I am planning on building a 350 gen1. I have a block and will be buying the crank, harmonic balancer, rods, pistons, piston rings, and all the bearings. So I have 3 questions.

1. When I buy the 2 piece internally balanced lightened eagle speciality cast steel crankshaft will I need to take my harmonic balancer, crank and flywheel into the machine shop and have them balance it or am I good to go?

2. Do I buy an internally balanced harmonic balancer since my crank is?

3. And if I am buying scat I beam forged 4340 steel rods that are floating and buy forged SRS probe pistons that can be floating or pressed fit do they come with the floating wrist pins or do I have to buy that? Because floating is what I want to go with.

TIA

 

1. Absolutely not!! Have the rotating assy balanced RIGHT, then LATER (or EARLIER as the case may be), have the external parts balanced RIGHT. THe problem with taking them both into the shop at the same time is, the temptation for the spin jockey to "balance" the final product by leaving the crank wobbly and "balancing" it by hacking on the externals, is too great to resist; and what you'll end up with is, "custom" "balanced" parts that no longer interchangewith anything else. This is totally unnecessary. Don't let it happen to YOU. Keep your engine serviceable on down the road by making sure that those parts are NEVER EVER in the same shop at the same time, NO MATTER how hard they try to sell you on the idea that they "have to" have them all together. They don't. If they won't give up, take your parts somewhere else.

2. Yes.

3. Wrist pins are the same. The difference is the small end of the rod. If you buy rods that are set up to float, then you have no choice but to float em.

 

Ok thanks. So is it the pistons or rods that the pins come with. Because I am not ordering a rotating assembly, I am ordering the parts individually. And if I buy the crank internally balanced, the harmonic balancer already internally balanced and the flex plate (I have no idea why I said flywheel earlier, I was super tired I guess ) internally balanced all from summit then will I need to take anything to the machine shop?

 

Pins are with the pistons.

 

Yes

 

Ok thanks everyone! I am sure the machine shop will know what I want done when I tell them what I told you guys.

 

1: Yes. Even though the harmonic balancer and flexplate/flywheel are neutrally balanced, they should be taken in with the rest of the rotating assembly to be all balanced together. Even tough they're neutrally balanced, they're not perfectly balanced.

2: Internally balanced crankshafts need a neutrally balanced dampener and flexplate/flywheel

3: Wrist pins come with pistons but you can always buy better wrist pins depending on your application. My pistons came with 0.150" wall wrist pins but I purchased 0.180" wall wrist pins as an upgrade. Tool steel wrist pins would have been better but I didn't need them. As mentioned above, the rods will determine if they're pressed or floating pins.

 

Thanks and that is a bad *** camaro Alky. I'm assuming it has a trans brake?

 

Have you ever even balanced a crankshaft before? never in my life have I ever modified a flexplate or balancer while balancing a crankshaft. You end up having the same issuethat you stated of having balance issues in the future if you ever have the need to change a flexplate/flywheel or balancer. Deal with a reputable shop in the first place and you wont have a problem. On internal balance stuff I balance to the crank to within tolerance (0.02 oz in) without the flexplate and balancer, then install both to make sure it dosnt change. Use quality parts and it dosnt. Use poor quality parts such as professional products etc... it will.

To the OP, since the pistons can be pressed or floating, that means they have provisions for some sort of pic lock. The only deciding factor would be the connecting rod. Since you need to buy both, I would go full floating. Make sure that the shop checks and hone the pin bores of both the rods and pistons as from past experiences, both scat and probe come way to tight out of the box(I have had scat rods as tight as 0.0002"0.0003") I would reccomend 0.0008"-0.0009" pin bore clearance on both.

 

Working as a engine tester at the Tonn,NY engine plant we would run test all the 307,305.350,and 400 engines and as apart of the test cycle final balance to factory spec's(Uggg,not very good factory spec's I might add.) by pounding in balance pins into the H/B'ers. Guys would re-balance their engines for racing applications.So for the early engines those balance pins need to be removed.For that matter,any H/B'er that has the holes for balance pins need to be spun balance with the rest of the assembly.Alot depends on what bob wt is used.

 

Powerglide and a transbrake. You only need to go to my web site to see all the details.