about to do 1g rods/2g pistons

[nazthug]

Ok, a few questions

I am going to pull out my pistons and re-ring them as its about that time. At the same time I also want to replace my 2g rods with 1g rods because they are stronger

I was going to do a full build but dont want to pull the whole engine out and have it machined, so i will just throw my 2g pistons back in with new rings.

I know I have to machine hte rods to fit. What rod bearings do I use? I want new mitsu ones, not sure which ones to use???

Also, arp bolts?? I will have the rods machined and arp bolts installed, what else should I do?

I just want to freshen up my engine a bit and at the same time strengthen it a bit as well, I have good tuning and a very safe tune and am only aiming at 400whp(im at 365whp right now) so i dont really need forged pistons

I will also send out my head to get new guides put in as well as a valve job and a new headgasket and arp head studs, so the whole combo should be very cost efficient and be plenty strong enough for consistant 400whp outputs

 

[99gst_racer]

The main and rod bearing are different between the 6&7-bolt engines. Get your rod bearings for a 6-bolt (Clevite part number CB1120AL) and get your main bearings for your 7-bolt block (Clevite part number MS2039P).

If you're not going to machine the block, at least hone the cylinder walls.
That's something you can do yourself with a drill and a hone. You can pick up a stone glaze hone at most parts stores (as well as Sears) for about $20-$25. If you want to use a ball/bead hone, they typically will run you about $35-$40. The stone type is much easier to find though.

Get rings for a 2G and make sure you file them and gap them correctly.

Make sure whoever assembles the block stretches the rod bolts before use. I would also recommend having the rod bore resized (i'm referring to the big end).

ARP fasteners for the rods, mains, and head.

 

[nazthug]

so rod bearings for a 6 bolt on the 1g rods will fit the 7bolt crank without any crank machining?

I will hone the cylinders if needed, but most likely it still has the swirl marks on it, and in that case, i'll leave it alone, and just file gap the rings accorndingly

What do you mean stretch the rod bolts?? How do you do that? I will probably just pick up a set of brand new 1g rods because im weary of buying used rods that have 100,000+ miles on them, they must have alot of stress on them

 

[nazthug]

also when i look up new rods, they have them from 5/92 on or before that...which ones am I looking for? What is the difference?

 

[99gst_racer]

so rod bearings for a 6 bolt on the 1g rods will fit the 7bolt crank without any crank machining?

Well, as always, if the crank journals need machining, then you will need to buy oversized bearings. That all depends on the condition of the crank. Have it checked by a machinist. Other than that, they will fit fine.

I will hone the cylinders if needed, but most likely it still has the swirl marks on it, and in that case, i'll leave it alone, and just file gap the rings accorndingly.

Hone the cylinders anyway. Unless it was just recently done, go ahead a do it. You only need to remove the glaze on the cylinder walls. That only takes a couple passes with a stone type hone. You're not really removing much material at all, but I'd still recommend doing it. I just honed a block last night. It didn't look like it needed it, but it sure felt like it did.

What do you mean stretch the rod bolts?? How do you do that?

Read through your own thread.... Read post #'s 10, 14, and 15

also when i look up new rods, they have them from 5/92 on or before that...which ones am I looking for? What is the difference?

Yes, get the rods for the 6-bolt engine. That would be for engines before 5/92.

 

[bryanwheat]

What are you talking about. There would be quite some machining involved in putting big rods in a 7 bolt motor. They are wider . Not worth the money for the machine work. The rods are not the problem with the 7 bolt motor. It is the face that you are only getting 10-15 psi of oil pressure to the main and rod bearings. Build a 6 bolt, There is also going to be about 20-30 per rod of machine work to put the 2g pistons on the 1g rod. You just need to build a 6 bolt and use that 7 bolt as a paper weight.

 

[GSTinCO]

What are you talking about. There would be quite some machining involved in putting big rods in a 7 bolt motor. They are wider . Not worth the money for the machine work. The rods are not the problem with the 7 bolt motor. It is the face that you are only getting 10-15 psi of oil pressure to the main and rod bearings. Build a 6 bolt, There is also going to be about 20-30 per rod of machine work to put the 2g pistons on the 1g rod. You just need to build a 6 bolt and use that 7 bolt as a paper weight.

What kind of machining would be required to put 1G big rods in a 2G besides on the piston end? thanks

 

[gsxtacy]

Thats the thing.

1G 6 bolt rods are NEVER put on a 7 bolt crankshaft because the BIG END is WIDER on the 6 BOLT ROD and Crankshaft (in the journal area), and if your gonna go as far as upgrading rods on a 7 bolt,.......BUY a set of 7 bolt Eagle rods.

If your gonna build/rebuild a block, save time, money, stress, BUILD a 6 bolt.

gsxtacy