planning a 355
stock crank, worked over, polished, lightened etc.

rods, 6.00" Eagle H-beams (unless someone recommends a better rod for about the same price) should i opt for the L19 rod bolts or would the 2000's be sufficient? i plan on spinning it too about 6700rpm

pistons, i was looking at Keith Black forged aluminum pistons, 30 over
for the price of about $390, it sounds like a deal too me
whats people opinions on those? they have too better then hypereutectic....?

will be balanced together with stock flywheel

i have ideas of nitrous on top of it
i figure if the stock bottom can handle a controlled 100 shot "reliably" that the above mentioned rotating assembly should be able too handle ~200 shot pretty easily?

another question i have is how do you go about matching the piston pin too the rod you'll be using or vice versa (size, floating, bushed)? from what i have been looking at, they arent all the same...some rods havent different little end diameters etc. and same goes for the pistons

does using a 6" rod affect the piston choice, especially if a power adder is thrown into the mix?
what if there is no power adder but i would like too stay at about my 12:1cr, does that affect piston choice and rod length?
will the 6" rod automatically move the wrist pin farther into the oil ring?
now how does block deck height affect my choice of rotating parts?

i plan too reuse my heads (52cc) and cam until i purchase a nitrous grind for fun later on but i dont want too tear the motor down again/later because i didnt put quality parts into that will withstand an above average (175+) nitrous hit


fyi, it is a street car with alot of track use (nitrous would be track only)

Steve
(hoping someone will break the post down and answer all questions)

 

I like the stock crank but why go with rods that are overkill then rod bolts that are even more overkill and hard to handle to boot.... If it was me I would look at a good I beam forged rod like a Eagle SiR or a Scat I and call it a day. In this situation your rod choice is WAY stronger than the crank, doesn't make much sense to me.

I also don't understand this.... $540 rods and $390 pistons? I would do that the other way around, you are not going to over do the I beams, and the pistons and how they seal and take detonation, N2O, lean conditions and seal the combustion process of is a much better place to spend money.

I personally like Mahle pistons for this. They have a piston and ring kit that runs in line or cheaper than a SRP piston set and rings. They are a little narrower and they are matched to the pistons. Last set of SRP's and rings I had that came as a set I had to lap a ton of the rings for proper side clearance with the rings and pistons, didn't make me happy and I will never use that brand of rings again.

[QUOTE=simple]will be balanced together with stock flywheel

i have ideas of nitrous on top of it
i figure if the stock bottom can handle a controlled 100 shot "reliably" that the above mentioned rotating assembly should be able too handle ~200 shot pretty easily?

With good pistons, yeah. It will take it.... I usually neutral balance the flywheel then neutral balance the whole motor assembly.

Almost all SBC rods have a .927" pin size.... Definately get bushed rods, going with press fit rods is a pain in the ***.

You should get pistons with Pin fit... to fit the rods to the pins you need a hone or have a machine shop check them all on a Sunnen Bore guage and size them all correctly. I find 1-2 rods in a set of forgein rods need this to be done with some big ends needing to be corrected as well.

Yes.... You start off on a LT1 block with about a 9.030" deck height...

The average SBC 355 setup will put you at a 9.000" - 8.990" deck height so the piston will be down in the hole if you do not deck the block, which you should do.

When you keep the same stroke, and change the rod length the compression height of the piston changes. This doesn't change compression, the valve relief or dish volume changes compression along with the deck height of the block and the volume contained in there.

Make sure you get good pistons in there, you are more likely to screw up pistons with N2O than other parts.

If you want to go overkill.... Eagle H Beams with the standard rod bolts, Mahle Piston/Rings, stock crank and 4 bolt the bottom end. Other than that a 2 bolt stud setup, Forged I beams and Mahle Piston/Ring kit would work awesome.


That help?

Bret

 

This buildup sounds very similar to one I have planned as well. Bret and i have discussed this as well, and my mind is made. I am going with the stock crank, Eagle i beams, and the Mahle pistons and rings. On top will be the LE2 heads/Cam...and some spray. I am confident that it will hold that just fine, and is very easy on the pocket buildup. Oh, and I am just gonna stud the 2 bolt bottom end.

 

thanks Bret, definately sheds light in my not so bright noggin
if i thought i knew what i was doing by piecing together a bottom end, i wouldnt have made a post about it here hoping for an experienced answer (yes, i know which folks too listen to on here)

the reason i was gonna go with those rods was because of RPM and HP ratings according too their website (and they are cheaper then comparable rods). they fit into the plans better then other h-beams do from what i have gathered. i do understand what you are saying about them on top of the stock crank tho.

from what you know, what are the limitations of the stock crank with proper machine work done too it and a competently balanced assembly?

makes sense too me so far