I have a couple of questions regarding compression and passing certain state tests... As most, if not all of you know, California has some of the strictest laws regarding emissions and vehicles. Several of my friends, and even members on this board have been sent to the State Referee... I was just curious if higher compression would affect the test. I was planning on running a N/A setup which included Jun 3 or Toda B cams and some CTR Pistons. Say my setup was fully installed, and I got pulled over and the officer sent me to state referee, if I removed everything but my pistons, (bottom end), would/could I still pass the test? Are there ways to get around it? I don't want to touch my bottom end, and find out that I won't be able to pass the test at all with aftermarket or OEM pistons.

Thanks in advance,

Chris

 

Anybody???

 

my guess would be no. Maybe you could pull the timing back to compensate for the upped compression though. I really don`t know

 

TTT, help me out here guys!

 

Hi compr will not cause you to fail an emission test as a matter of fact hi compr helps with overall efficentcy(sp) of the motor and may help emissions except for Nox due to the higher combustion temps but in general it won't hurt and unless its like 12 or 13-1 it won't be that audible when idling.

 

I don't know if compression has that much of an effect on emissions. If you return EVERYTHING back to stock, except the pistons, i'm guessing you would have a pretty good chance. If not, you can always get thicker head gaskets to lower your compression. I'm not sure if this is related or not, but the Celica GTS has 11.5:01 compression and thats STOCK.

 

yeah generally speaking your NOx readings may increase with higher compression, that is about all that could happen. Its really hard to predict what may happend in each case. I do know some guys that corrected that by increasing fuel pressure a bit, and others have retarded timing heavily to pass emmissions. I would think you should be fine though. good luck.

Joey

 

Its all about tuning

 

SCC magazine had an article about creating a good competition car and that also pass emissions , and Jun had an SI that was fully built N/A that pass emissions ...
some of the things that had were 1.8 stroker kit from Jun ,jun Ecu , jun cams .
an im sure that much more , so if they were able to pass a car with different displacment and also different ecu . im sure that your case shouldnt be a problem .
you should check them out ...

 

Hmmm... yeah because basically... I will drop in some CTR pistons if when I get sent to state ref I can pass with them.. I am going to build my motor with Toda Bs or Jun 3s, and if all I have to do to pass the state ref is remove the cams, and if I can pass with all my stock parts <u>but</u> the pistons, I'll build my bottom end. I just don't wanna drop in some CTR pistons, get sent to state ref and find out I need to take apart my whole block and replace the CTRs with stock pistons in order to pass!

 

if it comes down to that much do to high CR , lots of head gaskets
why do you say went i get send ? you know that you going for sure ???


[Modified by Spoon1, 11:04 AM 6/22/2002]

 

No I'm not going for sure... I only ask because I know how police are down here, and I know that eventually I will be pulled over and sent there, but hopefully that won't be soon *knocking on wood*

 

you will fail the NOx numbers depending on how high you go.....

 

I want ~12:1 compression. Will it pass? If not, is there a way to make it pass without removing the pistons?

 

Use an thick headgasket to lower compression when needed.

 

Would that work Reid? If I needed to go to state referee and had CTR pistons in there which would yield ~12:1, could I just get a thick headgasket which would drop it down, and pass the test?

 

I'm not sure about passing the test (not familiar with smogging and such), but I'm sure you could use that method to lower compression.