Big rods are the 6 bolt 1g rods,and they are on both the 4g63 turbo and 4g63 non turbo.The 1g 7 bolt rods are a bit thinner,and can't take as much power as the "big rods".And yes,1g's have both 6 and 7 bolt.They switched in the middle of 92.

The stock 1g internals are good for around 500 hp as long as everything is set up right. The stock 1g rods are good for around 28 psi.

1g rods can handle alot more then half the people throw at them before switching them out. You can get them shotpeened as well. I believe FFWD might cryo them too. I wouldn't push them much past 400awhp though.

timloomis said:

Big rods are the 6 bolt 1g rods,and they are on both the 4g63 turbo and 4g63 non turbo.The 1g 7 bolt rods are a bit thinner,and can't take as much power as the "big rods".And yes,1g's have both 6 and 7 bolt.They switched in the middle of 92.

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So is it possible to mount the 1G Big Rods on a 1G 7-Bolt Crank with little or no machining? I am thinking of running them with 2G Pistons to get the 8.5:1 compression ration. I realize inorder to fit the 2G Pistons on the 1G rod I need to have 0.100 inch taken off of the top and wrist pin enlarged to 22 mm. Such as the drawing below from RRE says to do. But nothing around the crank area is requried? Or does it? And is it really worth it to do?

The reason I am asking is because I am getting a 1G 7Bolt shortblock and head for very cheap (needs new rings) and since I have to put new rings on, I might as well a rebuild on it. So I am thinking of replacing the 1G 7-Bolt Rods with 1G Big Rods, machining the rods to fit 2G pistons then reassemble it all. Is this doable? Obviously, anything is doable I am mainly asking if the cost savings is worth it or should I spend a the extra (possibly twice as much) and get some billit rods and pistons that are 0.020 over?

Edit: One other question, what if I put a 7-bolt 2.4L crank from like 4g64 in, then used 1G Big Rods, and the "special" stroker pistons. Would that combination work great with a 1G head for 2.3L?

Yes, that combination would be fine. But I suggest doing a build only once, so you're going to need to evaluate what you want out of the car. Do you want to spend the time and money it takes for a stroker? If so, why not spend a little extra money getting the forged internals?

I agree Brute about doing it once right. But I justed wanted you to clarrify a little if you could, there is no problem putting 1G Big Rods onto a 7-bolt crank. Would you use 6 bolt or 7 bolt bearings?

i thought the crank and bearings were different from 6bolt to 7? And the flywheels are different...

I thought that too Nightspeed. I'm hoping someone will clarify this for me.

Besides making the changes to the wrist pin area of the 1G Big Rods to accomodate the 2G pistons, what needs to be done to the crank area to put it on a 1G 7-bolt crank? Any?

I actually sold an extra set of 1g rods to a guy a while back.He put them in a 1g 7 bolt.He told me the machine shop had to shave the crank end of the rods a few thousandths to get them to spec out right,but they do fit.

why dont you get 1G pistons and 1G big rods, so the only thing you will have to do is shave a little of by the crank. if you get 1G pistons you wont have to shave anything off for the wristpin and so on.

timloomis said:

I actually sold an extra set of 1g rods to a guy a while back.He put them in a 1g 7 bolt.He told me the machine shop had to shave the crank end of the rods a few thousandths to get them to spec out right,but they do fit.

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This dosen't make any sense why a machine shop would do this. Wouldn't the rode I.D. become out of round? Perhaps he got the rod caps switched around?

They didnt bore it out,they took some off the sides of the rod.Just like shaving the rods for 2g pistons,but the crank side instead.

Ok, so the consensus seems to be, 7-bolt rods (aftermarket) will fit both 1G and 2G 7-bolt motors no problem and use 7-bolt bearings. 6-bolt rods can be machined to work but the cost savings may not warrent it. And the 6-bolt rods could be used after machining on a 7-bolt with 7-bolt bearings.

So with that said, what is the favored rod/piston combo that will allow ~8.5:1 compression (I am sticking to this because I have been told it is the best ratio for our turbo engines in regards to knock versus low end torque... if someone differs, please correct me and explain why) and can handle a max at the wheel power of ~400 hp as that is my end goal in a year or so.

Also what head work to a 1G 7-bolt is suggested to go along with that power? I am thinking of going with the 3G revised lifters, Brian Crower Racing springs and Ti Retainers and FFWD DKS1 Cams (264/272).

Any suggestions? Comments? Personal preferances? I plan on slowly (very slowly, over the next 6-8 months building the engine up) getting the parts, machining the engine and assembling it for the swap.