8.5:1 comp ration on a n/a ka

[sliksta1]

i came across this 97 240sx (ka24de of a s13) that was previously turbo'd and was built with JE pistons 8.5:1 CR and eagle rods and used a SAFC II for tuning i guess (i dont know anything about these SAFC II except that its air/fuel controler and such, never messed with one). the previous owner blew the turbo up or some chit. now the car is running n/a. and so it has a really low stumbly idle. sounds like shit. i do know lower comprssion ratio is for turbo and higher compression ration is for n/a. but my question is would this compression ratio 8.5:1 that it is currently running make the idle really low and stumbly?
thanks for your input. i did search for a answer that would explain my question but couldnt find someone with a simular situation.

[kapeta34]

was is retuned after the turbo was taken off?

[sliksta1]

im not sure really. the previous owner used the SAFC II for the turbo set up and i dont know how to even put it back to stock setting. i dont have a users manual or anything. im going to see if i can find one on the net.

[sliksta1]

i found the instruction manual. im gonna read it and see what i can do.

[PoorMans180SX]

Yeah. That thing is going to be a dog no matter what you tune it with.

8.5:1 for NA sucks.

I would say buy a new turbo system (or whatever you need) and something real to tune it with (SAFC is NOT a proper tuning device when used alone), or get a different KA/rebuild that one with higher compression pistons.

Seriously. That's the only way that car will ever run decent again.

[sliksta1]

thanks for the input i have a extra t25, intercooler, sr injectors and i BOV lying around. but i like the gas milage it has compared to my sr13 w/2871, 740's, and N60 MAF. setup so im still undecided if i want to go turbo. i probally wont and end up selling the SAFC II and extra stuff.
my computer isnt equiped with the japanesse language converter thingamajigg. so icant look at the manual off apexi site. i'll try to find it else where if possible.

[KA-T_240]

I would start with checking these things:

What injectors are in the car right now? If not stock put the stock KA injectors in
If they are stock 240sx injectors, set the AFC to all 0.

If you do the things above and it doesn't help check the timing.


That C/R will be decent for a NA car. mine was 9.0:1 and it was just as fast as a stock 240.

[sliksta1]

im thinking of just taking the SAFC out of the car and seeing how that does.