ventagemod67

hey guys.. I'm in the process of building a 347 out of a spare 289 block of mine. I need some ideas for head, cam, intake set ups that work well together. I have edlebrock performer cam, intake, and carb on my 289 now.. kinda want more power. I also have lt headers dual 3" pipe with maggies.

Thanks for any input

Starfury

Well, the 3" pipe is way oversized. 2-1/2" will do you fine up to like 400hp, iirc.

That said, here's my 331:
Original C6 casting 289 block, .030" over
Scat high-nodular cast crank, 3.25" stroke
Scat forged 5.4" H-beam rods, bushed for full-floating wrist pins, threaded for cap-screw rod bolts
Block clearanced for ARP cap-screw rod bolts
Align-bored mains with high strength main bolts and cheapo stud girdle
KB hypereutectic pistons with valve reliefs
Cut-to-fit plasma moly rings (required with pistons)
Trick Flow Twisted Wedge Street/Strip heads
Comp Cams cam-matched dual valve springs
Comp Cams Magnum 280H cam
Rhoads lifters
Crane 1.6 roller rockers
Weiand Stealth intake
Edelbrock 600CFM carb
Crappy Taiwanese headers
2-1/4" H-pipe duals
Twin Hushpower II mufflers

On paper (well, desktop dyno), it's good for ~355hp (optimistic). The torque curve is fairly broad and power is usable (although not fantastic) at about 1700 with the Rhoads lifters. Power really comes on at 3k and pulls hard until 6k+. Before I swapped out a set of slightly worked '68 heads, power would start to taper off at 5600.

67mustang302

AFR 165 heads, Crane 1.7rr hyd roller cam, Scat 5.7" I-beams with Mahle pistons and a 302 crank, Weiand 8124 intake, LT's ignition, carb, yadda yadda.

If you're starting a ground up 347 build, my choice would be some TEA heads(Twisted Wedges for instance, you could call them and ask what they think would work best for what you want) and a custom cam.

kalli

i agree with Tad, bit of too big a pipe... anyway, what's currentl;y holding you back is "edlebrock performer cam" if it's not the RPM model.

if I were to build a 347 for street, I'd go for TFS heads as well

ventagemod67

Thanks for the input guys. I originally did the large pipe for future plans of a 408. I have a 351 PI motor that I wanted to stroke, but figured out a 347 would be much easier and more qualified for the setup I want. As far as my current parts in my 289.. I've had the cam and intake since I've had the car and just used them for the time being. I for sure want to do aluminum heads and a roller cam, just wanted to know some good set ups. I would like the bottom end to be light weight so it'll spin to the moon.

A little additive.. forced induction vs. high compression

MBDiagMan

Actually given that he's using a 289 block, the Performer cam might serve to hold it together. The reason I say this is that due to the shorter cylinder wall on the 289 block, spinning a 347 to super high RPM would not be a good plan. I am getting things together to build a 347 and it might end up being built from a 289 block, but mine will be a low speed torque motor to pull around a heavy Galaxie. It will probably never see 4,000 RPM. High RPM with a 347 from a 289 block carries some risk.

BUT.... since I never thought anyone would ask, I'll outline my 289 and 347 engines:

I am currently cobbling together a 289 using a pretty decent engine that came out of my parts car. This will serve as something to allow me to cruise this Summer while I'm saving my pennies, gathering parts and putting together my 347. These engines will drag around a 64 Galaxie 500 that weighs about 3,700 pounds.

289

It is a five bolt 289 with not too much wear. It is a sort of recent rebuild with .030 over cylinders and .010 under journals. The cylinders mic less than .002" taper and the crankshaft mics perfect. So my shortblock consists of these parts with fresh rings and bearings. The valves were paper thin in the parts car heads and I managed to get a set of early 289 heads with new 351W valves, pocket ported, screw in studs and guide plates and all new valves for not much more than a set of new valves and a valve job would have cost.

For this cobble together engine I have a Comp 252H that I will use along with a set of roller rockers. Since I've got 'em, I'll use 'em. It will be topped with an old Edelbrock Performer 289 and a 600 Holley with Tri-Y headers.

347

I've gathered up some parts for the 347 including a set of 69CC heads with 2.02 and 1.60 valves and I previously pocket ported and gasket matched them. They will be used with the same Performer 289 since that's what I have and I'm building this engine for low and midrange torque anyway.

The 347 shortblock will be with flat top hypereutectic pistons (9.5 CR with the above heads,) and a cast crank. I haven't selected a cam yet, but it will be pretty mild, probably an XE 256H. I will use the roller rockers on this engine too.

Both of these engines will be trimmed to try and make them look stock. I have modified an original 289 air cleaner to fit over the DuraSpark and for added air flow. The engine and air cleaner will be painted and decaled like an original and the only thing that will look non stock without close examination in the engine compartment will be the headers, which being Tri Y will be a good period modification.


I hope no one minds my posting of stuff used on a Galaxie in a Mustang Forum. MOST Galaxies on the road have FE's of some sort, so there's no small block engine discussion on the Galaxie sites. The early, Small Block Ford Kings are on this forum, so this is where I go for my 289/347 engine discussion.

If it helps me to earn my Visitor pass to this forum, I've had 4 Mustangs in my life, two 66's, an 85 GT and my current 2006 Mustang GT.

ventagemod67

Oh and I'd like my hp between 400-450 n/a and 500-600 forced induction.. I've seen many 400-450 hp 347's so I know it's not out of reach

MBDiagMan

ventage,

WOW! That kind of horsepower level is reachable with a 347, but the only way to do it is at high RPM. Horsepower is NOT a measured value, it is a calculated value. Regardless of the horsepower figure of a particular engine configuration, the maximum torque is always ROUGHLY the same. To get the horsepower up, you have to move the torque peak to a higher RPM level. Again this is doable, but using a 289 block which provides less bottom cylinder/skirt support, it gets VERY risky.

Are you already committed to a 289 block? Have you already begun the machine work on the block? If the answer is no, find a 302 block for the project. A house is no stronger than its foundation and the block is the foundation of the house you are about to build.

Sounds like a great project! Build it on a good foundation. A few extra hundred bucks at this stage of your project might very well keep it from turning into a hunk of junk iron at one point in the future.

Keep us posted and enjoy the project.

BTW, I forgot to comment earlier on exhaust size. On an engine of this size 3" pipe is too big. The gas speed in that pipe will be very low. This will cause two things, it will probably pop and snap and sound bad, plus it will actually decrease the efficiency of the exhaust system due to less momentum to keep the gases flowing.

Starfury

Not out of reach, but it's probably the most I'd expect out of one. You'd definitely need a roller block, higher compression, and a very good tune. I'd also start to worry about block integrity at that point. Main girdles and lifter valley supports are good ideas above 450hp.

Why not stroke the 351W? You could run 400-500hp all day long with a 383 and it would be much more streetable than a 347 build.

Starfury

MB, there are a lot of people that claim 289 blocks have shorter skirts than 302 blocks. The only person I've ever talked to that measured them side by side mic'd them as being identical.

Personally, I'd start with a roller 5.0 block just to make life easier with cam selection, but that has nothing to do with cylinder skirt length.