Compression

[jasonh_86]

What is the compression in a stock '02 GT motor? and how do u reduce the compression?

 

[03ghoststang]

it should be 9.4 - 9.6 cant really remember but get a deeper dish to lower the compression ratio

 

[jasonh_86]

so, to lower the compression to 8.1 u just get dished pistons and the forged internals to go with them?

 

[DBMSTNG]

change the pistons or get a thicker headgasket. you could also get your heads worked on to lower compression, but i wouldn't advise it.

 

[03ghoststang]

are you going FI because if you are then yeah lower your CR but if not i dont really see why?

 

[sgarlic]

The answer to your first question is 9.4:1.

I'm curious as to why you'd want to lower your compression ratio? If you have a pigning problem, use better gas or change cams.

 

[RedGTvert]

Even with FI, there is absolutely no reason to go with 8.0:1, unless you are putting a big thumper on there.

Stick with 9.0:1 and you'll be fine under most FI applications.

 

[03ghoststang]

yeah thats true stick with 9.0..........aint the 03 cobra C/R 9.0:1

 

[jasonh_86]

I was just wondering, because I thought I read somewhere that for a TT setup or KB 2.2 that it'd help to get lower compression to keep the motor from going BOOM!.. But maybe i'm wrong, i'm no genius haha

 

[03ghoststang]

you can keep the stock compresion but just swap out the internals with forged internals and once you add what ever poweradder just get a real good tune and you'll be ok

 

[jasonh_86]

alright.. that sounds good to me. I just wondered about it because a buddy of mine who drag races as a hobby said that dished pistons would be best for motors with boost on them, especially turbos..

 

[hotmustang331]

Your consern if you went with a 2.2 KB or TT would be the ENTIRE rotating assembly. The 03 cobra has 8.5-1 C and thats a good idea when you get a big blower like that. Be advised that you going to spend a BUTT LOAD of cash. 5K just for the KB, $3500 for the shortblock, alot of $$$ for the new fuel system, beefing up the car with things such as SFCs, clutch, than you got the tune for the whole thing as well as installation. Over 13K for everything. for the 2.2. WELL over 15 for the TT setup.

There are more things that would be needed before you run slicks at the track, like new tranny, new rear axle, welding torque boxes, roll bar or cage. Its VERY expencive....you should do like me and plan this stuff out and buy things a little at a time.

 

[03ghoststang]

well said take your time and think it through

 

[billfisher]

with today's engine management and intercooler technology it wastes 14% of your power for each point you drop. you just need the real deal. KB seems to have a complete approach. 8.0 is old school.