just thought I’d ask and see if my rods are up to the task of my planned motor. At the moment they are standard rods in my small journal 327. Motor was originally a 210hp and is going to end up around the 350hp mark. Street driven 90% of the time with the odd go down the strip. Hopefully the rods are up job, as I’m only building this motor once.
My SBC is north of 400 HP so I went with after market rods. I asked the builder about reconditioning my existing rods (ARP bolts, checked, etc..) and the price of a new set of Scat rods was a wash. I believe in doing things only once.
What Bob said. I just change rods every time. You have no way of knowing how many times they have been reconditioned. They are all good until they aren't.......know what I mean? New rods are cheap insurance. https://www.cnc-motorsports.com/scat-2-icr5700-2000-pro-stock-i-beam-connecting-rods-40911.html https://www.cnc-motorsports.com/sir...sb-chevy-283-327-5-700-length-bushed-pin.html
The last small journal small block from the factory, was machined in 1967. That means the newest s.j. rod has over 50 years of compression/tension cycles. Metal does fatigue! At the very least, you should have the rods removed from the pistons(pressed fit) resized, and new ARP bolts installed. Before you send them off to the machine shop, price the above work and parts. I think you will find that for a very few dollars more you can replace them with aftermarket rods. Eagle 5.7 small journal rods can be bought for less than $250. These rods are 5140 forged with 12pt ARP bolts and matched weight. The next step up are Scat 5.7 small journal for less than $300, 4340 forged but with ARP cap screws. Either is available pinned or bushed for full floating and either is good for 500 horsepower. I would not assemble any performance motor with stock rods if there was another option. You stated , you only want to build it once. You will, because when that stock rod comes apart, there won't be anything left to rebuild.
As bobss396 stated above, the cost of reconditioning versus a new set of Scat rods is the way to go. You will have most of the cost of the new ones in reconditioning. New rods versus old rods with an unknown millions of cycles on them. Just looked on Skip White Performance--$279. No brainer. OOPs. Missed the small journal part.
I have the equipment and still do my own. If you have to send them out I'd go for the Scat rods. If I'm going for a lot more than stock HP that is what I do. Pete
Thanks for the quick replies. Looking at the pistons and the fact they’re std size I’d say it’s never been apart. Being in the UK it’s not as cheap or as easy getting these parts. Those $300 rods end up at $400 with shipping costs and import duty. I’ll check out links and see what the prices are.
Had a quick look at Eagle website and it says they’re the same 0.927 press fit. Looks like I’ll get these as they’re rated for up to about 500hp
Those are the ones I have, entry level Scat rods, I went with the floating pin with mine since I was getting new pistons. I'm sure small journal ones are around. I got mine on eBay shipped for $255 in late 2015.
Just bought those Eagle rods from JEGS for $250. Went with these as they’re press fit and will suit the new pistons
It's pretty hard to argue with the price of the OEM style aftermarket rods, never owned any of the offshore versions but I have a set of Callies rods in my OT engine. I have heard some are better than others, if a sizeable amount of money is going into an engine (any engine actually) I'd suggest having the import rods checked by a shop that is willing to put YOUR bearings in them, torque them and check the bearing I.D. (on all eight units). Quality control on mass produced Chinese products has not been consistent. As to factory rods; the 66/67 were much improved over the 62-65 versions, I bought a set of the later rods (NOS) that a Chevy parts man had stocked away for himself but changed his engine plans, I also bought his NOS small journal forged crank. Here is a good photo that shows the difference in the extra material in the 66/67 rods, if a set of used ones can be found they are worth putting money into refreshing them. Discussion here: https://www.corvetteforum.com/forum.../3555171-62-65-327-connecting-rod-defect.html
Thanks for everybody’s thoughts or opinions. Hopefully made a good decision with getting those Eagle rods.
Well I’ve got some parts in. New pistons and rods Off to the envy builder on Monday so he can hone the block to fit. Soon have this engine built up
Good choices and a good builder will look everything over before assembling the pieces. Pistons need to be deburred, cleaned and so on. Rods, all I used to do was take the caps off, look for burrs and stone anything that was a sharp edge.
Luckily I’m the engine builder and I’ll go over everything before I build it up. Only using the machine shop for the boring/honing. Got some 12000 grit aircraft glass polishing material, so I’ll go over the pistons with at that before installation. Also going to weight match the rod/piston assembly
Your new rods appear to be nice and beefy. The photo DDDenny posted shows a 1966, 327 rod. We always used them in any early 2" sbc. We referred to them as a "cloverleaf" rod. I never had any trouble with them.
Maybe I am Lucky my 327/300 has Never been apart, its starting just Recently to have a Little Blow Buy, which I Mite change the ring's or Leave it for somebody else to do When I am Gone. Just my 3.5 cents Live Learn & Die a Fool
I took mine apart to check the notes and such. Found rust marks in a couple of bores. Took the pistons out to find one set of rings totally siezed so took the decision to totally rebuild
Bought some Eagle rods. The last thing I want to do is have any problems later down the line. I’ll be putting about an extra 150bhp through 50 year old rods
Just going to go over the very crown of the piston to make sure I don’t get any nicks in the notes on installation. The 12000 grade won’t affect the piston at all. I got it when I was in the forces. It’s used to polish the aircraft canopy
Looking at those pistons I hope you have really good fuel or very big chamber heads. 327 with 64cc heads and flat top pistons get you 10.5 compression. Trying to run to much compression on pump gas is a big pain.
Those rods will do just fine. I know several guys running them at near 500 HP, and revs to 6000 or so with no problems. Its all in the details , time spent carefully building= happy engine.
Better to be over engineered. Definitely not going to be in a rush with building the engine. Only going to be used as a cruiser with the odd go on the strip. Not pulling much weight either as it’s going in my Model A Coupe
I highly recommend getting the crank balanced as well. There is a good chance the pistons and rods are heavier than stock. Do you have a fixture to hang the rods on when you weigh them? If not don't mess with them. You balance each rod end separately. The upper half is reciprocating weight, and the lower half is rotating weight. On a V8 you use 50% of reciprocating weight and 100% rotating weight to make a bob weight and balance the crank.
I’ll have a word with the machinists on Monday. I was only going to match each rod/piston assembly. If they’re all pretty much the same then I’ll leave them alone.
Not sure. Are 461 heads 64cc? I'm with sunbeam's post above. Looking at the dome on that piston makes me think about GM's old 11:1 pistons. I wouldn't take Sealed Pro's valuation of your CR. They don't know all the variables in the 7 or 8 variable equation. There are many online calculators for CR. Try Wallace Racing Calculators. It's a pretty good one. I don't know your gas situation, but you couldn't get away with that combination here. The rule of thumb is 9.5:1 max for iron heads around here with pump gas, but then the best pump gas here is usually 93. What is your deck height? CC of heads and piston dome? Bore and thickness of head gasket? Find the answers to these questions and you can figure your own CR precisely. Quench distance? A good tight quench, .035" to .045" will help ward off detonation in a higher compression engine.
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