What's new
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

Edelbrock Proflo 4

6872xtc said:
Have any of you guys adjusted the cold enrichment in the temperature range steps? Or just the global adjustment?
I went into the advanced setting for it, then also made sure that the global didn't change unless I wanted it to.
I had mine change the global when it had the old software once.
I honestly don't think that the AFR when warming up is a great concern, just how does it run. But that's my opinion.
I haven't tried any adjustments for a long time, but mine seems to be good after warming up some.
Click to expand...
I did mess with the cold enrichment using the advanced tab and temperature ranges, but it was making it harder to start and didn't really improve the dying when shifting into gear; made it more of a hit and miss thing instead of always dying. I tried small increments and very large increments without much change. That's what made me decide it was probably my base settings that needed changed.

The AFR warming up only concerned me because the actual wasn't matching the target. It's kinda hard to explain. Let's say my idle target is 13.3; the PF4 was telling me the target was still 13.3, but actual AFR would be much lower and incrementally get closer to 13.3 and finally hit 13.3 when the engine was 165°. It concerned me because the Sniper also runs a richer AFR cold, but it changes the target to show what it's actually trying to achieve. I had thought maybe something was wrong with the fuel map or something. I had to ask on the Edelbrock forum to see if that was normal.
 
mrk5 said:
I did mess with the cold enrichment using the advanced tab and temperature ranges, but it was making it harder to start and didn't really improve the dying when shifting into gear; made it more of a hit and miss thing instead of always dying. I tried small increments and very large increments without much change. That's what made me decide it was probably my base settings that needed changed.

The AFR warming up only concerned me because the actual wasn't matching the target. It's kinda hard to explain. Let's say my idle target is 13.3; the PF4 was telling me the target was still 13.3, but actual AFR would be much lower and incrementally get closer to 13.3 and finally hit 13.3 when the engine was 165°. It concerned me because the Sniper also runs a richer AFR cold, but it changes the target to show what it's actually trying to achieve. I had thought maybe something was wrong with the fuel map or something. I had to ask on the Edelbrock forum to see if that was normal.
Click to expand...
Good to know. What kind of numbers did you go as far as small and large adjustments? 2%? 10%?
I assume that they show the AFR set point for when it's over 165*, is that what they told you? Just curious to know.
 
6872xtc said:
Good to know. What kind of numbers did you go as far as small and large adjustments? 2%? 10%?
I assume that they show the AFR set point for when it's over 165*, is that what they told you? Just curious to know.
Click to expand...
Yes the target AFR displayed is always the 165° setting. The first time I really noticed it, I thought sure there was something messed up with the ECU and/or fuel map. This was after finding the melted wire so then I was sure I had messed up the ECU.

In the past I have tried to do 2 to 4 percent adjustments to cold start enrichment, but when that didn't seem to help I tried big changes like 5 to 10 percent. With the current settings that seem to have cured the dying when shifting into gear, it's still having some trouble starting so I'm trying to be patient and use small 2 to 3 percent changes. It's hard because I really only get 1 truly cold start first thing in the morning. The engine has sat for nearly 14 hours overnight so it's good and cold; that's when it struggles the most. When I leave work and the engine has sat for 9 to 10 hours and warmer outside temperature, it starts easier. It's also so hard to tell if it wants more fuel or less since you don't get any AFR or SFT until the O2 sensor is fully warmed up.

Now that I can shift into gear without the engine dying, I do notice the AFR will spike lean with the added load on the engine. So that supports the idea that the engine needs to be a little richer to keep running after the gear shift.
 
JoshHefnerX said:
I had a conversation w/ a GM engineer one time many years ago. His recommendation was to get the car started, give it long enough to get the oil pressure up and flowing. And then go. Keep the throttle easy, but letting a vehicle warm up in the driveway was harder on them than driving them easy while cold. The fuel enrichment just helps wash the cylinders down, so getting it up to temp as quickly as possible was good - and driving easy would do it faster than idling.
Click to expand...
I do that all time, learned it 30 years ago. That's on stock drivetrain.
But I suspect with this setup it might not work well until it's perfectly tuned
 
Okay pro flo brethren if thats how you spell it. Got a question for ya but before I ask let me give you the specs

454 mark IV .30 over
Peanut port heads (yeah yeah I know)
Headers mid length
No cats
Msd blaster 2
Pretty decent plugs gapped to .45
Wires are like 8.5mm or something (not that oem crap)

Does anybody have a clue what my settings should be for vacuum advance? Its at like 9 degrees right now.
Also what should be advance start RPM be? Its at 1200

Thank you for any guidance
 
That seems decent to me for the vacuum advance. Does it like it? You would have to try other settings to see how it responds.
I like to have the advance start at 900 to 1000 rpm. All in by 3000.
 
Unfortunately Edelbrock software sets the vacuum advance at 28 inHg, which your engine will never see, so you are only getting a fraction of that. I would max it out since it only goes up to 15 and you will probably only see ~10 of that if your engine has ~20 inHg, which many don't even have.

I would like to see them offer a two number setting, a max number not to exceed in degrees, and a degree/inHg, so you could set that anywhere from 0 - 3 degrees/inHg, that would work much better.

I hope they change the software and someday this post is wrong and out of date.

I have my WOT timing at 36 and my vacuum can at 16 degrees, but that's not even possible with the Edelbrock software.

And I agree, start your RPM timing ramp up just about idle, maybe 900 - 1200, and ramp it up to full timing by 2 - 3k. Maybe higher RPM(slower ramp) if you have a low RPM towing motor or if you get any pinging down low for any reason.
 
I'll give that a go, yeah I think it likes it, think blows these 35s off like nothing lately but I just don't know much about tuning
 
nmxhustla said:
I'll give that a go, yeah I think it likes it, think blows these 35s off like nothing lately but I just don't know much about tuning
Click to expand...
folkenheath said:
Unfortunately Edelbrock software sets the vacuum advance at 28 inHg, which your engine will never see, so you are only getting a fraction of that. I would max it out since it only goes up to 15 and you will probably only see ~10 of that if your engine has ~20 inHg, which many don't even have.

I would like to see them offer a two number setting, a max number not to exceed in degrees, and a degree/inHg, so you could set that anywhere from 0 - 3 degrees/inHg, that would work much better.

I hope they change the software and someday this post is wrong and out of date.

I have my WOT timing at 36 and my vacuum can at 16 degrees, but that's not even possible with the Edelbrock software.

And I agree, start your RPM timing ramp up just about idle, maybe 900 - 1200, and ramp it up to full timing by 2 - 3k. Maybe higher RPM(slower ramp) if you have a low RPM towing motor or if you get any pinging down low for any reason.
Click to expand...
Thank you! My engine is usually around 18-20 vacuum at idle and thats all I knew about vacuum so when I seen vacuum advance I was like what the hell is this
 
The vacuum advance on the PF4 works like ported vacuum on a carb. So it doesn't add anything at idle.
 
mrk5 said:
The vacuum advance on the PF4 works like ported vacuum on a carb. So it doesn't add anything at idle.
Click to expand...

Thanks for adding that, you are correct and I forgot to mention it.

I wish that was selectable, or not the case, most engines respond better to having more advance at idle with low load.(the reason it was not used at idle sometimes was mainly emissions) But the way they have it programmed if you had a decent cam and the idle vacuum was fluctuating it would fluctuate the timing too because you can't set a limit or a rate, so its going to keep varying the timing all the way to 28 inHg, which it will not achieve.
 
I am installing my kit currently. I went ahead and installed a 195 thermostat. The instructions say use a 180.

I do have both and did use a nice new water neck with reusable gasket so I can switch it back easily before filling which probably won't be this weekend sadly. I'm still waiting on the arrival of my fuel system fittings

What say the CK5 PF4 masters, use the 195 or the 180?
 
From a factory standpoint, more heat helps to run lean and help emissions. Obviously @nmxhustla hasnt felt the need to switch
 
IMO...
Big block... 180
Small block w/ low compression, AND if you need a good amount of heat for the winter... 195.
High compression engines with todays fuels will be better off with 180

My vote is 180. Heat is still plenty for me here in Colorado.

Good article here
https://www.hotrod.com/articles/how-to-choose-a-thermostat-for-your-classic-car/
quote-
Will A Colder Thermostat Increase Power?
It is our experience, and the experience of other trusted sources, that a colder thermostat temperature will tend to increase horsepower and torque slightly. A great example of this can be seen in episode 43 of Engine Masters on the MotorTrend, where they run a 598 c.i. big-block Chevy on an engine dyno at Westech Performance Group in Mira Loma, California. First, the engine was run with coolant temperature at 135 degrees, then at 200 degrees, where it lost about 18 horsepower and 15 lb-ft of torque at the higher temperature. That might seem like a big loss, but the big-block Chevy was making 854 horsepower and 790 lb-ft so if you do the math, that's about a 2 percent decrease in power and torque.
 
Shawn said:
IMO...
Big block... 180
Small block w/ low compression, AND if you need a good amount of heat for the winter... 195.
High compression engines with todays fuels will be better off with 180

My vote is 180. Heat is still plenty for me here in Colorado.

Good article here
https://www.hotrod.com/articles/how-to-choose-a-thermostat-for-your-classic-car/
quote-
Will A Colder Thermostat Increase Power?
It is our experience, and the experience of other trusted sources, that a colder thermostat temperature will tend to increase horsepower and torque slightly. A great example of this can be seen in episode 43 of Engine Masters on the MotorTrend, where they run a 598 c.i. big-block Chevy on an engine dyno at Westech Performance Group in Mira Loma, California. First, the engine was run with coolant temperature at 135 degrees, then at 200 degrees, where it lost about 18 horsepower and 15 lb-ft of torque at the higher temperature. That might seem like a big loss, but the big-block Chevy was making 854 horsepower and 790 lb-ft so if you do the math, that's about a 2 percent decrease in power and torque.
Click to expand...
Well if changing from 135 degrees to 200 got a loss of 2%, I wouldn't bother with the gains from going 180 from 195, it most likely be less than 1% gains.
If I get a cleaner burn which also usually means better mileage I would take that
 
You must log in or register to reply here.

Latest Posts

Top Bottom