Edelbrock Proflo 4

[Kain]

the one on the right in that^^ pic is where i hooked booster to

 

[6872xtc]

it doesn’t appear to.

View attachment 361833

Well that's crappy! Doesn't make sense to me.
The fitting in this picture may not be the one that I kept, don't remember.

 

[skunked]

the one on the right in that^^ pic is where i hooked booster to

With a reducer of some sort? The booster line is larger.

Well that's crappy! Doesn't make sense to me.
The fitting in this picture may not be the one that I kept, don't remember.

View attachment 361868

That’s what I was looking for.

 

[Bent77]

Took mine straight out of the port in the runner

 

[mrk5]

Where are you guys connecting your booster vacuum source? I have two nipples on the back of the throttle body, both are too small unless I run some sort of reducer fitting.

I run mine out the port on the throttle body too. However, I purchased some 11/32 hose because I wanted a tighter fitting hose for the PCV and brake booster anyway so I didn't notice the fit being a problem. I still add the spring clamps too. I also used 5/32 hose instead of 3/16.

I used the threaded port in the runner for transmission and the AC/heater thingy that's mounted on the firewall shaped like a sphere.

 

[skunked]

I run mine out the port on the throttle body too. However, I purchased some 11/32 hose because I wanted a tighter fitting hose for the PCV and brake booster anyway so I didn't notice the fit being a problem. I still add the spring clamps too. I also used 5/32 hose instead of 3/16.

I used the threaded port in the runner for transmission and the AC/heater thingy that's mounted on the firewall shaped like a sphere.

My plan was to try the proper 11/32” hose too. The front ports run to the PCV and FPR.

 

[skunked]

I picked up some 11/32” booster line which fit the port on the back of the pro flo well however it’s a really tight fit at the booster. I had to use my shrink wrap hair dryer to heat the hose so it would stretch over the brake booster check valve. The counter dude at Napa mentioned that some aftermarket boosters call for the larger 3/8” vacuum hose however that’s a pretty small difference compared to the 11/32”.

 

[Bent77]

@mrk5

I see you made it to work

 

[mrk5]

Unfortunately I have to work to pay the bills. Did you honk, I thought I heard a honk at some point. Now every time I hear a horn honk I wonder if you are somewhere near by.

I still have 3 problems going on.

1. The whistle from 25-30% TPS. I covered the IAC port and it's still there. I did a quick check for an intake leak that I read on the PF4 forum; cover the IAC and turn the idle speed screw all the way out to fully close the throttle blades. Allegedly, it will keep running if there's a manifold leak, but mine died as soon as the throttle blades were closed. It occurs in all 3 gears, but in the lower gears it's less noticeable with the RPM's higher. It's just like you would imagine whistling on the edge of a piece of paper; if you blow too hard it won't whistle, you have to find just the right air speed to make the whistle. I'm thinking it's gotta be air flow across the edge of a gasket. I ordered a new base plate gasket and I'm going to trim any excess away from the edges of the openings to see if that makes a difference. Otherwise, it's probably an intake gasket that's hanging a little past the edge of the port. I was thinking I could actually check that with a camera scope one of my co-workers has. I guess the other thing I could try/check is the edge of the throttle blades. I can make sure there isn't some sort of raised edge or something.
2. I'm very happy with the idle operation I have it set up with, but the 1 time I'm still having trouble is putting it in gear after starting it when the engine is cold from setting several hours. If I 2-foot the pedals the first time I put it in gear, it's fine after that. I just have to give 1% or 2% more throttle. I figure this I will work out over time. I probably just need to mess with either cold start enrichment or maybe crank fuel. I haven't had much time starting the engine when it's warm to see how it starts and goes into gear; mostly it's either cold iron starts or starting it after sitting less than an hour.
3. I haven't mentioned this before now, but since doing the PF4 install I have noise in my stereo speakers. It's a steady ticking noise with slight background static. It does change with RPM. I thought maybe it was 2 plug wires I noticed were looking bad. I used the factory spark plug holders, and I think they may be a bit too tight for 8mm wires. You can see them in the pic below.

Anyway, it thought it looked like the insulation on 2 of the wires had been damaged so I replaced those with some wires @1977k5 gave me years ago, but the noise is still there.



So I have some new plug wires coming and I'll swap them all out. I'm thinking the new coil probably puts out more juice than the old one. I'm also wondering if the firewall location could be contributing. I figure new plug wires will at the very least eliminate that possible source.

I'm also thinking that if the stereo is picking up RFI, I would like to get rid of it so it's not affecting the EFI as well. Plus the noise is annoying.
​

On Friday I replaced the plugs. They had about 3 years and 20,000 miles on them. I thought there was some chance they could be a source of my RFI in the stereo and maybe also some of the cold start issue. I also figured it would be a good idea to start with new plugs after making the induction changes. I made sure the new plugs were resistor type. This is what most of the old ones looked like with the exception of #7 & #8.



The worst one is from #8. #7 was similar, but not as bad.

 

[Bent77]

On the whistle
Are you using a open gasket under the throttle body or a divided one

Thought on the RFI
Originally 73 may have had a resistance wire to the coil on the dizzy. Double check the voltage out put on that if you reused that feed to anything on your PF4
Otherwise check where the power is going to and from for both the PF4 and the radio. Sometimes that RFI is only in the spark plug wires if you don’t use a suppression core

 

[mrk5]

The gasket is whatever it came with. The new one I ordered is open.

I know when I melted the ignition switched wire, the voltage on it matched the battery. I thought it seemed low, it was 11.8V so I had checked it against the battery, but the battery was also 11.8V. This was the day after having the ignition switch on for the entire flat tow home so it had drained the battery down some.

When I found the wire on the exhaust I thought it might solve my stereo problem too thinking it was caused by the wire grounding to the manifold. But it didn't. So this is a problem from before and after the shorted wire.

I had also read about the alternator causing feedback issues so I added a ground wire from the really long bottom bracket bolt to the battery. Then I also have a big ground strap (it was one I had laying around) from the back of the passenger head to the firewall. Another ground wire from the block to the battery. There's also a ground wire from the battery to the frame and the typical ground wire to the core support. I have seen where some recommend a ground strap on both heads, but I haven't gotten that industrious.

The radio is powered off the factory wire plus an added wire for battery power from the fuse block. The factory plug only had ignition/accessory power since it didn't have stuff that needed to be powered when the truck was off.

 

[Bent77]

I put a divided gasket on. If you remember back from your Holley Sniper days when we were cool, they said that was the main cause of whistle on the intake

 

[folkenheath]

Was yours a dual plane intake?

 

[mrk5]

I put a divided gasket on. If you remember back from your Holley Sniper days when we were cool, they said that was the main cause of whistle on the intake

I'm still cool. I had to use a 4 hole gasket on the Sniper to stop the noise, but it was happening anytime the throttle blades were opening on that one. The PF4 is only at 25%-30% throttle position.

Was yours a dual plane intake?

I do have a dual plane under the Sniper. It's the Weiand 8122 made specifically for the peanut port 454 heads. I know there's been discussion about single plane intakes for the TBI type EFI, but mine idles and runs great.

 

[folkenheath]

I do have a dual plane under the Sniper. It's the Weiand 8122 made specifically for the peanut port 454 heads. I know there's been discussion about single plane intakes for the TBI type EFI, but mine idles and runs great.

I was referring to the divided gasket which was suggested, I think a divided gasket would be worse with a single plane intake because there is nothing there to sandwich the gasket.

 

[Bent77]

I was referring to the divided gasket which was suggested, I think a divided gasket would be worse with a single plane intake because there is nothing there to sandwich the gasket.

Yeah I forget that whole open plenum thing. Thanks for correcting that!

 

[mrk5]

It baffles me why Edelbrock puts a throttle body gasket in there that has the dual bolt pattern. It's a complete unit, why would I need the other bolt pattern? On other applications I've had trouble with a leak thru the extra hole.

 

[folkenheath]

I agree, I was surprised by that too, sometimes it's hard to find a single pattern 4150 gasket these days but you would think at least one of the two main carb manufacturers could.

 

[mrk5]

2 victories and 1 stalemate today.

Installed new plug wires; MSD Super Conductor 8.5mm wires.



Spendy, but I wanted to be sure. Victory #1, the feedback in the radio is gone.

I also changed out the gasket under the throttle body with this one. Holley 108-10



I trimmed about 1/8" off 1 side and the front of the inside opening so none of the gasket was hanging over the edge.



Unfortunately it didn't eliminate the whistle noise. So that's a stalemate.

I'm just going to let it go for now. If I'm listening to music at my typical volume, I don't even notice the noise. If it really bothers me, I just have to move the throttle a few percent and it goes away.

Victory #2 came at the gas station. With the carb I was getting 11.25 mpg consistently on my typical daily commute. On a few trips with almost exclusively highway driving, it pushed into the 13's. Today I calculated 14.2mpg after my commute driving. That's solid 3mpg improvement! If that holds, I'll save $600/yr with gas at $2 a gallon.

That's a better payback than I expected. I thought I would see mpg improvement, but not enough to pay for the cost of the EFI in less than 5 years. I'm pretty happy about that.

On the whole, I'm getting to a happy place with the PF4. Unfortunately the whole business with the wire shorting on the exhaust causing it to randomly die, has delayed my satisfaction with the PF4. Almost like a traumatic experience, it's taking me a little while to get to the place where I can drive it and not be holding my breath waiting for it to die. The kicker is, that was all my fault.

 

[6872xtc]

@mrk5 I can understand your wariness, but let me tell you that I drove mine for over 8 hours a few months ago. I think that we shut it off twice for less than 10 minutes each. Running all alone, every speed from double low to 80 mph on I-70.
NEVER did it die or do anything goofy.
I was proud of that dang truck that night!


I feel that you will get to the point of trusting it completely very soon.