Sorry to start a new thread, but this is different line of questions..sort of. I have been reading that Ford started skimping on the material for the blocks in later years, so if I bought a newer (90s model) 351W block, would I be safer doing a less stroked and bored motor rather than the full 393/406? If I am putting a couple thousand bucks into this project, I don't want to crack the block first thing. Also, I was thinking about a decent shot of nitrous, maybe 150-shot on top of it, for some more torque. I am guessing...maybe close to 500 HP with the shot on it? Would a not-quite-so-stroked motor (the 351 equivalent to a 331 stroker) be a better bet? While the 351 is in the car, I will build the 302 up to a 347, since it will be just sitting around. If I ever sold the car, the numbers matching 347 would go back in, just in case in might increase the value of the sale. Any good advice?
Simple. Main girdle & studs. Then go for the 393/408 setup. Make sure you use good rods and pistons. The later roller block is fine up to around 650-700 hp.
I will go one step further, beyond the girdle and main studs... Head studs and block filler. Also, don't do the 393 if you want to beat the engine. This stroker is a budget type and uses stock rods and 302 pistons. Sure you could build a beefed 393, but if you have to buy aftermarket rods and special pistons... You might as well just do the 408! Same price, more cubes, and stuff is readily available. Beefed 393 stuff is not as common because the reason for the stroke is to use the stock stuff. Roller blocks weren't till 94. Also, your block won't handle the huge levels of power until you have top notch machine work done! Balance, blueprint, tap threads, magnaflux, deck, line bore, floating pins, sonic check, deburr, etc... Skip any steps and you are risking a short life for the engine and all the dough you put in. Dave
So, year model of the block is not really a factor? I want to buy a beefy block if I can. So I can BEAT IT! Otherwise, I will 347 my 302 and BEAT IT! I have found a good machine shop, so that shouldn't be a problem. When did the 351W become a roller...I will look for that block if I can.
http://www.fordracingparts.com/parts/category.asp?catID=38&catdesc=Engine%20Blocks Specifically, the Sportsman III block. Or you can find an earlier Sportsman 351 block. Usually the circle track guys have a few. I'd simply find an early ('69-72) 351W block and work from there. When I said studs earlier I meant mains and head studs. As for filling the block.....depends on how much street driving you're going to do. You need to leave some amount of room at the top of the bores for coolant circulation. Say...1 1/2" or so. Most people make the mistake of filling the block to within 1" of the deck and then can't figure out why the car won't stay cool while they're circling the Sonic on Saturday night. The 351 roller blocks were 94/95 models I believe. However, they are cast similarly to the roller 302 blocks. They'll take a bit more power but I wouldn't push 700 hp through one. If you stick with the 302 then you can find a Mexican block to start with. Or perhaps a Sportsman 302 block somewhere. Your decision will ultimately be based on what you have in mind for your total combination and ultimate power output. I know that B&G Machine is down in your area (Alvin). They're about the best Ford guys around until you come into town. USA Racing Engines, Harris Engine & Grinding, Faerman Machine are a few others with good Ford experience.
B&G are the guys I talked to, and their prices were fair/reasonable. Only 30 minutes from home. I will keep an eye out for those older blocks. I am in no hurry, and am having a good time with the 302. I will just keep my eyes open, and maybe read the book just for some ideas and preparation. Might keep an eye on ebay but will probably have better luck finding cheap stock in the junk yards. I don't need anything special, just the block. Anything else will be thrown out.
re 351 w - can a 1 piece seal crank be used in a 2 pc seal block? can a 2 pc seal crank be used in a 1 pc seal block? if not, what must be done to permit it?
Yep on the first one. The two piece crank can be modified to use in the one piiece block by grinding off the oil slinger/diverter. Good crank grinder can handle that, "OR" take a block and set it on the floor with the mains up. Put in a three main bearing inserts (used one's will do). Install the crank and caps with a turning socket or just the blancer bolt in the snout. Have a helper use a slow rpm drill motor or the like, turn the crank. Then you can take a 4 or 5in surface grinder and slowly remove the slinger down to within about a 1/16th of the surface. If you are good, you can take it down even, but really don't need too. Use some emery cloth to dress up your work and then "WASH" and clean the crank repeatdedly. Works like a champ for me.
On the 351w blocks...MOST are good to 500+ HP easily. The early (before '74) were supposedly a little better, but I have yet to confirm that. Where the main webs meet the main bulkheads, the early blocks are more radiused. The later ones have a sharp 90 degree turn, which I'm ASSuming can be a great place for a crack to start. On the the last 351w I grenaded, all the mains were broken out of the block. Do a search--there were some pretty good pics of how the mains split right out of the block. It was an E4AE block, FWIW. Now keep in mind that it was never balanced, used a cast iron crank, 14.8 compression and it was alcohol injected....and it lived a HARD, high RPM life for 2 seasons. One race day I started it up and noticed that the oil pressure was 20 psi. Ran fine, I think I won that race even. Next race, it still had 20 psi, hot or cold-didn't matter. RPM didn't matter either. Made it to the 3rd round of elims and JUST before I shifted (around 7000 RPM, it let go--with a bang. Locked the entire drivetrain up instantly. Went from accelerating forward to skidding the rear tires almost instantly--until the trans lost pressure and it freewheeled. It wasn't pretty. Like I said, keep in mind that it wasn't balanced--it vibrated from day one, and that's probably what did it in. Crank was in 4 pieces, 4 main webs were still attatched to the crank parts but they just split right out of the block. The 415"w I have now is filled with concrete, balanced, and so far so good. Going on it's 2nd season of abuse. Hopefully it lasts at least until the end of this season. They all blow, it just is a matter of when and how bad.....trust me. If you're going to spray it, I say get a GOOD balanced rotating assembly, steel crank and aluminum rods....they tend to take up a lot of the shock load better than steel rods do especially when being gassed with the giggle stuff. Oh and on the 347 deal...those 302 blocks are notorious for splitting down the middle. They all do it eventually with enough power. How long they last is like asking how long your tires last...sometimes they go forever and a day, sometimes they make 1 pass and let go, it's just a gamble.
I second his statement... We have done that to my 302 after my buddy cracked my block with a torch. lmao
