Before anything I already did a search it turned up 18 pages and I only went through the first couple...anyways I have a 90Iroc lb9/auto etc. I have already done the tb bypass and cut the baffles out beneath the air filters. I have completed a full tune up except fuel filter which is sitting in the garage and will be replaced tomorrow...done cap/rotor/plugs/wires/coil etc... Are there any more free mods that I can do?

 

under hood insulation

 

Advance timing to about 8-9 degrees @ idle with ESC wire diconnected.
Assuming you are not getting knok retard - best if done with a 160 thermostat to cool cylinders more.
That will probably net biggest gain.

 

you think with a 160 stat and premium that I could bump it up a couple more degrees than that? like 10-11? Right now it is sitting at 6*

 

Possibly but, If you get knock retard you will lose more than you gained .
Get a scanner or voltmeter and watch knock retard.
Or just watch track times.

 

How can you tell when there is knock retard?

 

Well there are a few ways, Easiest way is with a scanner or laptop. If you have access to a laptop, Craig Moates makes awsome scanware that is free! all you have to do is build or buy a cable.
If no laptop- buy a scanner, these tools are pricless when modding a EFI car in my opinion. And they will also teach you alot.
Either of those will tell you, But like I said watch track times as well.
Fisrt try 8-9 degrees then maybe 10-11. My car ran best @ 10 degrees when stock.

 

If you dont mind gettin your hands dirty you can yank off your plenum and ground off the egr blocks that are near the throttle body, also while your in there you can clean and polish the bores on the throttle body too. Since you did a full tune up, i assume you checked your IAC and TPS sensors.

 

Changing the stock timing on TPI usually doesn't do a darn bit of difference, except slow you down more due tot he knock sensor. I recommend just leaving it at 6 degrees.



Your better off fully porting the plenum, and shedding pounds.

 

how do you check knock retard with a voltometer??

 

I got times before and after to prove it helped me alot.
Like I said watch knock retard and track times.

It also depends what prom your car came with , for instance the arap came with much more aggresive timing table because the alum heads on vettes. But there are several different for 3rd gens.
People generally try to add to much, or do so with 87 octane or higher coolant temps causing excessive knock retard.
Try 8 then maybe 10.. Watch times as I said.

 

To test for knock, you would need to splice into the knock sensor wire. It gives off an electrical signal if it detects detonation. Just hook up a voltmeter in line with the wire.

 

But easiest method would be to get yourself a scanner..
You will love it.

 

it would be way easier, but not cheaper. I got lucky and got a laptop for free. If you have a lap top already, all you need is to load the software and make a cable.

 

got any clue how to make the cable? or a info site thats got good info for a NooB. I got the software and laptop though..thx

 

I've already got an AKM cable and tunerCAT for my 95, it's OBD1 but has the II connector...Is there another cable half I can plug in? I'll check the site...

 

Remove your a/c and air equipment.
I noticed almost 65 more miles per tank of gas after i removed these, so i would assume it freed up a little hp.

 

You should go into the DIY board. I know thats a big step and that board is a little scary but its in there, or you can get one off ebay like I did. 45 bucks and I got a TON of software with it on a CD.

 

Look in the tech articles section, theres lots of nice concise info there.
https://www.thirdgen.org/newdesign/tech/