[89LXHatch]

Alright, so here’s my problem… I’m 19 and in college and looking to build a motor for an affordable price that’s dependable but still able to dish out some pain to the rice burners. Currently I’m running an 89 LX with a stock bottom end 302HO. It already had under drive pulleys on it when I got it, and I have added BBK equal length shorty headers since. A world-class t5 is sitting behind the motor and for exhaust I’ve got an off-road H pipe, 2 chamber Flowmasters and 2 ½” pipes, no cats. Over last winter I got the rear rebuilt and had 3.73’s put in and 5-lug conversion all around. It moves pretty good and I’m happy with it, but at 142,000 my rings are about shot and my valve guide seals are shot, along with needing a new oil pump.

I’ve run into two deals and have jumped on them both, but know I don’t know which route to take. Option 1 would be to rebuild a 302, now it isn’t a roller motor, it’s a 69 block, but all the machine work is already done on it, including being bored 0.030 over. I’ll need a set of 0.030 over pistons, rings and a flat tappet hydraulic cam/lifter set to finish it.

The other option is to build a 347. I already have the 347 crank, it’s currently in the 69’ 302 block, but I’m just not sure if I want to stick with putting a 302 crank back in it since I have a spare. The downside to this option is I would need to buy rods, pistons, a 28oz flywheel, balancer, and the rotating assembly balanced. I’m also aware of the hard rod angle. How hard can you crank a 347? How long would a 347 last given the hard rod angle?

Parts I currently have installed/ to be installed:

GT40 iron heads (Off of 96’ Ford Explorer)
GT40 upper and lower intake (Off of 96’ Ford Explorer)
65mm throttle body (Off of 96’ Ford Explorer)
BBK Equal Length Shorty Headers
Off-road H Pipe
2 Chamber American Thunder Flowmaster CAT-back
Under Drive Pulleys
Ford Taurus Electric Fan
Stock items: MAF Sensor, 19lb injectors, fuel pump, ignition system

I’ve heard the 347 is an internally weak motor because of the wrist pin location and rod angle. I was also told to just go with a 351W instead of wasting the money on the stroker motor. I am looking to make some power, but I’ve also heard that I could build a nasty 302 and put a 50 shot on it and it’s just as powerful as a 347.

Since I don’t know all the in’s and out’s I’m just looking for some advice as to what would be more sensible. Again, I’m not looking to spend a fortune, as most of these parts have come from the junkyard, that’s why I’m building the 69’ block as all the machine work is already done. Also any estimates on power of the two given the same parts that I have for both builds? What size cam should I go with for street; I do want something that has a little rumble to it, was thinking something similar to the B303 specs; I shift at 5500 when I’m leaving the rice behind. If I use my 89’ crank in the 69’ block, do I have to keep my balancer and 50oz flywheel together with it?

Btw is the 302HO crank steel?

[EagleAutosports]

The 1969 block is a good choice, it has more nickle and is stronger than the later blocks.

The 302 H.O. crank is cast steel.

The newer 347 kits have been reengineered so today's 347's can live longer than the early versions. The rod angle is still true, but it's not that bad.

The thing about the 347 crank you have is, even if you get the 5.400 rods and pistons, the crank would have to go with the rods and pistons to be balanced as well, everything needs to be done together. Once done, you shouldn't have a problem turning it hard.

The P heads are ok, the Explorer intake is also ok, the 65mm throttle body might be a little limiting on a 347 though. There's many better choices for a 347 than the B cam, it's ancient and the newer cams will make better power.

If you use the 1989 crank, you'll need a 50 ounce balancer and flywheel.

[mmb617]

Nice post, you've obviously put a lot of thought into this project. Here's a few things that come to my mind.

If you're like most of us the budget is probably one of the most important factors in deciding which way to go. From what I can see it doesn't look like it would cost you too much more to go with a 347 instead of a 306. If you consider the cost of adding spray to the 306 to bring it's power up the the level of the 347, the total costs are probably about the same. With this being the case I would take the extra cubes every time.

You could have the same power from the 347 N/A as the 306 on spray, and still have the option of adding spray to the 347 later if you decide you "need" more power. It's always good to have room to grow.

Looking at room to grow, that would be the only reason I can think of for you to go with a 351. It would cost a lot more to go with the 9.5 deck than to stay 8.2, especially with all the parts you already have. The only advantage would be that if you go with a 347, then spray it later you will reach the practical hp limit of the block at around 500-550 hp or so. The Windsor block can go more like 700 hp, so if you really expect to go nuts with the power maybe it would be a better starting point.

Everybody has their own opinions but I like a bigger N/A motor that doesn't have to turn as many rpms to produce the desired hp over either a smaller high revving one, or one needing a power adder to make the hp. High rpms, boost and spray are all hard on motors and will reduce reliability and longevity.

For what it would cost, and especially if high revs are in the picture I'd change over to a roller cam setup in that early block. I'm just not a fan of the flat tappet stuff.

I think I'm starting to ramble here so the Cliff notes version is with the information you've given I'd go with the 347.

[spdjnky_42]

A 347 is a good setup, but I dont think your heads (unless ported) will be good enough for the 347. The 306 is going to be your cheaper route, but the 347 definetly a better setup. Either way you will definetly want to change over to roller cam.

[RLG34750]

grant you i am bias....

but there is no replacement for displacement

I'd go with the 347.......

[Stroked95GT]

The heads and intake will definately hold you back! I have the explorer intake on my 331 and my power flatlines at 5200 rpm's because the intake runners on the intake are so small.