i would like to know what to do to stroke a 425 using a 364 crank and any down side of doing this. thanks
It is however you can get a crank bushing from Russ Martin that will allow you to use a later trans with the early crank. However, I've never heard of stroking a 425 with a 364 crank.
if I am not mistaken, the 364 has a different journal for the thrust bearing that will need to be addressed as well. Better to have stock crank ground to use Chevy type rods and have pistons made.
that is a lot of cash to do all that. unless you are racing i would just rebuild the nail and enjoy it. jd karnes
Actually, I dont think that will work.... as engines get bigger the cranks are stroked out or the bore increased or a combo of both.... if you put a 364 crank into a 425 it is going to destroke the engine....decreasing cubes....plus the other differences if any....
The bushing? I think it only work with 364's, 401's, and 425's. Did they make a 425 in '63 with a Dynaflow? That's what I was thinking. Seemed a little odd to me .
sorry guys it must be can you use 364 rods and not the 364 crank somebody said chevy rods will work too. sorry for the mix up
The 364 crank has a SHORTER stroke than the 425. But....Using the 364 rods in a 425 that has a 1/4" stroker crank is a very economical way to more cubic inches. ---Jim
You can use 364 rods in a 401/425 for a 1/8th. inch stroke. The crank needs to be welded up then re-cut. This is NOT an economical or very smart way to do this today. It was many years ago when rod choices were at a minimum. Why would you want to increase cubic inches anyway. A fully ported set of heads can barely flow & support 320 cubes let alone 400+. Just my thoughts on the subject.
Tom, is right on,,,, Back in the day, the way a engine was stroked was to build the journals toward the out side with weld and then turn the crank to the new stroke and then get it re heat treated.... a very complex proceedure, and now days you can get a billet crank made,,, which would be a better set up,strength wise,,, but again, like Tom says , ''Why"????? A man cannot over come all the limitations of any engine,,, that is why there are classes set up at the strip,,,, just run in your class and be content....i saw a guy at the strip, running a econo dragster that had a little mg engine, and he was having a blast.... did not need all that exotic stuff to have fun....
you guys are right its fast now just thought it might be easy to stroke but its not and cost to much. just want to go faster and faster its in my blood lol
a very complex proceedure, and now days you can get a billet crank made Why? Billet crank = $2,500. Welded crank = $800. Unless you need to change the compression distance, the rod length change to "zero out" is 50% of the stroke increase. Example: 1/4" stroke increase (with the same journal size, billet or welded) requires 1/8" shorter rod for the same deck height (the 364 rod in the 425 is very close at 6.100"; 425 rod: 6.219" - .125" = 6.094"). However, the stock piston may strike the counterweights etc. Regrinding to a smaller journal requires a smaller rod such as early SBC at 2.00". Maximum possible stroke increase is .250" (journal size difference: 2.250" - 2.000"), which would also require a 1/8" shorter rod Typically, you'd use a custom piston rather than modifying a stock one, so the rod length might actually increase and the adjustment be taken to the compression height.
In reality there is really NO cost effective way to do this. Just about no matter what you do will require custom pistons at about 1K cost. You also need to remember rod/stroke ratio for con rod length & the syn factor also comes into play. Know what that is & the way to figure it out???? A much more cost effective way is with a set of my "Adjustable, Variable Ratio Roller Tip Rocker Arms". Many benefits with little or NO downsides. Ask any here that have used them. Tom T.
my fastest et's were with 456 gears and a solid cam 274 @ .050 with ported heads and sbc stainless valves 1.94/150 stock rockers and adj pushrds run upsidedown,401 or 425 12-1 cast 401 and 12-1 forged 425 theyre both still in my garage and never broke yet,i have about 50 passes on my 425 and i was shifting at 6700 and went thru the traps at about 6300 30x9 rear slicks 3550 lb car. went 11.97 @ 111 at union grove in 98 the trick to rpm is a balanced motor and good valve springs from carmen faso and well ported heads,stock heads nose over about 5k,everyone says dont rev buicks but my ported heads love rpm and to be honest im not sure when they nose over i shifted at 6700 to be conservative. i have 2 sets of 364 mickey thompson alumn rods 1 set new 1 set used like new,ive never used them yet but wonder what rpm could be had. ive heard of some real bad axx 4.25 bore 364+ i have 2 364's i never got around to in my garage 1 std and 1 4.25 bore balanced 12-1 nailheads can be alot faster than most end up,just keep trying ken (ugottagonailhead@cs.com)
