Tad

Just curious.
Lets say I wanted to throw JUST rods into an engine (specs below) .
Could I skip all the hassle and leave the engine installed in the car, drop the oil pan, and reuse the same pistons/rings??
Basically no honing or real rebuilding or anything?

reason is I'm planning a sohc forced induction build, and want to be able to handle more power but save time/money.
From what I hear RODS are the first part to go when you start breaking 300whp. So why spend all the effort replacing things that won't break anyways?
Also what kind of whp do stock pistons tend to be able to handle? I'm guessing a lot?
My target is 500whp, but i'm guessing 400whp is more realistic.

Planned project, either dseries, or LS engine. stock head.
inexpensive turbo running as much psi as is efficient.

JRCivic1

The pistons do not come out of the bottom of the engine... only the top. Since you cannot access the piston wrist pin in the engine, the rod/piston combo must be removed to further dis-assemble it. Sorry... not as easy as you had hoped.

Neither power target is safe with stock pistons... nor a stock sleeved block. It is incredibly rare for a SOHC shortblock to survive that level of power. Prepare to do pistons and block fortification.

Tad

Iiiinnteresting. Ok yeah a quick google search let me know about the top install..
pulling the head isn't really that big of a deal. Not having to hone or machine things is what i'm aiming for (ie avoiding the machineshop entirely).
I have rebuilt engines in shop class so it's not totally alien to me.

About power levels.
From what i've heard from other sohc FI guys, is that totally stock sohc longblocks can take around 250whp reasonably with proper tuning.
and i've even heard of some getting close to 300whp.. idk how long those 300whp ones lasted, but at least a couple ran for a noteable ammount of time.

And then there's the LS engine which i'm also looking at. I've "heard" those can break 300whp on the stock longblock with good tuning..

maybe i'm totally wrong though.

turbomaniac

Its possible and piston - rod can come out from below (if there is no piston end circle). But since you have gone so far its not that difficult to slacken a few more bolts and take out the entire engine block.

2kdrift

Even when doing the top install honing is still recomended
watch this one B series motors can handle a bit more power since they have thicker rods, as far as a d16 anything over 250 isnt considered safe due to the skinnier rods

boosted94gsr

I was gonna post that video lol.

Tad

Oh yeah if i was putting in new pistons/rings i'd for sure have to hone it. from what i've heard in that case you kinda need a real machining ? but idk.

what i'm wondering, can you just put new rods on the old pistons/rings, then the walls shouldn't need honing?
i mean you're basically just taking the same stuff out then putting it right back in right?

Tad

Oh of course, that's the reason for my whole post.
if I want to make over 250, people always say the rods are too skinny.
so why not just swap out only the rods

2x0

Because the pistons will fail not long after the rods. Honda uses the same factor of safety when designing all of the internals, so yeah while the rods may be the first thing people break, the pistons won’t be reliable for more than 250whp either.

Don’t waste your time cutting corners here. You have hopes for high HP. Pull the engine, and build it properly. You’ll save time and money in the long run.

boosted94gsr

OEM Honda pistons are designed for press fit pins not floating pins like after market forged rods use. So if you are upgrading to forged rods you need to get pistons that are designed for floating wrist pins as well. Honestly your best “cheap” option is to get ycp vitara pistons with speedfactory forged rods to raise the compression a bit. Or if the engine is healthy just work on getting a functioning turbo setup on the stock motor. I’m sure you’ll find out really quickly you will run into enough problems with just the turbo setup alone without even opening the motor. Especially if this is your first turbo build.

Tad

I didn't know that. kind of throws my whole idea out the window then doesn't it. haha.
I've run a 200hp JRSC sohc before stock longblock.
I really have no need for anything under 250whp at this point.
Following the old style of making things "better and better" as time goes on is really unnecessary in my opinion.
why reinvent the wheel? Why start with parts that I know i'll replace eventually?

The vitara idea sounds intriguing.
what kind of whp do vitara pistons handle?

Tad

that's what I wanted to know, at what point do the pistons actually fail? no one seems to know this.
I don't really believe in common knowledge when it comes to tuning. It's fine to play it safe.
But I don't like to reinvent the wheel.
I've seen enough guys making 250whp sohcT on stock longblocks to know theres more durability in there than people think..

I'm guessing 250 is the safezone for rods, but pistons probably much higher because they fail due to detonation more than overpowering.
I mean, how often do you hear of pistons breaking on perfectly tuned setups where nothing goes wrong and it's just too much power?
Ringlands I guess.. but even then...

JRCivic1

200 WHP on a JRSC SOHC engine ??? WOW !!! That is strong... do you have a dyno graph showing this ??? I would love to see it.

2kdrift

lets assume you are correct which i dont agree with, where will you find an aftermarket rod designed for a pressed fit wristpin?

I mean either keep it safe (under 200HP) or build it properly

Tad

no no i said 200hp, not whp, haha.
200whp was my goal but i only it about 180whp, which was still pretty good

JRCivic1

Yeah, 180 HP at the tires is still pretty stout for a "single-jingle"... well done.

Tad

thanks bud! it really was a nice setup. sounded good too :D

GoldieWang

This! I have had my fair share of hang ups doing my first hands on turbo build. I have learned a great deal too though.

Tad

naahhh turbo systems are pretty easy for me.
i've put one together before and did full jrsc build before as well..