nice bump in compression. Close to 10:1.

I'd run a set of Ford factory GT-40 irons. They came on 93-95 Cobras and up to the '96 Explorer. The others are P style and need special headers. These flow very well with light port work and some bowl smoothing. Also Ford included Crane roller rockers on the 93-95 Cobras, those heads typically go for $400-500 used and the rockers $100.

Cam wise choose something mild. A 204/212 or a 208/216 ~.470 lift 114LSA is going to be best to work with the stock computer and still give you enough low end power to tow.

You will need more fuel. I'd get a Walbro 255lph inline and an adjustable regulator too. Obviously you will need 351W EFI rails. Intake wise, I'd skip the OE 351W intake, its pretty restrictive. Spring for the Edelbrock 351W EFI intake, much larger ports making more power.

Electronics...you are gonna need a 5.0/5.8 engine harness for the injectors, sensors, etc. The 351W has a firing order of 1-3-7-2-6-5-4-8 like the 5.0 HO. I'd also spring for the FMS MAF kit, this will make all of your mods work together better. Only problem is that kit is setup for the 1-5-4-2-6-3-7-8 firing order...but this is fixable by swapping injector wires between the 5 and 3 & 7 and 4...from what I have thought about it.

Exhaust wise, Hooker makes nice long tubes. A few people on here have them...I do, lexluthr69, and gamehunter I think also. They are nice with 1.5" primaries and 2.5" collectors...those should work nicely with those heads/cam/intake setup. Just run a single high flow cat off a y-pipe or dual cats into two or one muffler. Magnaflow makes a dual in/dual out muffler that has a built in X crossover! That will save a ton on costs...

That's really all I can think of...

 

Thanks for the (ton of) information, sounds like a good plan. Sure wish I could just go crazy with a carburated motor, save some cash, no such luck guess.

 

But want to keep same 5.0 engine in 87 F150
Very limited budget. Thought I'd just start with some headers. But I'll soon have to rebuild engine since it has 170k miles.
What headers will bolt up w/o any modifications & still give a good power boost?
Tx,
Rick

 

snadrat...You can go carb'd but I really have no idea what will be needed to make that switch. This is what I think of carbs... I just can't see myself going backwards in technology.

rickthefix...the only headers that bolt up with no extra work are direct replacement shorties. Shorties don't have the large power gains that full length headers have. Don't expect any "face-distorting thrust" from just that swap.

You'd need those shorty headers, high flow cat, and a good flowing cat back like a Magnaflow to get some power.

 

Can I live with the stock heads if I have to ($$$ issues.) Just get them milled and maybe try to do some of my own port work on them? I've played around w/ junk heads in the past, do you think I could handle this w/o screwing it up too bad?

 

Here are some head flow numbers I got today...

Here is what I cam up with...many of these are not in the 160cc area some are closer to 185cc but I got as close as I could.

.500 LIFT - 28" of H20

156/108 - Stock E7
185/129 - GT-40
196/139 - GT-40 P
204/144 - GT-40X
205/141 - Dart SR
219/151 - "Thumper E7"

237/172 - Brodix 5.0
243/185 - AFR165
245-251/170 - Edelbrock (intake flow based on valve sizing)
251/187 - Trick Flow Twisted Wedge

I could not find any data from Canfield, World Products, of the GT-40Y heads... for heads in this size range...must be a secret or something. But their heads are all almost 180cc+ heads which barely fit in this ~160cc range.

You can easily clean up the stock heads to flow far better. Those Thumber E7 heads flow pretty well for being $600. They have lots and lots of port work done to them though. I'd say with just gasket matching your stock heads you'd get around the flow of the GT-40 Iron flow.

 

Thanks for the quick reply. Now another one: What do you think of the Trick Flow EFI intake?

 

That TrickFlow EFI intake won't work with your truck unless you feel like making a custom thorttle and cruise cable.

I'd just go for the Edelbrock EFI 351W truck one. If you need more air flow (like if you ran awesome heads) you can port it as it comes apart. That is the intake I am going to go with when I go for a 392 down the road.

 

I just had my 302 rebuilt and I am pushing about 325. cost me 3800.00 gave or take that was new forge pistons, crane cam you can chose com or rv both will work i change my oem rockers to roller style, port and polished the heads and over sizes the valves balanced the entire engine. that was includes in the blue print. and i changed the exhaust sytem to a bassani from the headers back to the pipe out. that cost 1500.00 and the good thing about it all I still passed the smog test here in California.

 

Was that 1500 included in the 3800, or was that seperate?

 

how bought getting a complete 351 out of a 96 ford van at a wreckers with all the fule injection stuff there and wiring harness. I believe these engines have roller lifters which is good and to get more power just get a different intake and a mild cam maybe some headers and your in buisness.

 

Something to consider 5.8 351 blocks 94 and up have roller setups or are set up to install roller cams. That is a plus, however, you can make power without a roller cam. Do you have emmisons testing? If not then a carb motor would be easy to do if your on a budget. Efi is great, with that in mind if you have a well tuned carbed motor with a good aftermarket igniton it will perform fairly close and actually make more hp with less money invested to a certain point. They will fire up cold just like an efi if set up right. The last post had some points if you can find a complete efi engine with accessories that would be ideal. Good luck

 

Have looked at yard 351s lately. Van engine harness won't work in pickup. Harness connections changed around 96 also. Your original V-8 harness probably work. Low milage motors hard to come by since they don't make 'em anymore but have found some in the 70K up range though most over 100K. They are out there. Good luck.

 

the 1500.00 was separate from the cost of blue printing my engine. this is the price i paid for the complete hi flow/hi preformance exhaust. i would say that it was well worth the money i spent and every thing bolted right up an hung in all the factory hangers. not bad i would say for a do it yourself stainless exhaust system.