i want to do new rod bearings

Rideracelivemx7 · Apr 7, 2013

So my motor is coming out in a couple weeks to install my new heads I had whipped up and install a few more goodies. I sent out a low mileage set of forged rods I bought to be cryod to give me a little more confidence in running 350/200s and ported heads. I was told not to touch the motor until I do new pistons and rings but im not doing a full refresh for another year or so. Could I not just install new rod bearings with the treated rods if I keep the pistons and rings in the same spot to the best of my ability when replacing the rods?

next season I was going to pull the motor, run fire rings, have the motor cleaned up and check at a machine shop. install billet rods and install my second charger with all new pistons and rings. So I don't want to run new rings thing time around as it doesn't really make sense too me.

bad12jr · Apr 7, 2013

I'd just leave the pan on and not touch it. One of those if it ain't broke don't fix it deals. Id find a rebuildable long block. Then put the rotating assembly together and throw the spare parts on your current motor for a spare.

Sent from my x2 chillin in the middle of no where

Rideracelivemx7 · Apr 7, 2013

well im not worried about down time and I don't really need or have space for a spare motor. id prefer to run my original block, im doing my best to run some more power and keep it in tact. I figure treated rods with all new bushings and bearings will make the ol girl sound a little better and hold the power.

DEEZUZ · Apr 7, 2013

doubt it... but ok

DocBar · Apr 8, 2013

bad12jr said:
I'd just leave the pan on and not touch it. One of those if it ain't broke don't fix it deals. Id find a rebuildable long block. Then put the rotating assembly together and throw the spare parts on your current motor for a spare.

Sent from my x2 chillin in the middle of no where

I'd try to make room for a spare block and run what I had til it broke or I had the spare motor ready.
You can always store that spare block at a good machine shop for a bit. Good machine shops are usually busy and you could tell them you are in no hurry at all.

Do you think the cryo job on forged rods add much strength? Not being a smart a$$, just asking your opinion. I've heard differing opinions on them.

TyCorr · Apr 8, 2013

I have read alot and the people that know, fwiw, say to leave a forged rod motor be. Ive even been told its wreckless to do anything once you tear it open BUT billet rods. I kind of agree. Having never.done anything but remove pmrs and put.forged rods in, im no expert. Buuut.the sources of.said advice are.

My other 7.3 was an 03 and had FR, I kid you not. Dont know how or why it was that way. Anyway, that is neither relevant nor on topic here.

Good luck with your decisions!

P.S.-thats a lot of fuel for forged rods. 650ish.

2000wa250 · Apr 12, 2013

Like they said, do it right once, or keep doing it. If you're dead set of pulling the pan and swapping the cryo'd rods in, throw new rings in along with a cylinder hone. If you dont want to throw rings and hone the cylinders, then do not crack bottom end. No point in breaking the seal on the rings for fresh bearings and rods if you're not going to do it right.

With that fuel, I would second the spare engine/block idea. Have it tuned to limit torque, and tell your tuner that you want the power in the upper RPM's to keep cylinder pressures down. It wont feel as fun to drive, but it will keep it alive for awhile. Basically just buy yourself enough time to build your spare motor. Once you have the bottom end built and balanced, pull your engine, swap everything off it, and run the piss out of your built one, knowing you took your time and did it right.

Personally for me, its not a matter of time down, or money, its a matter of piece of mind. No point in spending all this money on injectors, turbo, hpop, studs, springs, etc and then skimp on the bottom end because you do not want to throw new rings in it with your "new" rods. Do it right and do it once.

907DAVE · Apr 12, 2013

Agreed with everything so far.

OP, I was in your shoes once with my PMR's. Had the works done to some forged rods - did the entire swap and freshened up the motor while it was apart only to pop one a year later.

I could have saved a bunch of money if I had put a set of billet rods in from the get go.