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A buddy of mine has got himself into an early bronco race truck. After the season ends, we're looking at building him a new motor. Doing research on Ford motors is starting to confuse me (always worked with GM motors in the past), so I'm looking to the boards here for help.
Here are our rules. Cast block, cast heads. Must be a 302 block (although he's running a 351W now and getting away with it). Must be wet sump. No limits on cams, carb (other than a single 4bbl max), bore, stroke, etc. Here are the questions: 1. How much HP can you really build into a stock Ford Block? I'm hearing from many of these racing engine builders that if you plan on going over 400-450 HP, you really should run a Ford Racing Block. The cylinder walls on the stock blocks are too thin and just won't take it. (Remember here, this is a racing motor that needs to hold together for us under high stress, no tooling around taking it easy on the street for this puppy). 2. I'm interested in the Ford Racing Heads part no. M-6049-N351 because of the 10 degree valve angle. On the Ford site, they list as only for a 351W block. What are the differences between a 302 and 351W block? Only deck height and head bolt size, or is there something more? 3. To run this motor up to about 6500-7000 RPM and make good power all the way through, what bore/stroke combinations do you Ford guys recommend? 4. Looking through the Summit and Jegs catalogs, I'm not finding many roller cam profiles for Ford small blocks that look very appealing. Any suggestions here for a good roller cam setup? Please include any other tips/suggestions you may have. Thanks in advance, Barb |
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...also look into some cam roller bearings. Ford Racing also sells these. You have to have your block machined for them. The oil feed holes can be completely blocked off becuase they only need slpash lubrication, leaving more oil for the bottom end. I would just recommend getting a Ford Racing Performance Parts cataloque. You will spend hours looking through this thing dreaming. Just a thought.
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Hey, thanks a lot guys. I'll get working with those suggestions!
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Just a side note the earliest blocks were actually 289 and don't have the extra cylindetr support in the bottom that the longer stroke 302s have9 although you can make them 302, you run the risk ( especially in a race engine) of getting some piston rocking. Plus in the mid 60's they went to 6 bolt bellhousings from the 5 that had been used so keep an eye on that. I think up to about '71-2 are as strong, and there is also the mexican block that is available at swap meets and through hemmings, they have mains cast like the 289 hi-po and are stronger than a regular block and are fairly reasonable.
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In my humble opinion, people sweat stuff that isn't an issue, such as main girdles. In my experience no one has ever seen a broken main cap from a small block Ford. This is an item some Ford racers thought they needed because a 4-bolt block wasn't readily available to them. Roller cam bearings are another great way to waste your limited racing finances. when the engine is running there is no friction between the cam and bearing. If there were, your cam bearings would be wiped out in short order, certainly not lasting the 100K+ miles that stockers do. This applies to everything Chevys, Big Block Fords..whatever. The Winston Cup guys want them because they can remove an area of windage from their dry sump engines they don't have to worry about scavenging. We're talking teenie tiny hp losses at extreme rpm from the oil escaping the oil clearance at the journal. Cam life to them is unimportant as long as the engine lasts the race weekend. Someone else is buying their parts. I would suggest defining an RPM range that you want to be in and then find a set of suitable heads after you decide what the displacement is going to be. Its a buyers market out there for Fords, but be warned, a 200 cc intake runner on a 302 will be a stone when it comes to moving a 4x4 or tough truck type dealio. After defining those parameters a cam purchase is easy. Nothing weird about a Ford with aftermarket heads. Compression is a huge factor in determining duration and lobe seperation. Its all gotta work ya know?
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I agree with the over building for the application , roller cam bearings would have to fall into that category and the only 302's I've seen that broke, cracked right through the cam bearing ( another reason not to bore it out for roller bearings)main area, and they had girdles. That's what happens in a 600hp Drag engine at who knows what RPM, but for your application and RPM range you are probably going to run all those "extras" would probably set you back enough that you could build a spare shortblock.
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FWIW, Shelby America always brazed the press-in joint on the oil pick-up tube on their 289's. Cheap insurance.
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