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-   -   Upgrading Pistons but not rods? (

Krmnnghia 08-31-2005 04:19 AM

Upgrading Pistons but not rods?
The Car I am buying had toasted pistons but perfect Rods so the dealer I am buying it from had new JE pistons installed on the stock rods, Polished the crank and did some head work. Even though the Pistons are stronger am I to assume the internals are still basically stock strength due to having the stock rods. I am guessing this is the EJ20's weak point?

I know, I know...why in the hell wouldn't you replace the Rods too...Dealer didn't think about that I guess.


Krmnnghia 09-01-2005 06:50 PM

Anyone have any advice/info on this?

jwtarbaj 09-01-2005 10:42 PM

Yep the rods are still your weak point. They will need to be upgraded before you try and produce crazy power. IDK how much they are good for stock though.

knot04 09-02-2005 12:17 PM

tada stroker kit!!!!! $3180.

hondaeater 09-05-2005 05:19 PM

IIRC the stock rods are good up to about 400WHP, pistons to about 300WHP.

dunham 11-20-2005 11:46 PM

they should have replaced rods while they were in there. Each rod wears differently where it connects to the crank and the wrist pin on the piston. New pistons with old rods (especially rods from blown pistons) will cause wear. Dont push your hp too high before checking on the condition of those rods. make sure your rods are still in manufacturers specs for oil clearance.

stileguy 11-21-2005 08:22 PM

450-500hp at the crank will be fine if you have a good tune without raising your rev limit. the stockers are quite strong, if you get detonation it may hammer the bigend to the point where it locks the rod onto the crank resulting a big mess, the main weak point is the big end fasteners, they fail when you raise the rev limit. if you keep the rev limit to the stock level and are sensible with the amount of timing advance you use then your motor will be fine with boost levels to 25psi. if they replaced big end bearings you will be fine. if the same bigends are in the engine as when the pistons let go then you may have problems.
why did it blow a piston? this is more important than the integrity of your engine, if the same engine management is being used you will blow another engine regardless of forged pistons.

04roadtuned 01-29-2006 10:55 PM

ill tell you why the dealer didnt replace the rods
A: they were ok
B: stealerships are cheap and only spend what is necessary and nothing more. NOTHING MORE

04roadtuned 01-29-2006 10:57 PM

[QUOTE=hondaeater]IIRC the stock rods are good up to about 400WHP, pistons to about 300WHP.[/QUOTE]

does this mean you can change rods and pistons, and not have to resleeve the block to achieve lets say 450whp. and raise the rev limit with a little crank work and an upgraded valvetrain?

trek98xc 01-29-2006 11:12 PM

if youre going in there you may as well do it all at one time. if you want to go all out get a stroker kit.

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