well i'm assuming my 390 has upwards of 10:1 b/c on a strict 93oct diet and 12deg timing its pinging...not bad but it does if I get on it good! I wanna be able to crank up the timing on my 390 and also utilize my secondaries b/c if i do nothing with the way it is then its just gonna get worse the more my foot gets in it. Why not turn down the timing? B/c I would be going backwards as to the reason I built this motor. I want power and mileage just like anyone else but I'm willing to experiment. If i turn down the timing, it would stop the pinging which is where I have it now at around 10 degrees but theres a power loss and efficiency loss. Another 220 bucks and I'll have even higher compression, better miles, and no pinging. I couldn't understand not getting this kit. Thanks Ron for the recipe. I def want that meth!

 

It will not raise your compression. Only let you run what you have with more timing and less pinging.

 

Did you look at your spark plugs? Maybe a cooler heat range is all you need.

 

Well right off the bat when i built the motor I installed 124 autolites. I'm not sure how many points cooler that is from stock but thats what my FE specialty bud told me to start out with. In 2500 miles I've put a new set of 124's b/c I burnt so much oil at the beginning from not having the performance oil drainbacks on the rockers which I now have. She likes to ping with any more than 10 degrees but this could also be as simple as getting the correct centri adv weights. I could be deceived but for 220 bucks I will wipe out any pinging, get more miles, up my octane to where I can run on 87. I think this thing would pay for itself in a years time. Am I overlooking the obvious? I will eventually determine what centri weights I need but I don't have the time to figure that right now. I'm hopin to stumble across some old man that used to build dizzy's.

 

Also ron, after reading your post...duh it won't raise your compression! After I thought about it, when your secondaries kick in or even when you just put your foot in it, that doesns't make your compression go up just simply b/c your putting more fuel in. Same goes for water vapor...just something else going in and going out. Compression is made mechanically. Thanks for setting of the light bulb Ron R.

 

The problem I see is that system, as far as I can tell, wasn't really designed for part throttle cruise. It is more of a WOT ping eliminator. I dont think it'll help going down the road, unless you set it up that way. And if you do, think of all the money you'll spend on windshield washer fluid! I think you'll be money ahead to just change the timing and get a hair worse mileage.

Now maybe running the water injection at full throttle only would be enough. Maybe it would be enough to keep the chambers clean enough that you dont have to change the timing at cruise. But dont count on it. Plus, you'd have to go to WOT regularly enough to keep 'em clean, or the pinging would come back.

According to the spark plug number you've given, that would translate to Champion number RF10YC. I've been running cooler plugs in mine, RF9YC. You might consider doing the same.

So, are you having problems with pinging at cruise (going down the highway) or not?

 

With an empty bed and 93 octane, it pings if I hammer it off idle and climbing hills. I don't notice it so much when I'm on the interstate and that could be either b/c my trucks is too loud to hear with my flowmasters or it doesn't ping. Just cruizing it does fine but when I call for more power and put my foot in it, thats when it starts to ping a bit. It all depends on how much ww fluid i'll be using. If i can put a gallon container under the hood and burn a gallon every oil change/3,000 miles...that'd be fine. Not so sure I can get away with that though. That is a prob though Kurt, the system I would get is designed to be either fully on or fully off. No partial injection. Now I think but am unsure if I can get a vacuum adjuster so that it comes on so much with so much vacuum. Whatcha think?

 

Well that would make a little more sense then. I do believe I read somewhere that you can hook it up to turn on after a certain throttle opening. That's probably what I'd do.

Or just get stiffer advance springs. It sounds like the vacuum advance isn't giving you any problems.

But yeah, now it's looking a whole lot better for this kit! Let us know how it works.

 

Well the whole time I've been runnin the motor since I built the 390, I've had the vac adv disconnected b/c I was already havin probs pinging. I don't know what it would run like with it connected. I know you can't answer this for sure over the net but would you just start with stiffer centr adv springs and go from there? How many choices of springs do you have? The way I see it...which isn't always the best, if I can tune my 390 to perfection and get 15-16 mpg and then install the Snow, and with my gearing, I don't think 20 is too far off! Now I may be dreaming but hey I'd like to pursue it. Then I can tell everyone I have a 350+/- hp v8 that gets 20 mpg!! Am I dreaming while I'm posting???

 

J ust my own 2 cents.....Like mentioned above, I think I would dail in the timing the best you can with a kit...and see where you are there...and then worry about the Water injection...

Because if Shoot forgot his name...Damn..well anyway ..can run 11 to 1 cr with 93 octane with Iron heads..12 sec. truck...you should be able to dail in your timing as not to ping..and then go for the injection to rust out the exhaust!! LOL.. JK..

RJ

 

A couple things I'd spend money to find out...
So you changed the plugs...Do anything to clean the combustion chambers? A "steam-clean" might actually have some benefit here.

So this is the old, tired dizzy? I would think the advance springs are due. With all the discussion of initial advance, I have yet to see what your total advance is, or at what RPM it's all in.

I'm counting the other guys to correct me on this, but, IIRC Bear 45/70 says 34* or maybe 36* max for mechanical advance. It's a big enough deal that he says to set timing by your total and let the initial fall where it may.

For some reason, having all the advance in by 2700 RPM falls outa my head. Don't take that as gospel, that's just what falls out when I shake real hard. Maybe someone else can help with that info.

For $220 you can have a new tach/dwell meter, an adjustable timing light, an assortment of distributor springs, and a few tanks of gas. I'm not saying to not experiment, I'm saying I'd start with clean combustion chambers and complete knowledge of the advance curve. Let the mad science begin!

Russ, aren't you thinking of polecat? Doesn't he run a cam with a bit of overlap? Somehow I don't think he's getting 12 to 15 MPG! LOL But he sure do RUN!!!

 

Ya Polecats got the 428 using the same head gaskets as I (Vic Reinz) and he's runnin 87 oct if I recall correctly. I just need to read up on how to set my dizzy curve to my engine and drivetrain. puttin a taller gear in also makes for some more math. Is there like a dizzy kit that comes with an assortment of springs and weights that I can get? I'm def more for doing that if it cures the pinging. The last thing I want is something else to have to maintain like the snow. Hey Kurt, what weights are you running in your dizzy on your 390? I'll see what weights I have and post them if ya'll think that would get me going in some direction.

 

Right now I have fairly light ones in there. But that's only because I'm now running E85. I'd have to go tear apart the distributor to look, and I'm not doing that right now. I do remember that the ones in there would NOT work with gas; it rattled at lower RPM's at WOT. The ones that fixed it were fairly heavy. That's one of the reasons I went to E85, so I could run a better timing curve.

So yeah, back off your timing, get it right without the water / methanol kit, THEN you can start adding your timing back!

Although, I do hear there's a new ethanol plant going up in Georgia, so you might have access to E85 sometime in the future.

I'll see tomorrow if I can dig up the springs I was running on gas.

 

Here's a question. What if I went to the local yard and snagged a dizzy out of a 390 in a truck and installed those weights and springs into my dizzy? This whole recurve thing is making my head hurt after reading up on it and it kinda is leaving me at a standstill. I can get the recurve kits through summit or jegs but how do I know which kit to get? I'm gonna see what my total advance is today and I'll post that later but I have no idea what to do. If all there was to it was just springs then I could play with springs but I've got weights too and am not sure whehter or not change just the weights, just the springs or both??? Now I remember why i left my dizzy the way it is when I built the motor!! Not enough old men around who've done it!

 

If you were going to grab the distributor out of anything, it should be out of an earlier 4 barrel 390, in a car. That would more closely match your motor.

I never changed weights in mine, just springs. I looked and was unable to find a recurve kit! I know Crane used to make one, PN CRN-99606-1. But I couldn't find it; I suspect it's been discontinued.

Maybe some of the old men on here have an idea?

Edit: I found it! Summit number CRN-99607-1. The article I was reading had the number wrong. Anyway, that looks like the one. Here's the instructions:
http://static.summitracing.com/globa...s/crn-271e.pdf
Now they show a Duraspark distributor, but the kit should work fine on an older points distributor too.

Anyway, there ya go. Instructions and everything. And we can walk you through it too, as I think in their instructions they specify way too much total advance.