So, I've heard several different opinions on how far to retard the timing and at what shot. According to the Zex "Tune-Up Sheet" there is no retard needed for their 75 shot, 2* for 100, and 4* for 125. I'm planning on going with 125 (I assume it's crank hp since there is only a 4* retard and it is after all Zex) and intended on buying the 6AL with the timing controller. After doing more research however, I've come across the mallory products as well as several claims of LT1's on 150 shots without pulling timing.

So my questions are:
How many of you are actually spraying shots that high without pulling any timing and without any knock? (I have no way of monitoring knock retard, fyi)

Besides the price, what are the differences between MSD and Mallory? I found the Mallory site pretty uninformative. I liked the idea of having the controller in the car like the MSD (dial on timing controller) but if it saves that much money for no disadvantages I'd go with the Mallory. I already have a window switch.

And lastly, those of you that have done testing with ways of monitoring everything, what have you found to be the least amount of timing pulled safely while spraying certain shots?

My car is basically stock, power wise(catback, ram air), and won't exceed having long tubes and ORY for a while.

 

If the car has stock timing you can spray a 150 shot with no problems just run a colder plug like the TR6's. I have sprayed several passes on stock timing at the 150 level. I sprated a 150 with a couple extra degrees of timing after I put the cam in.

Then I went with the mallery 685. One box pulls timing and window switch made it easy.

If your running a 125 then you don't really need to pull any timing.

 

Well, sorry if this is an ignorant question (I'm just getting into EFI tuning), but how do you know the knock retard isn't pulling timing? Would this not even occur with a wet shot since the MAF reading is irrelevant?

 

JakesZ28? Anyone?

 

I also have a question if you run a tune from say madz28 were they advance timing when you add a box does that set the timing where you put it or do you have to take extra timing out when you run Nitrous.

 

you can run 100-150hp on "STOCK" timing....if you have tune where the timing was advanced you will at least want to retard the timing back to the stock setting when the kit is activated. There are many different options to do this with the LT1

The Mallory 685 is a good, all in one, box as it puts the ignition box, timing retard, spark rev limiter, and window switch into one unit.

Crane, MSD, etc all have timing retard modules that can be added to an existing ignition box, if you already have one.

FOr any nitrous use you will want to run at least a one step colder plug

 

man, this what you do,...
get a retard box, and have it hooked to the nitrious selonoid
(only being activated ONLY when the nitrous is activated)
use a 4 degree pill, w/ 200wetshot ... just to add, do not keep ur perfomace CHIP in because
it is (advancing). and if ur SURE ur not going to spraying for a while,
then put the CHIP back in...cool. i've been around in this game, and to
me a retart box is a retard box...whatever the name is... just (retart) only at wide open throttle, it's the best time for the motor to see any dope.

 

Chances are the pcm is pulling some timing running N/A. They tend to pull timing easily. The factory thought safety over power. I LT4 knock module will help it out.

On my car some days it doesn't get any spark knock other days it is there while cruising. I currently changed the tune so at WOT the timing can not be pulled.

Wet or dry will make no difference on the timing. The LT1's don't like a dry kit thru the MAF. The PCM can only support abot a 50-75 shot thru the MAF but that has to be verified with a wideband. So go with a wet kit or a dry one that spikes fuel pressure. Hopefully that helps.


Back on the knock retard the only way to see it is with a datalogger. Something like TTS datamaster or scanmaster.

Let me know if you have any other questions.

 

Thank you. I always wondered that I guess if I get a tune and decide to run spray I need to make sure to know how much they advance the timing.That way I can pull it out with a box if I decide to spray.