SaM DA Man

So I'm planning on boosting my DA but first im gonna rebuild the motor. It's not doing to to healthy. I've found a guy on craigslist selling some je srp forged pistons mated to pr4 rods. He states that they are standard bore and stock compression. So i went on SRP's site to look into these pistons and the pistons that were around the same compression that he mentioned were rated V which says accepts nitrous not T which says accepts turbo or nitrous. I was just wonderinf if this was just dependant on the compression ratio itself as i do plan on boosting. SRP's site i was referring to...

http://www.jepistons.com/pdf/2006-sportcomp4.pdf

And my other question is that since im rebuilding im going to need to get my blocked machined. Ive never had this done before. I know people usually get an overbore of .10 or .20. Would i need to do this with my b18a1 with 200k miles? Or could they just hone the cylinder walls and call it good?

b18sihatch

what i recomend dont get pistons that are mated to stock rods!

you have the block apart you want to replace every part thats stock with a forged part (with exception of crankshaft)

you will have some people disagree with me however. replacing your pistons will not help the integrity of your block, your rods will limit you on PSI pressures and eventually snap under too much PSI.

boring will depend on how your cylinder walls look (scratches,scoring,ect) overboring isnt needed untill you get into shitty walls, and IMO if you are going turbo and you start thinning out the cylinder walls thats only looking for trouble and crack a cylinder walls

also overboring is to increase the bore of the block to increase the blocks displacement. with a turbo that is your displacement, you will make enough torque with your turbo alone small .020 wont effect power much, but will thin out the cylinder walls

i would just get the crankshaft micropolished,block honed (if its ok) then go from there, but definitly get good bearings,good pistons and good rods, that will help the overall integrity in strength,power, and psi

Everyones Hero

I believe the difference between turbo & non-turbo pistons is that one is dished & the other is domed. I think the turbo is dished.

If the motor has 200k on it I'd get the cylinders bored over just to be sure that you have perfectly round cylinders.

b18sihatch

yes he is correct domed pistons are for NA and dished pistons are for FI..

and he also makes another correct point to ensure the pistons are perfectly round.

however you can always pick up a newer block with lower miles for cheap to build

SaM DA Man

Man thats some awesome information. About the forged pistons on stock rods...keep in mind that im not trying to go for some crazy build. I'm aiming for 250-300whp. I just want something that i can daily drive and at the same time have some fun on the streets. If anything

My other option was going stock ls turbo. My friend has a bone stock ls making around 260whp at 12.5psi. If anything, i see there is atleast an advantage to using forged pistons as apposed to stock pistons in a stock ls motor. So would forged pistons on stock rods really be a bad idea in my set up?

Do you happen to know some average prices for the machine work you mentioned? Micropolished crank and block honed? Should i stick with OEM bearings? And should i get ARP studs?

Sorry for so many questions....i just wanna get off on the right food. Thanks!

Everyones Hero

I think my machiene work came out to around $800.

That was boring, decking, micro-polishing the crank, balancing the rotating assembly, ect.

lightcrx

wow that the most ive seen paid for machine work, that would cost about 350 tops over here
bore, hot tank. hone $80
micropolish crank and balance(crank,rods,pistons) $150
decking probley $50
im not arguing with you just curious
what else did you have done?

-joseph

Everyones Hero

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by lightcrx &raquo;</TD></TR><TR><TD CLASS="quote">wow that the most ive seen paid for machine work, that would cost about 350 tops over here
bore, hot tank. hone $80
micropolish crank and balance(crank,rods,pistons) $150
decking probley $50
im not arguing with you just curious
what else did you have done?

-joseph</TD></TR></TABLE>

I pretty much had everything done. Everything you mentioned, plus the rings, having the bearing clearances checked, & all assembly.

The guy that did all of my machiene work is the same guy that builds all of Mike Hunt's motors (local guy reccomended him).

Then I had the local guy do all of the assmebly, minus the head/timing belt.

b18sihatch

keep in mind, its boost! its addicting, you want more and more and more

and keep in mind also rods arent much more than 200.00 and

with low compression pistons you will be able to push as much psi as you want

the power to money ratio is so much better with aftermarket rods.

also getting aftermarket rods will allow you to consistantly change your goals, and wont keep you limited

Pullig

Get some eagle rods they are the best bang for the buck .. My Buddy is making over 300 whp in his d series with eagle rods and SRPs .. I would also get the .5mm overbore pistons

b18sihatch

IMO i would spluge on pistons, get like JE,CRP or some higher end brand

and go with a so so rod, eagle is the best for the price

like i said ive had pistons .020over and its honestly not worth it. esp when you are going for a decent ammount of boost, the thinner walls could hurt you

if you go with a low compression piston and a eagle rod set, you will have a block that could possibly take 400whp plus

thinning out walls even tho its a little bit, is still making the cylinder walls thinner, i would never do that for a boost application

Pullig

do you even know how much bigger .020 is? its .5mm def. not enough to even notice... its thinner then the thickness of your fingernail

b18sihatch

doesnt matter to me, if it were a sleeved block and you were going from 81mm to 85mm it would be a different story, as the ductile iron sleeves wouldnt sacrafice integrity for bore matters..


if it were me, i just wouldnt do it reguardless

SaM DA Man

Not to be difficult or anything but the question still remains. Is there anything wrong with running forged pistons on stock rods. I kinda wanna start out with a budget build...i will later on get forged h-beams...but for 250-300hp will this set up work for now? My friend was telling me something about forged pistons weighing more than stock pistons so if used on a stock rod it can increase the chance of breaking a rod.

I know, i know...honda-tech's go big or go home attitude but i'm just looking a good bang for the buck until i can move on to something bigger.

B18C Turbo

buy my ross pistons they are new and cheap! Pm'ed!

Bjorn20

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by b18sihatch &raquo;</TD></TR><TR><TD CLASS="quote">yes he is correct domed pistons are for NA and dished pistons are for FI..

and he also makes another correct point to ensure the pistons are perfectly round.

however you can always pick up a newer block with lower miles for cheap to build</TD></TR></TABLE>

so... what the hell are flat top pistons good with?

Pullig

why waste your time running the stock rods with boost? just replace them do you wanna spend 300 bucks now for rods and have a good block or wait till later then you gotta buy 300 dollar rods and a whole new block cause you slung a rod thru it.

b18sihatch

well here is the thing.

i once built a sohc motor for NA and the pistons were 10:5:1 and they were flat top.

Forced induction pistons will be dished.

nad high compression pistons will be domed.

it depends on the brand,compression as to what and how they will react to boosting

i was also going to run turbo with the na block however couldnt get the motor to run right after HG blew