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Discussion Starter #1
ever body is crazy for stroke 'n inches. Can any body point me to an off the shelf 289 2.87 stroke crank that'll take 500 horses and 7900 rpm
 

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Good luck with that, the demand is just about NILL
 

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How about the one that Ford included with the car when it was new? I know firsthand that they can take a lot of abuse. If you prep it right, it should last a long time-MagnaFlux, shotpeen, extra radius ground in, careful balancing along with good rods and pistons. I think the valve train is more of a weak point at 7900 RPM.
 

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I agree with 67 and FE. I had good luck with a mid 70's 302 crank shifting at 7700. Even with stock rods and TRW pistons. I never gave the crank a thought, but the rods scared me.

edit: if you are going to buy a forged rotating assembly, why not stroke it and still go 7900. It will sound the same and be alot more fun to drive.
 

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Go to mustangsandmore.com and ask Alex Denysenko about 289s. Alex, who goes by Moneymaker, professionally drag races a naturally aspirated 289 powered coupe that runs in the 10s
 

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I looked for an aftermarket 289 crank for a little while, for the same reason you mention, but just as a curiosity. Didn't find anything, but found a lot of 302 cranks, so I figure if the day ever did come that I felt I needed an aftermarket crank, just use a 302 crank, it's not THAT much of a difference. Or if you've already invested in nice 289 rods (like me) there's the option of building a 331 with the 289 length rods and the right pistons (can't remember who on here did it, but it seemed to work well).
 

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Discussion Starter #8
Guy thanks for your help. John Garutti at Cobra Automotive has got one for me. Apparently they have a standing order with Scat for 4340 forgies. Here in Australia if you want to race in pre '65 historic classes you can only use the stroke that was available in the day. The stock crank is a beauty but no matter what you do even cryo treatment they will eventually let go which is ok I guess but the damage to the block and rods is the problem. Happy Trails RV
 

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Do they perform tear downs?
 

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Discussion Starter #10
Mate they get sealed on assembly after being scrutinised and if you start winning and someone protests your 'too good' performance the first thing they do is put the balloon on the plug hole to measure the cc's of air generated by your bore and stroke. Stroke is 2.87 X bore 4" plus up to60 thou. Truth be known I'd rather straight and fair.
 

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Acording to Ak Miller the upper limit for the stock 289 cast iron crank is 7-7200 RPM. I would look for a forged steel crank and integral main cap / girdle setup. You can have a 302 forging blank turned to 289 specs. I would stay away from any weld-up re-ground cranks for obvious reasons - 7500 of them. I don't know what the difference in piston speed is between 7200 and 7500 but if you are going to turn it that high a lot you might consider using the new boss block with a 289 crank - unless the rules say you have to use a stock block.
 

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Your waisting your money looking for a Forged crank, The over lap and cast materials on the stock stuff is fine for 8000 Rpm and 500hp in a drag application. Use Light pistons and Get Great race quality machine work.

The top end is where your going to need the money and maintence.
 

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dont waste your time trying to find an aftermarket crank for a 289. you will split the block long before you break a crank.
 

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4340 forged crank, Honda/IRL journals (easy 0.240+ destroke with full-sized crankpins)
5.565-inch rod with ~1.200 PCH, or up to ~144.00-mm rod with ~27.8-mm PCH
0.927 pins are stronger; use a metric 3-ring stack

it's not as cheap as stock parts; even if you've got Bill Gates' piggy bank, you can spend easily more than you have -- but Callies, Crower, Eagle, Scat all have reasonably-priced cranks, etc.

echo valvetrain being the #1 concern for high rpm
 

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i ran a 289 original cobra engine in the 70s extensive port work cut into the water passigis and brazed back up bottum end stock hi pro 2.87 st. custom ground ford e cam from bud moore 8500 RPM. all the time hard to haing on to....,. going to build another one day with boss heads and 4 weber's will use a stock 289 cast crank but have it internally balanced this time should be good for 9000 RPM no prob...
 

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Guy thanks for your help. John Garutti at Cobra Automotive has got one for me. Apparently they have a standing order with Scat for 4340 forgies. Here in Australia if you want to race in pre '65 historic classes you can only use the stroke that was available in the day. The stock crank is a beauty but no matter what you do even cryo treatment they will eventually let go which is ok I guess but the damage to the block and rods is the problem. Happy Trails RV

Roger,
Vintage road racing is beyond the capability of the stock cast 289 crank. Ford discovered this in the '60s and used forgings for the GT40s and trans Am 289s in '67. Cobra Automotive's 289s are well above 500 HP and if they use a forged crank , you should be too. Most of the west coast ( USA) vintage guys use a forged 2.87 stroke with a 5.7 long rod. Cobra Automotive can use a different cast iron head than we can and uses a shorter rod because of it. Go neutral on the balance to save cracking the block at the number 2 main web ( another road race situation). Like other responders , "I" have never "broken a 289 crank but I know road racers who have.
Randy
 

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Most of the west coast ( USA) vintage guys use a forged 2.87 stroke with a 5.7 long rod.
Randy
where do they find a piston with a 1" compression height????
 

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where do they find a piston with a 1" compression height????
1.149". There are Chevy pistons out there that are very close to this compression height. This plus a 5.7 Chevy rod makes for a nice combo for a high winding 289.

Just want to clarifiy for those who are just learning. When someone says a crank is good for some max rpm, it is important to specify if this is with stock rods and pistons or not. One of the largest forces on a crank and rods are the G forces created when the piston changes direction at TDC and BDC. 1000's of Gs are not uncommon and suddenly that heavy piston is resulting in forces measured in tons!. Using a lightweight shorter compression height piston and a longer rod that does not offset the weight savings (not usually the case) will extend a crank max rpm range significantly.

I knew a guy (don't we all) that had a 289 powered rail in the 60s. He used 289 Hi Po cranks, magnafluxed them and ran them to over 10,000. He said that guys who ran 301 Chevies (283 bored out to 4"00) used to hit these rpms and higher in the early 60s before the 327 came out.
 

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what the hell kind of valve springs were they using. i think this is old wives tales
 
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