Hey everyone..

I just plopped a supercharger on my car and am in the middle of tuning it. I am using an '870 ECM and am going to tune for water injection also. What I am wondering is, do you guys modify the timing table itself and how to intruduce PE after lets say 3000rpms.. I tuned my car NA before with a modified timing table really well, but am new to supercharging..

Currently the water injection is not in yet, and my timing table looks like this :

20.0 20.0 20.0 20.0 20.0 20.0 20.0 20.0 20.0 20.0 20.0 20.0
25.0 25.0 25.0 25.0 25.0 25.0 25.0 25.0 25.0 25.0 25.0 25.0
26.0 26.0 26.0 26.0 26.0 26.0 26.0 26.0 21.1 21.1 21.1 21.1
27.1 27.1 27.1 27.1 27.1 25.7 22.9 22.9 22.9 21.1 21.1 21.1
28.1 28.1 28.1 28.1 28.1 25.7 22.9 22.9 22.9 21.1 21.1 20.7
29.2 29.2 29.2 29.2 29.2 27.1 24.3 24.3 24.3 21.1 20.7 20.7
29.9 29.9 29.5 28.5 27.8 27.1 26.0 25.0 21.8 20.7 20.4 20.4
31.3 31.3 30.9 29.9 29.2 28.5 26.7 26.0 22.5 20.7 20.4 20.4
32.3 32.3 32.0 30.6 29.9 28.8 27.4 26.7 23.9 20.7 20.7 20.7
33.4 33.4 33.0 30.9 29.9 29.9 28.5 27.1 25.0 21.4 21.4 21.4
34.8 34.8 34.1 32.0 30.9 29.9 29.2 28.1 26.4 22.5 22.5 22.5
36.2 36.2 34.8 34.5 32.0 31.3 29.2 28.1 27.1 23.9 23.9 23.9
39.4 39.4 38.0 36.9 32.0 31.3 29.2 28.1 27.1 23.9 23.9 23.9
39.4 39.4 39.4 39.4 34.1 32.0 29.5 28.1 27.1 23.9 23.9 23.9
39.4 39.4 39.4 39.4 38.0 35.2 31.3 29.5 27.1 23.9 23.9 23.9
39.4 39.4 39.4 39.4 38.0 35.2 33.0 31.3 27.1 24.6 24.6 24.6
39.4 39.4 39.4 39.4 38.0 35.2 32.3 31.3 27.1 26.4 26.4 26.4



I get ping past 5PSI (I get about 9PSI at 5500 rpms.) right now..

 

Leave the water off, and just tune until you have a really good base calibration, ie no knock, and several degrees of room befor hittting any.

I'm not a big fan of straight water.
A alky based Windshield washer solvent or denatured alky are easy to get, and give good results, IMO.

Start with adding just a *touch* of whatever fluid you're using, and then a little more timing, all the while looking for any knock.

In the end, I'm running about the same amount of boost, but making more power. I have alot of intercooler, and the alky Inj is just a MAT enhancer rather then a necessity. The more effect you want to have on the MAT means running something other then water.

 

Not to hijack the thread, but Grumpy, when you say leave a few degrees room before knock, are you talking like 2-3 degrees, or more?

I've got my VE tables almost perfect, and I've been trying to figure out how I should go about my spark tables on my little project - I'm thinking I'll slowly advance timing until I see it start to retard based on knock, then I'll pull it back until it stops knocking, and then knock off 2.4º from that point, as a 'safety measure'.

 

So your saying that the water evaporization in the combustion chamber isnt absorbing the extra combustion heat and that your using it only to lower MAT ??

lets get this striaght right here. The water/alky etc goes to the combustion chamber in droplet form. during the cumbustion process the Extra heat vaporaizes the water/alky etc. When this happens the transform function of heating abosorbs energy that might otherwise be extra thermal load that lower octane fuels can't handle. Thergo you aviod Detonation and pre-ignition.

while i would say there is some wisdom in retarding the timming first then adding the water injection the real truth is you'll most likely end up in the same place your in after you add the water injection.My biggest fear would be running out of MAF with boost and the fueling problem that will follow.

 

having played with the v6 quite a bit ill tell you that the knock threshold is very edgy with boost. it might only be 1 degree in good weather.

 

Try rereading what I wrote, and working on your command of the english language. Then if you want to ask a question, just ask one, instead of the mumbo jumbo you posted in the above.

No I'm not *using it to only lower MAT*, gads you really are a mental case aren't you?. Only someone with mental issues would even imply that.

Thanks for again, bringing that special brand of nonsense that you have to another thread.

 

Trimmed and closed.

RBob.