zcar03

iTrader: (7)

So Im considering doing a rebuild before a blow my motor and render it useless. I think that I need just pistons and rods but am uncertain. Everyone I spoke to says no need to mess with the heads. How much am I looking at in parts only for a set of pistons and rods. And what brand is good and compression. I may boost the motor more if I build the motor say up to 15psi. Thanks!

350Z400rwhp

iTrader: (4)

You should be safe at 12 with a good tune on the stock block. Do you have all the basics like injectors, 1 step colder spark plugs a fuel pump and a good tune/tuner? The issue with "just doing rods and pistons" is that you are taking the whole motor apart and you might as well upgrade the head gaskets and other things since you are already tearing everything down. I'm not sure how efficient the procharger is past 12 psi but other members on here have push to I think as high as 17 with a build motor (JayZ)

thom000001

/\/\/\

Yup, If you're going that far anyway might as well do everything. ACL bearings, HG gasket, L19's, etc....or if you plan to stay under 600rwhp or so (forever) you could do the HR HG's and studs too.
If its in your budget, do cams as well.

These motors are very LABOR INTENSIVE, you do not want to have to go back in and work on the motor again if you don't have too.....

Tom

str8dum1

iTrader: (11)

you should more concerned on how you are going to boost and not break belts.

350Z400rwhp

iTrader: (4)

+1 I think AAM makes a brace but I'm sure breaking belts will still be an issue. If I were you, just enjoy 12 psi on your stock block, sell it when you are ready to build your motor and get a turbo kit. Too many heat/belt issues with these superchargers and high boost applications. Sure you can do it but it's kind of like polishing a terd.

IIQuickSilverII

iTrader: (13)

not much... most combos of pistons/rods are sufficient for most builds so go with cost efficient option.... yeah no need to mess with heads... since they flow well stock... but you can always do cams+springs&shims..not a must though.
DEf do the L19s... not the most expensive item and reusable from the HRs...whcih are cheap anyways.... gasket..cosworth or hr, or hks...

As rich said, id look more into the belts, or a different FI kit al together actually.... if you keep it just do the engine more basic

streetzlegend

iTrader: (2)

My suggestion based on what I have is Wiseco and Eagle H beams, Then since your in there, might as well put in ACL's, thats pretty much it. Then HR gasket and L19's, although HR bolts are probably good to high 500's low 600's.

GBoger

13:1 pistons mang.

zcar03

iTrader: (7)

The tuner said that once I get over 425ish whp that theres good chances my rod will go so idk if I should just throw the 9lb pulleys on and get it tuned or what. I plan on going with 650cc injectors, aam fuel return, hpx MAF and a Cobb port.....

GT-ER

iTrader: (4)

Honestly, get 800cc injectors.

zcar03

iTrader: (7)

800 seems high the tuners I talked to said 600-650 talked to ballistic motorsports.

bryan@Z1

iTrader: (23)

We've had great success with Eagle & Wiseco in the bottom end, go back with ACL Race series bearings rather than OEM. If you do the HR head gaskets you'll need to have the block machined to accept them, we're doing all of our new stage 2 shortblock builds this way. If you don't go that route any performance head gasket (Cometic, Tomei, HKS, etc) will do the trick.

How high you do plan to push the boost is the factor in what CR piston to use. With the concerns about belt life and loss of efficiency at high boost it might be best to go back with a stock or slightly higher compression (11.0:1) piston and make more power at lower boost, and with the upgraded rods and pistons you can push it further than stock with regards to both boost and timing assuming that the fuel system can support it.

GT-ER

iTrader: (4)

You'll want more later, thus why you should get 800's...lol.

zcar03

iTrader: (7)

What tuning should I use? COBB,UTEC, OR OSIRIS. Im leaning to cobb

binder

iTrader: (8)

for a turbo engine. s/c puts more strain and requires way more fuel.

800cc DW's were done at 451hp on my car with a s/c. almost 100hp lower than what a turbo would put out for that same fuel.

You might make it on 600's but you'll be high duty cycle.

425hp on stock block isn't a problem. Torque is hwat kills a motor, not hp. If a tuner told you xxx hp will blow the engine then don't let him tune your car. They should know that tq is what causes stress so tune to a safe tq range. The only reason 425 will kill your engine is if there is a defect in the engine to begin with or the tuner screws it up.