About how much would it cost for a mechanic to swap out my pistons... Sounds kinda expensive...

 

We will be going through this soon with Rob's car I'm sure, so once we have a feel for the amount of time it will take we can get you a good estimate on hours then just multiply that by your base hourly rate for you mechanic.

 

Sweet.

 

They be nice looking.

 

Going from 9.5 to 10.0 CR will give a noticable boost in power concidering that there is no KR. Should also make the engine more snappy in the lower rpms when the boost hasn't kicked in fully.

 

mmmm pistons.......more power i see in the future..... (sorry star wars is on tv)

 

Nice, I can't wait...Another good wkend project...

 

so they are gonna be like a 4 for a dollar deal right? definitely nice pulleys

 

looking good

 

pistons look really good... how much of an issue would they cause if you were running a 10.5:1 and a smaller pulley pushing 17-18psi?

 

sounds crazy ^^^^


and fun

 

this may be a dumb question but usually compression is lowered with boost so will there have to be a lot of tuning to get these to work well with the S/C?

 

Hold on a sec. I thought high compression+boost = BAD. Most FI cars have low compression, like 8.5:1 and lower. Are is unusually high (already at 9.5:1). Mabye its safe for the stock engines which only runs about 12.5psi, but what about others who already have a pulley swap and are boosting 15-17psi? Hold is the rest of the the engine going to respond to this? Also what about the valve clearance? Is there enough? I wouldnt want any valves stabbing through my pistons or even blowing a rod or two. Im all for getting more horsepower and Ive been looking at others companys for forged pistons. I know you get a custom pistons from JE for about $650 U.S. for 4-cylinders. Dont get me wrong Im very interested but I need to know about any practical applications. If alls good this will definately going on my list of things to buy.

 

Well looks like Im not alone on this high compression/FI issue.

 

Does anyone know if our valves overlap?

 

At some point with motor modifications the motor will breath well enough where smaller pullies do not result in a lot of boost (a 2.8 could be pushing say 10lb of boost with a cammed, headed, headered LSJ in the future). Spinning the blower faster is an option but there comes a time where the parasitic loss of the blower is more than the gain from a smaller pulley and at that point higher compression comes into play. The 10.5 will be for those kinds of setups.

The 10.0 is higher than the 9.5 but the thermal and moly coatings on the pistons will allow you to run higher compression without the extra heat associated with it so you can gain performance while having the reliabily of a much stronger forged piston.

 

Daaa, do u tinks itl help stop da wheelhop, hop, hop, hop?! People these days, if you do not know what a piston is by age 10, you should stick to pedal bikes! Daaa, what does a pedal look like? Does it look like da cam?

 

Yes, usually people swap there pistons for lower compression pistons. But Im very curious to see if our motors will be able to handle 10.5:1, along with a 2.8 pulley. Personally I wouldn't push any higher then 10.0:1. That would be ideal for as longs as all your internals are forged. Isnt everything else in the bottom end of the LSJ forged? I mean except for the pistons, right?

 

Oh man this is great news! I've been waiting for this day haha. I hope they are affordable...Anyway, a higher compression motor is going to have far greater torque and low end power as the boost is only starting to come in, vs a lower compression motor that is going to basically relying soley on boost to create power. You don't want to go too high of a compression ratio or the useable boost from a supercharger would almost be negated (that and the effective compression ratio would be way out of the boundaries of a streetable motor). From what I understand you want to have a nice balance between compression ratio and boost while maintaining reliability. But anyway, this is usually the case w/ motors running 8.5:1 compression or lower...the stock compression ratio is fine for the LSJ, but IMHO I think 10.0:1 w/ forged pistons the LSJ would see a nice bump in power while maintaining the same boost level.

 

Glad someone else see's the light besides me!

Think about all those LS1's out there with high compression running turbo and supercharger's making HUGE power! Hell, even the old GN's are migrating towards higher compression with a good amount of boost.

We have no TQ and any way we can increase it and also gain effeciency will be of a GREAT benefit.

The w-body guys are another example, running higher compression with boost. It works, you just need to be in control of whats going via PCM tuning

 

Holy triple post Batman :P

 

Oh dear...

 

Do these pistons do us any good without PCM tuning ?

 

That's what I was wondering... or at least a different tune than kits for stock internals?

 

I want to do some testing before interject some data but i will go on a hunch some form of tuning will be needed to optimize.

Remember, the stock pistons are only good to 300-350 CRANK HP. That is only 255-298 WHP! Depending on who you quote/read it in. So if you get even slightly serious, pistons will be needed.


As for the price to install, we are offering a killer deal on installs at my shop, call me if interested. We are charging warranty time only, NOT book time which is inflated 40-60% over warranty!