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I remember reading a few articles a while ago about stroking a 400 to 427 just by offset grinding the crank, sorta a poor mans stroker kit. You ofset grind the crank and use 240 rods I believe. But im not sure what pistons and what the offset grind was. Has anyone heard of this or know anything about it??
okay i will. i did the math on it and it would require an .085 offset grind of the crank to make 427inches with a .060 overbore. that seems like an awful lot of metal to remove, is it even possible to remove that much metal and have a crank that is still structurally sound?
okay i will. i did the math on it and it would require an .085 offset grind of the crank to make 427inches with a .060 overbore. that seems like an awful lot of metal to remove, is it even possible to remove that much metal and have a crank that is still structurally sound?
This has been discussed several times on here and the 335 Series Yahoo Group. A couple of guys have posted their builds. Try doing a search, you may get lucky. From the builds as I remember, they used a .030 over bore with a 240 6-cyl rod and offset ground the crank to 4.17". IIRC, they all used an off-the-shelf piston but I cannot recall for what engine. If you have to pay someone to weld up and then grind the crank plus balancing the odd-ball mix of parts, you would be better off buying a 434ci stroker kit from TMI. You will get stronger rods and crank plus specific pistons that will work with you current heads. There are so many little details that you will not have to worry about with one of his kits....oh, not to mention you get 7ci more.
yea i know i just wanted to see how feasible it would be. i would love to run the tmi stroker kit, but thats probably going to be out of my price range. just wanted to check out all the options.
As long as the 240 rod bearing size is no larger than the 400 rod journal size + .180, then offset grinding is no big deal as long as you are building a reasonable RPM street engine. Strokers have been built this way forever.
I think I did the math on this one a long time ago and it worked. I even had a top notch crank grinder ready to do it, but something came up and I didn't do the build at that time.
As long as the math works out, it is an economy way to build in LOTS of torque to an engine already capable of being a torque monster if built with a short cam, small runner dual plane and better yet add some small tube headers. If you did all that you would be ready to bolt it in your Bulldozer to add torque to it.
As long as the 240 rod bearing size is no larger than the 400 rod journal size + .180, then offset grinding is no big deal as long as you are building a reasonable RPM street engine. Strokers have been built this way forever.
I think I did the math on this one a long time ago and it worked. I even had a top notch crank grinder ready to do it, but something came up and I didn't do the build at that time.
As long as the math works out, it is an economy way to build in LOTS of torque to an engine already capable of being a torque monster if built with a short cam, small runner dual plane and better yet add some small tube headers. If you did all that you would be ready to bolt it in your Bulldozer to add torque to it.
The problem for a lot of guys is finding a machinist they can trust and is even capable of doing the work.
I build most of my own stuff but I use a machinist that is about 800 miles from me. Not by choice but because I can't find anyone I trust to do anything more than bore a Chevy .030 over.
When I built my 400, I talked with my machinist about a 427ci stroker and his labor rates plus all the running back and forth was not even close to being economical. I could build a 427/434ci Windsor for less than what I could my 400 econo stroker.
TMI has really made the 434ci a slam dunk for guys like me that have to pay for machine work but can mic components and assemble a long block.
Well im blessed with having a great machinest 15 miles from my house, he has been at the same place for 40 years and now his son helps him so he is definatly a real smart and trustworthy guy. He has done all my machine work in the past and never had any problems with him and i dont think i have ever heard anything bad about anything he has done. About what would it cost to have a crank ground like this?
I have an update. The 427 uses a 4.17 inch stroke which requires the crank to be offset ground .085 to make the crank throw 2.085 inches. Using the 6.7947 inch 240 rod, the compression hight comes in at 1.3873 based on a virgin block with a deck hight of 10.267. The chevy 327 using a 6 inch rod has a compression hight of 1.385, perfect for as it also has a .927 inch pin diameter, same as the 240 rod. Hope this helps.
I have an update. The 427 uses a 4.17 inch stroke which requires the crank to be offset ground .085 to make the crank throw 2.085 inches. Using the 6.7947 inch 240 rod, the compression hight comes in at 1.3873 based on a virgin block with a deck hight of 10.267. The chevy 327 using a 6 inch rod has a compression hight of 1.385, perfect for as it also has a .927 inch pin diameter, same as the 240 rod. Hope this helps.
The valve reliefs will be in the wrong place for your canted valve heads. You will need to check for valve clearance if you run a piston that is made for a wedge head.