Since installing TES headers and Flowmaster catback exhaust with Dynomax high flow cat, my 92 Camaro runs sluggish at cruising speed. My spark plugs are rapidfires gapped at 045 not 035(stock setting). Should I advance the timing or regap the plugs to 035. I have plans in the future to install my MSD 6AL....

 

Try advancing your base timing. It cant hurt anything and if its wrong just back it down.
I would try it a 8* then 10* and then 12*
8* should be good for your application but more is better .
SSC

[This message has been edited by SSC (edited October 06, 2001).]

 

Thanks for the tip....I'll give it a try.

 

You should reset your gap back to .035" if you have no present ignition mods. The reason the General uses such a small gap is to allow the spark to jump while using the cheaper coil and module that they put in stock engines. If you increase the gap, then you are causing the spark to jump (arc) an increased distance. This also increases the resistance that the elec. current sees and will reduce the strength of the spark. This can cause a reduction in efficiency which will lower output and increase fuel consumption.

On the contrary, if you increase the strength of the spark by use of a better (stronger) coil and module, then you can increase the gap and gain efficiency and "Re-gain" any lost output due to the poor stock coil.

Let it be know that a better ignition system does not, per say, "make" HP. It only unleashes HP lost through poor efficiency.

The timing varies on the engine size, the way it's set up (comp. ratio, cam size, etc.), atmoshperic pressure, the temp. of the intake air, A/F ratio, and many other things that are too difficult to explain here.

The best answer I received when I asked that question was to get a hold of a diagnostic scan tool and check the knock counts. Set your timing on the ignition based on the knock sensor detecting very few, or no knocks.

I have to admit that I tried 4 deg BTDC and thought I felt a little more "Umph" using the SOTPM. After a while I set it back to 0 deg BTDC and noticed no loss in "Umph". I'm sure that I felt and increase because I WANTED to feel one.

I guess I'll wait and get a scan tool. The only other reason I might fiddle with it is at the drag strip to try and shave a few tenths off my ET.

Hope this helps a little more,
AJ

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92 RS w/t-tops 305 TBI Auto.
170K miles and don't burn a drop o'oil
-K&N Truck filter #1500 w, open ele.
air cleaner
-Dynomax 2 1/2" cat-back
-B&M TransPak
-Jet Stage2 Chip
-180* T-Stat w/ 185* Fan Switch
-JVC CD--Alpine speakers & 4ch. amp
Rockford Punch 100. 1 - MTX 12" sub

[This message has been edited by AJ_92RS (edited October 06, 2001).]

 

Hey AJ & NOC, Do your cars all say 0.35 for spark plug gap?
Wierd thing is Ive always set them to 35 as a standard but last time I bought plugs the chick working at the store spouted off "they need to be set to 45 gap!" Astonished and thinking "what the H$LL does she know" I checked my sticker and low and behold it said 0.45
SSC

 

Some cars say .035, some say .045. ANY STOCK HEI IGNITION CAN RUN A .045 GAP. Be it the early coil-in-cap design or later designs wih the small distributor and separate coil, .045 is just fine and dandy for any n/a motor.

The overall HEI architecture is basically the same from 1974 through 1997. Only the timing mechanisms changed dramatically, the electronics are largely the same.