Hi from Germany

Grumpy · Apr 26, 2018

while the delay and price issue is rather dependent to location,
the fact the parts tend to be expensive and most of us are broke ,
or nearly so most of the time is all too familiar.

55C150 · Apr 30, 2018

So I tested something while waiting for the 50cc pump. I changed the primary main jet one size smaller and got back to the 4.5 power valve. The jet change was good for the rpm range from idle to around 2.500 rpm. It was a bit leaner. But when I tried to accelerate from 2.500 the carb collapsed and I got AFR 18.2 the whole time, the engine stumbled bad and didn't accelerate.
So after that I changed the power valve to a 9.5 (standard version, the high flow version is on the way) and the engine accelrate much better and AFR was good. But I still have the small lean spot between 2.500 - 2.800 rpm, so I hope the 37 squirtet with the 50cc pump helping at his point.

My question is now. Should I go to bigger Jets on the secondary side and take a 8.5 or 6.5 high flow power valve? Or leave it like it is now on this side?

One note, I mailed AED for the air bleeds and some tech help, no answer after one week. I wrote Brasswell carburation too, they answered after 3 days. I'm disappointed by AED, before I got the carb they were helpfull by finding the right carb, but now when I need a little support there is nothing.

Grumpy · Apr 30, 2018

swapping to the 9.5 power valve vs the 4.5 power valve allowed the new (stock) power valve to open at the earlier point in the transition between primary idle vs secondary fuel supply thus the richer, transition
yes the larger accelerator pump and perhaps the blue accelerator pump cam will cover the lean spot in the transition.

http://garage.grumpysperformance.com/index.php?threads/holley-accelerator-pumps-cams.1790/

http://garage.grumpysperformance.com/index.php?threads/holley-annular-vs-down-leg-boosters.5229/

http://garage.grumpysperformance.com/index.php?threads/carb-tuning-info-and-links.109/

http://garage.grumpysperformance.com/index.php?threads/holley-carb-power-valves.1639/

55C150 · Apr 30, 2018

Thank you Grumpy. I read most of the links a few weeks ago. What I want to try is to put larger Jets on the secondary side to use a smaller size power valve.

55C150 · May 8, 2018

OK the 50cc acc pump is in, the 37 squirter too. The shoots are too rich now (AFR tells me 10.9 - 11.3 when the acc pump is activated), I will go back to 35 squirter. I still have the lean spot on higher rpm range. I got the bigger main jets for the secondary side and still waiting for my air bleeds. I also want to try to get two sizes smaller on IFR and the original size main jet on primary side.
So in my theory the idle is better adjustable and leaner but the range between 2500 - 3000 is richer.

55C150 · May 18, 2018

I'm still waiting for the air bleeds. I got the set screws for IFR, but AED gave me the wrong Information about the IFR thread size. They told me it is 6/32 but the 6/32 doesn't fit, so I measured the IFR's. They are 8/32, so I'm waiting again for the correct thread sized set screws.
In the meantime I was reading much about fine tuning a carb with the help of a O2 Sensor (wideband lambda) and how IFR / air bleeds work. Nothing really new to me.
I added a electric Fan on the radiator side, the flex fan is history now.

Indycars · May 18, 2018

Are you getting the set screws locally or from the States? Must be a pain if you are ordering
everything from the States, that's got to really slow things down.

55C150 · May 22, 2018

From Allstate Carburetor and another Ebay Shop called superflowcarbs from the States. I tried to get the set screws here, but no way. Same with blanks which I can drill by myself.

I got an Email from AED.
"
Markus,

That is completely my mistake sir. The HO blocks do in fact use an 8/32 thread for the IFR, while our Pro-Series blocks use the 6/32 thread.

I can mail you some restrictors if you have a difficult time locating them. Again, my apologies on the mix-up. Please let me know if I can help.

Thanks so much sir & have a great day,

Jeff Harris
AED Performance
Custom Orders & Tech Support
(804) 271-9107 Ext.17
PRI Carb Shootout Winners!"

I will see if they send me some bleeds.

Maniacmechanic1 · May 22, 2018

55C150 said:
From Allstate Carburetor and another Ebay Shop called superflowcarbs from the States. I tried to get the set screws here, but no way. Same with blanks which I can drill by myself.

I got an Email from AED.
"
Markus,

That is completely my mistake sir. The HO blocks do in fact use an 8/32 thread for the IFR, while our Pro-Series blocks use the 6/32 thread.

I can mail you some restrictors if you have a difficult time locating them. Again, my apologies on the mix-up. Please let me know if I can help.

Thanks so much sir & have a great day,

Jeff Harris
AED Performance
Custom Orders & Tech Support
(804) 271-9107 Ext.17
PRI Carb Shootout Winners!"

I will see if they send me some bleeds.

Its Nice when manufacturers write back to You.
Makes me feel good and proud of the parts I bought from them.

55C150 · May 23, 2018

Sure, we will see what they send me.
Today was a strange day. I installed a new electric fan in my fan shroud and got the idle air bleeds from the post office. After putting in the .068 idle air bleeds, I wanted to do a test drive, with e-fan and the new carb setup. I was rolling out the garage and shortly after that the engine stopped. I ttreied to start again but no way. After a few inspection I found out that my nearly new (350 miles old) Summit 110gph mech. fuel pump had quit. There was no fuel in the line, I disconnected the feed line and cranked the engine, no fuel.
I will check tomorrow if the pump or the pushrod is the problem.

Maniacmechanic1 · May 23, 2018

You can still Buy Mallory Comp 110 & 140 electric fuel pumps new.
What I like without breaking the bank.
Very reliable.
If bought used you want to rebuild it.
Rebuild kits sold on Summit Racing.

Comp 110 will support 400-425 Hp.
Comp 140 will support 500-550 Hp max.

Maniacmechanic1 · May 23, 2018

There is A Comp 110 FI.
can use with a carb and return regulator layout.
Electric pump is Big.
Support up to 850-900 hp.

55C150 · May 23, 2018

I am more the mechanichal pump guy, but I will have this as Plan B. You recommend these in the past.
I borrowed a Holley elecrical pump from a buddy if I can't fix it till friday with a mechanical pump.
I have to drive 700 miles this weekend for a car show.

55C150 · May 23, 2018

I need the tech details of this pump from holley. Can someone help me please. I can't found any information on the net.

There is a 977 2704A stamped on it.

Maniacmechanic1 · May 23, 2018

55C150 said:
I need the tech details of this pump from holley. Can someone help me please. I can't found any information on the net.

There is a 977 2704A stamped on it.

Its A HOLLEY EFI INLINE FUEL PUMP.
We Used to Call Them T-Rex Pumps.
Came with Mustang 5.0 Votech T & S trim Centrifugal Super Charger Kits.

Not a good match for your 55 Chevy with the AED HO Holley 4-bbl.

Maniacmechanic1 · May 23, 2018

Made by BOSCH that Holley Fuel pump.
Think its the 190 Liter per hour fuel pump.

Grumpy · May 23, 2018

55C150 · May 24, 2018

Thanks Maniac... and Grumpy. Lucky I asked, I had a bad feeling when I saw the pump.
Grumpy I read most of the links you posted in the past, thats why I use 6AN lines and a return line.

55C150 · May 24, 2018

I got a new EMail from AED, great news.
Markus,

I can do that sir, no problem. I’ll send some .031” restrictors to try as well as a few sets of blanks for you to experiment with. I’ll send you the tracking info as well once it’s on the way.

Thanks so much & have a great day,

Jeff Harris
AED Performance
Custom Orders & Tech Support
(804) 271-9107 Ext.17
PRI Carb Shootout Winners!

55C150 · May 25, 2018

So I fixed the fuel pump problem temporarly, I used my old one till I know which I want use in the future.
I changed the Idle air bleeds today from .070 to .068, big difference. The leanest spot I got at 3.200 rpm was 15.0 cruising speed. That was the spot where I got 17.2 before. On the downside is the range from Idle to 1.800 rpm, there I got rich numbers 12.3 - 12.6. I hope I get my IFR's next week to fix this problem.
I also changed the power valve from 10.5 to 8.5, the WOT is a bit too rich 12.2. I will try a 6.5 or the original 4.5 next week.
Is it possible to use different sizes of air bleeds in primary and secondary side of carb?

Hi from Germany

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