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7 bolt Frankenstein build?

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ncarson91

Proven Member
138
14
Jan 2, 2021
north olmsted, Ohio
I have heard of this 7bt Frankenstein setup with 1g rods 2g pistons my question is what else does it all entail? Is there a whole list of everything that goes into it? I have a spare block I’m going to rebuild would love to know for it considering it is a 2g block
 
7bt Frankenstein setup with 1g rods 2g pistons
I don't know what exactly you want to do but if you meant the 1g rod is 1g 7 bolt rod, then you are just building a 2g 7 bolt engine. Rods and crank between 1g 7 bolt and 2g rods are the same.
If you meant the 1g rod is 1g 6 bolt, then it won't fit in with a 7 bolt crank without machining. You should look for 7 bolt rods. It would be much cheaper and easier than modifying 6 bolt rods to fit in with a 7 bolt crank and pistons.
Usually when people say 2g pistons w/ 6 bolt rods, that's for a 6 bolt block. Maybe you are confused.
 
I have heard of this 7bt Frankenstein setup with 1g rods 2g pistons my question is what else does it all entail? Is there a whole list of everything that goes into it? I have a spare block I’m going to rebuild would love to know for it considering it is a 2g block
Years ago 6 bolt owners would machine the rods to accept 2g pistons as a cheap upgrade to 2g pistons at 8.5 comp ratio.
If you are using a 2g block etc none of that would apply to you.
All 7 bolt rods are the same 1g and 2g. They changed pistons in 2g.
 
Plus the 22mm wrist pin in 2g pistons. Wasn't that another reason it was being done?
 
Yeah see I’m new to hearing about all this I heard use 1g 6bolt rods crank and bearings. 2g pistons from 7 bolt . Like I said it’s all hearsay was trying to dig up more info on it

And use arp rod bolts
 
Yeah see I’m new to hearing about all this I heard use 1g 6bolt rods crank and bearings. 2g pistons from 7 bolt . Like I said it’s all hearsay was trying to dig up more info on it
If you're using a 2g block you use 7 bolt rods. There isn't a mix and match game to be played for the most part on the rotating assembly. Really just pistons and we only did it way back when because there weren't tons of choices like today. Even then to put a 2g piston on a 6 bolt rod you had to custom machine the 6 bolt rod ends to accept the 2g piston. There is simply no reason to do this anymore.
If you're building a 2g block (which is automatically a 7bolt) choose the parts you want off the shelf. Understand what your goals are and what is required.
You can overbuild as much as your wallet allows but you shouldn't underbuild. The "frankenstein" build you refer to really wasn't some crazy project and isn't done much anymore to my knowledge.

 
no i know i was just trying to gather information on it. thats why i posted this because it was something i heard that i was clueless on but heard it helps reduce running risk of crankwalk.

thats just something always in the back of my mind. thats why i figured id ask and see what info people knew about it and what parts ect i can use on my rebuild so i can worry less.

right now its stock internals. new head gasket all the maitence is done. 1000cc injectors, fpr, fuel pump 255, 20g turbo bolt on big front mount. new clutch and flywheel, new axels, brake upgrade. running on premium not E85.

i disabled in ecm the where you have to press clutch to start car. heard that was a common thing to increase the chance of crankwalk
 
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no i know i was just trying to gather information on it. thats why i posted this because it was something i heard that i was clueless on but heard it helps reduce running risk of crankwalk.
nope. 2g pistons on 1g rods does not affect nor cure crankwalk.
thats just something always in the back of my mind. thats why i figured id ask and see what info people knew about it and what parts ect i can use on my rebuild so i can worry less.
 
Plus the 22mm wrist pin in 2g pistons. Wasn't that another reason it was being done?

People didn't do this to get 22mm wrist pins, they did it as a cheap way to get 8.5:1 compression pistons and had to bore and narrow the small end of the 6 bolt rod to fit the 2G wrist pin and piston.
 
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