350 groundpounder

iTrader: (5)

Just trying to get an idea for a few years down the road how much the shortblock needs built up to handle 350-380rwhp reliably? Is the stock pistons, rods, and crank up to the job if arp rod bolts are used? Any parts that should be upgraded? Budget minded of course.

VoyagerCamaro

Personally speaking, on my motor only stock internal part I am using is stock crank... Just 10/10 under, but other than that Ohio crank makes a very nice set of forged H beam rods for a great price. They come with ARP hardware too. From what I understand the weak point on LT1s when pushing more than stock power are the rods, especially if you over strengthen the rod bolts with ARP. As far as pistons... I'm not sure. But why risk it when you can pick up a set of Speed pro forged pistons for high compression and reliability/power/strength? I'm using factory heads and my build came out to 11:7:1 with the speed pro forged pistons. Your question can go a long way. Are you staying N/A or are you gonna use spray or build a boosted build? More info would be helpful. I assume your staying N/A if looking for 380-400 hp. I believe my motor is only slightly over 400hp. You can check out my build list in this thread here. https://ls1tech.com/forums/lt1-lt4-modifications/1801213-who-knows-if.html since then I have purchased some quality .80mm thick chromoly pushrods by TFS.

Shownomercy

iTrader: (1)

If you do not plan on spraying/boosting, do not replace quality lightweight Mahle's with crappy, heavy speed pros.

ahritchie

iTrader: (1)

I don't think you really need a "built" short block for that kind of HP unless you plan on spinning it over 6400 RPM. Even then just ARP rod bolts should be sufficient. Better off to spend money on heads/cam when LT1's are dirt cheap anyway if you blow it up

350 groundpounder

iTrader: (5)

Yeah plan is le1 heads and mild cam. No forced induction. So just arp rod bolts and stronger rods? New oil pump.

bowtienut

iTrader: (1)

No, you don't need stronger rods. ARP bolts and re-sizing the big ends of the stock rods will easily get you to your 380 rwhp goal. You shouldn't need to spin past 6500 to get that. Mine produced 425 SAE through an A4 at 6400 rpm.
However, depending on your machining resources, it might make sense to just buy new rods instead of resizing your stock rods.
A new stock oil pump would be best.

Catmaigne

iTrader: (6)

The only reason you'd resize stock rods w/ARPs over buying aftermarket ones is that you won't have to rebalance the rotating assembly.

To make 350-380rwhp reliably depends more on your cam choice. ARPs are unnecessary with a baby cam. You can meet that power goal with tons of reliability with h/c on a stock shortblock.