ckpitt55

iTrader: (4)

I need to replace my pistons due to excessive piston-bore clearances - can anyone recommend me a good forged set that can be used with stock rods? Selection seems to be severely limited without going to aftermarket rods. I've got ARP 8470 rod bolts, and I'm not looking to add juice or F/I or spin to the moon. Just a mild street build for my daily driver so I can't justify forged rods.

I was looking at bumping up my compression - found a set of Wiseco Pro Tru +4 cc dome pistons @ TSP configured for stock stroke and rod length that would bump me up to ~11:1 with a 0.040" gasket and an ideal 0.036" quench. However it's unclear to me what the deal with the wrist pin is .... In the TSP description it says its designed for fitment in the stock rods, but the pin is listed at 0.943". Isn't OE 0.945"? Would I get the proper press fit with the smaller pin?

65panel5.3

yes 0.943 would be a floating pin as 0.945 is stock ls1 pin diamater, sounds to me like those pistons would work for you. there are some 927 and some 945 pins just depends on who makes them from what ive seen.

ckpitt55

iTrader: (4)

this may be a question for wiseco, but would anything special need to be done to the small end of the rod as far as machining? honing, chamfers, oiling grooves? ...or do they just drop in?

bww3588

iTrader: (49)

Floating pins are generally splash oiled, some are pressurized using a passage from the rod bearing. But stock rods do not have this.

If you use that piston with a .943 pin, you will have to have bronze bushings put in the small end of the rod.

I ran into this problem as well, and after some searching I decided the price to have the stock rods bushed, quickly eclipsed the price of a set of forged aftermarket rods with a .927 pin. Which opened up a whole new array of piston options.

I paid 294 shipped to my door for a set of stock length scat rods from ws6store.com.

ckpitt55

iTrader: (4)

this build is starting to snowball out of control lol. out of curiosity what were you quoted to bush the rods?

bww3588

iTrader: (49)

250. This also included resizing the big end for the arp bolts, which you will need to have done as well.

I figured for another 50 bucks I'll have a forged rod, with better arp 2000 series bolts that will work with better piston options.

bww3588

iTrader: (49)

The reason I was quoted so much is that it included the price of the bushings...which was not cheap either.

bww3588

iTrader: (49)

I had the same snowball problem. I went from just fixing what went wrong on the ls1 to a 370 with an ls3 top end. I could have had my car on the road a year ago, but good deals kept coming up. Couldn't resist.

bww3588

iTrader: (49)

Also, one other thing. You may already know this, but if you change your pistons, you will need to have your rotating assembly balanced.

ckpitt55

iTrader: (4)

Yeah I'm aware. Upon teardown of the motor, the original crank had a casting defect on one of the main journals, so I returned it for another one - would have needed a rebalance even if I could've reused the stock pistons.

I'm also installing ARP mains and head studs. So I'd need balancing, align hone, and torque plate hone, in addition to whatever rod work if I were to use the stockers. Unless I get crafty and machine some bushings up and press them in myself. That's playing with fire though. Damn at this point I'm a crankshaft away from building a stroker motor.

bww3588

iTrader: (49)

I tumbled with the thought of stroking mine as well, but I decided against it. Once you go big, it's hard to go bigger once you get tired of it. Well, hard on your wallet anyways. I settled on the 370 for now as it will give me a decent bit of power over the 346, and have better street manners. Later on, I can stroke it and re use the block and top end. Just change the rotating assembly and cam.

bww3588

iTrader: (49)

And in my opinion, if your going to stick with an ls1 block, don't **** around with stroker crank. The power you will gain is not as stellar as most think. The small bore really limits it.

thompson

iTrader: (4)

^^^agree with above, Go forged piston and rod. If you do not have access to a rod hone you will be paying to fit a rod to the pin and after all the work will end up paying for an an after market rod but still have the stock one. We do forged piston on stock rods but have a full machine shop that does not make it cost prohibitive. You can go forged piston and rod for so little money that it is really the best way to go.
That being said if the block is damaged and needs a line hone, you need a crank and are looking at pistons and rods you will have a lot of $ tied up in the block when you can just buy a motor outright from someone like us with the forged pistons and rods all ready in the motor for as little as $2499. You can also go forged piston only for as little as $1999. This route you don't have to worry about ANYTHING just putting the motor in.

ckpitt55

iTrader: (4)

I came to the same conclusion after seeing guys post similar numbers with little more than a cam and associated bolt ons. Part of me still thinks it'd be cool though.

Seems to be a much bigger $$$$ investment to bring out the full potential of those additional cubes.

bww3588

iTrader: (49)

What really turns me off about the 383, is I see similar numbers out of 370's and 376's...without the added cost of cranks, rods...etc. there are cam only ls3's putting 500 at the ground...

ckpitt55

iTrader: (4)

Seems as though a forged rod is a no-brainer. Thanks for your comments.

The block isn't "damaged" per se - I installed ARP main studs and the main bores were distorted out of round. This of course is assuming that anything greater than 0.0001" o-o-R on mains is unacceptable. In my worst spots I'm around 0.0002-0.0003". Might be OK, might not be. I've searched but haven't seen anyone comment on what's allowable. But it's gotta go to the shop anyway to have the cylinder bores honed, so I'm going to have them check it.

Also already have a new crank. The one I pulled out of the motor had journal damage - the vendor I bought the motor from replaced it for free.

And also to address your last point - I'm in no hurry to get this thing done. I want to take my time and build it myself - to me at this point the learning experience is worth the additional wait.

A_VAS

iTrader: (16)

Autotec has 2 piston p/n that will fit the bill for you, .945 pin
1000587 or 1000588
these are ~10:1 w/ 4cc reliefs

otherwise I've been down this road before as well, and kinda wished I would have just bought a cheap set of forged rods. Usually they aren't as cheap as you think though also by the time you have them resized and/or pin fit if the clearances aren't right

bww3588

iTrader: (49)

294 shipped is pretty cheap in my book...