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I have the old Pro Flow system on a ZZ502. I got her started for the first time last week. I believe I messed up and didn't have the small tooth centered properly in the hall effect sensor. That and some orientation problems with the fuel gauge wouldn't let me get enought timing, so I only ran the motor a short time.

After moving the gauge, I started all over yesterday and put the distributor in right (I think).Setup is to put the small tooth inside the hall effect sensor with the motor set at 10 degrees BTC. I started it up and had like 30 degrees BTC at idle. I thought this wasn't right but the motor ran fine and I went ahead and ran the motor about 20 minutes at 2-2500 RPM to break in the cam. Then the top hose blew off the radiator with me bent over the motor running the throttle. Could've really cooked me but I got lucky. Dad got there, I put the hose back on, and we started messing with the timing. He's an old time that doesn't like computers but he too thought the advance was way high. There is a part in the book about setting the base timing. Basically you turn off the computer advance. I did this and the motor ran crappy of course and started to get hot. You are supposed to use a timing light and turn the distributor to get 10 degrees BTC at 1500 RPM. We did this and it set fine. Went in and turned the advance back on and it did the same thing, around 30 degrees-sometimes closer to 40 degrees of timing. The timing light matched almost exactly what the calibrator in the Edelbrock kit was saying so I know it was a correct reading. I couldn't figure it out. I ran the motor a few minutes and changed the oil.

Today I called Edelbrock and talked to what sounded like a very knowledgeable guy. He said from what I told him it is running exactly as it should. He said while idling with no-load, that he normally sees about 30 degrees of advance. He said this makes the motor run more efficient. He said as load increases, the timing may retard some even if RPM's go up. Just depends on the load. I guess it gets this from engine vacuum and the MAP sensor? He said I need to set my Idle and it should be ok.

Has anyone had any experience with this stuff? Is this what you've seen. He said he's been asked about this many times. My only question is why isn't this in bold print in the manual if everyone thinks its a problem when it isn't, as it cost me alot of time and sleep. Breaking in a new expensive motor is scary enough, but not understanding stuff like this is 10 fold.

PS. How does your timing advance that much in a cap? Mine is a big cap HEI and that is one thing, but what about small distributors. At 30-40 degrees, it seems like the fire is jumping a long way to the terminals and seems like it may go to the wrong one.
 

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I have the pro-flo on a 350, same deal. I didnt have a problem with it though. And dont forget if you dont like the timing that high at idle just go into the spark map and adjust it. You can control all the spark and fuel curves right from the hand held interface. On mine I have had to lean it out a lil at idle, was pretty rich. I got a wideband air/fuel ratio meter from innovate cause I wasnt trusting my O2 sensor reading from the pro-flo. I have yet to install it, working on other stuff, engine sits still these days. JR

http://www.innovatemotorsports.com/products/lm1.php
 

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Discussion Starter #3
I have one of these.
http://www.nordskogperformance.net/product.php?productid=18881&cat=102&page=1
It's not a wideband like yours, but it may work some. When I looked at it, it was showing rich, but I was so concerned over the timing and stuff that I really never got to slow down and study the stuff.

So when you say same deal, do you mean yours advances the timing like that also? Later on I may take some time and really try to figure this tuning out. Would be nice to have someone show me or to at least have a good video come with the stuff. I'm surprise they don't. Would also be nice to use a laptop like the newer version, but I don't think it's set up for that.
 

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Yeah, it was advancing the timing also. Thats what I meant. :) I was a lil confusing. Sorry. But, yeah, mine was the same..

I suggest you re-read the tuning "booklet" and play with it. What I did was take a clipboard and paper with me in the car. I started documenting what changes I made cause I wanted to see them at a glance. Yeah, a laptop system has many advantages. But with some parer to show you what changes you made you can go right to the parameter you think is causing problems..

Last piece of advice. Baby steps!! Yeah, too much change is just that, too much. You can change the spark or fuel settings too much and be walking backwards. Just take it a step at a time, small changes at the computer really do affect the performance alot. And document those changes on paper so you can retrace your steps. For me its all fun cause I like to play with the various setting to see where it helps or harms. JR


So when you say same deal, do you mean yours advances the timing like that also? Later on I may take some time and really try to figure this tuning out. Would be nice to have someone show me or to at least have a good video come with the stuff. I'm surprise they don't. Would also be nice to use a laptop like the newer version, but I don't think it's set up for that.
 
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