What is the compression ratios on our cars?

 

8.1:1

 

I am thinking of buying new pistons and rods, and i was wondering what ones I should go with. I saw some thet the compression was 8.0:1 and some that were 8.5:1 What would be the benefit of raising or dropping the compression and where can I get good pistons and rods for a decent price. Is there any onther mods I should get or do while I have the motor torn apart?

 

I also was on the modernperformance website and saw this. Is this anti friction coating any good? Would it be worth me buying.
And When I buy new rods and pistons what will that allow me to do? Can i run higher boost on pump? Nitrous?
http://www.modernperformance.com/pro...oducts_id=1711

 

The lower compression you have, the higher boost you'll be able to run on pump. Lower compression pistons are good for when you want to make lots of power on pump gas. The lowest compression piston I've seen for our car is 6.9 at Rage Tech.
If u have higher compression pistons, you'll be able to make serious power on low boost and lots of power with race gas.

If it were me, I'd upgrade the head, cams etc. if I'm upgrading the bottom end. Obviously that's lots of money.

Crower rods can take a beating. They cost a bit more but they're more durable.

 

What would be my best choice? lowering or raising the compression? What brand of pistons? I will be upgrading the head soon but probably not right now. I have read something about upgrading the oil pick up tube? Should I be doing that and what is a windage tray? Also I was reading about srt4's removing their balance shafts... What is a balance shaft and how does it benefit by removing it.... Thanks

 

wow you have alot of questions lol....which pistons you get really depends on what route you want to go with the car...assuming you will be running pump gas all the time i would think more lower compression like lblackneon said.....of course you can possibly make the same power with the other pistons at lower boost...so idk its a toss up...its up to you....modern performance used to give a description of what that windage tray does but I forgot already...sounded pretty handy though...more like maintainence part than a perf part if I remember correctly...

 

yes i do have alot of question... I happen to have to rebuild my motor due to me blowing it up again... so i figur while I am in there handle everything that needs to be delt with. I am still unsure of if I should raise or lower the compression and if there are other mods I should take care of while I am in there. I would rather take care of all the internals at one time as opposed to take it apaprt a second time. Any opinions will be considered. I would like to hear everyones view before I make my decision... Thanks

 

ah ok, i was wondering why you were asking about building the motor lol. how the hell did you blow it AGAIN?????

most people go for the weisco 8.8 pistons .20 over. that's what i'm actually planning on doing over the winter. that and a set of eagle rods. and geta new bearing kit. i would also suggest a dcr tensioner, the stock one is junk. don't forget cams, gears and a pnp head too.

the windage tray basically keeps the oil from the crank. it's a way to free up hp. the balance shafts are exactly that, the balance the motor a little better. they are not necessary to have, and really their major function is to reduce noise and smooth out the ride. the oil pick up and what whole oil kit that dcr sells is a waste of money. it's completly over priced and not necessary. the only thing that you need to upgrade would be to get the oil pump from dcr, that definetly is worth it. remember too that if you go with a windage tray and remove the balance shafts you're looking at a 7 quart fill.

if you're going to build the motor take it to a local shop that you know does good work and have them do it. i spoke to ripp mods here and they're going to build my motor and install it. the whole build and installation is going to cost me the same (actually a little less if you include shipping) than buying a motor from dcr would run me (not including install). it's the same damn thing too. i love the guys at dcr, but they are WAY overpriced.

 

to be honest i was running from the fuzz at 160 plus.... same way I broke it last time. But the first motor I only broke the tone ring. this time i broke my first and forth rods and and damaged a few valves apparently. The shop I am going to told me he has not had anything good with raising or lowereing the compression he tells me to leave the compression stock.and that sounds lame. If I am going to build the internals I dont want them to be the same as a stock srt4.PSICHICK how are you going to benefit from raising it 8.8:1. what does that do for you/what does it enable you to do? and what does .20 over mean and how does that benefit you? How much is your setup going to run ya?