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Author Topic:   ? for steve.
rickb33
Member
posted May 30, 2003 11:45 PM
The 2.020"/1.600" is your best choice if your aloud to blend the bowl's . As for getting more from your next set up , I'd need to look at your rules and explore the "gray" area's a bit .

Steve

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Hendren Racing Engines
Rutherfordton , NC
(828)286-0780


WPP
Member
posted June 01, 2003 12:10 PM
Steve how big of valves can you put in a 461 or 487 can you go to 2.05 and also how much can you angle mill these heads i am trying to get all the compression i can we are going to try to get a 400 block with a 6.125 rod a 400 steel crank gring to a small journal more like a project for my dad he is bored and retired he loved the the 350 cranks grind down to a small journal but now he wants to do the 400 this motor is on akly could you make some power with this and the heads


sdhnc29
Member
posted June 01, 2003 12:46 PM
You can go to the 2.055"/1.600" valve combo in the 461 head's , but you will need to have your machine shop of choice unshroud the combustion chamber . You can roll the 461 head over .145" safely . This is measuring across the deck of the head , not all the way across to the intake runner's . You will also need to use pin's that are used for crack repair , and plug the two 1/4 " spark plug cooling water holes on each cylinder , or the fire ring on the head gasket will not seal once the heads are angle milled . Also , you will need to spot face the head bolt holes , as well as correct the bolt hole angle so your stud's/bolt's wont bind up in the head bolt hole's . You should also have your machine shop correct the intake and exhaust face of the head's once they are angle milled . This will put both faces back to stock angle , and make fitting an intake manifold and header's much easier .

Ultimately if your going to build a 400 , and if your rules allow for it , I would not use OEM head's . The OEM head will be your restriction as to how much power you can produce . If your set on using a flat top piston , I would use the new 49cc Dart Iron Eagle . After finally getting a set in the other day , I think we can get these head's extremely small on combustion chamber size with little effort . Remember that alky engines love large intake runner's , and a ton of compression . I'd use the 230cc Iron Eagle , and shoot for a minimum of 14:1 on compression .

Keep in mind that any 3.750" stroke steel crank that you find will be an aftermarket crank . If you are trying to grind one from large journal to small journal , this crank will need to be re- nitrited . Make sure that whatever shop grind's your crank leaves as large a radius as the original one for the rod journals . Regardless , this will be a short life combo due to the overlap of the rod and main journals being separated even more by grinding the crank to small journal . This is something that I would recommend taking apart every 10-12 races and magnifluxing the crank , block and main cap's . Once you reach the power level that it appears you all are shooting for , the stock OEM block will not live long . You will find that it will break out of the main webbing and extend down to the cam journals .

Feel free to call or write if you have any more questions .

Steve

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Hendren Racing Engines
Rutherfordton , NC
(828)286-0780


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