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-   -   Need help RB Holley 465 issue (https://www.rx7club.com/1st-generation-specific-1979-1985-18/need-help-rb-holley-465-issue-942802/)

zkeller 02-20-11 07:43 PM

Need help RB Holley 465 issue
 
First off I am at whit's end and am willing to pay someone to help me out. :)

I have a Racing Beat non-ported intake/carb kit on my non-ported 83. Car sat for a year as I finished it up. Hooked up the wideband and am seeing a very lean condition from off idle and through the driving range, especially under load. I am seeing AFR in the 17:1 range, 20's on light load!

Can anyone help me out?


I have verified and done the following:

Fuel pressure is solid at 6PSI. I also checked it while driving. New high-volume fuel filters.

Timing is dead nuts on. New plugs, wires, cap rotor.

No vac leaks. Sprayed carb cleaner around everything and no engine RPM change.

Float bowls are set. Idle mixture is set.

Completely freshened up the carb and still have the exact same issue as before. Carb looked like day one on the inside.

Changed to a larger accelerator pump squirter.

Fresh fuel

Thanks in advance, I am at a loss.

zkeller 02-20-11 07:51 PM

On a side note, I thought that the RB modified 465 had the power valve blocked off? When I took the carb apart, the power valve was in place.

Also checked compression and it is +/- 110 PSI

zkeller 02-20-11 09:17 PM

Jets are #49

drifting in drifting 02-20-11 09:19 PM

Its a holley enough said

84stock 02-20-11 09:26 PM


Originally Posted by drifting in drifting (Post 10479900)
Its a holley enough said

Don't hate what you don't know how to tune :)

Jets seem too small, stock a 465 comes with 57's. Go to a bigger jet size and replace the power valve with a 6.5 while you are in there. I would try a pair of 55's and gradually go down. Always start rich.

I run a 750 double pumper on my supercharged 13b and it runs flawlessly. However, took a little time to get there.

Being an old dog, carb's aren't intimidating to me at all. Give me a laptop and a standalone and I'm lost :blush:

84stock 02-20-11 09:27 PM

I even have my timing curve dialed in perfectly using ford motorsports advance springs in the distributor. These springs date back to the sixties and you'd be damned if you could find any today, worked just right for my application.

zkeller 02-20-11 09:34 PM


Originally Posted by 84stock (Post 10479908)
Don't hate what you don't know how to tune :)

Jets seem too small, stock a 465 comes with 57's. Go to a bigger jet size and replace the power valve with a 6.5 while you are in there. I would try a pair of 55's and gradually go down. Always start rich.

I run a 750 double pumper on my supercharged 13b and it runs flawlessly. However, took a little time to get there.

Being an old dog, carb's aren't intimidating to me at all. Give me a laptop and a standalone and I'm lost :blush:

Thanks for the info. I am the other way around. Give me a laptop and FI and I am good.

drifting in drifting 02-20-11 09:47 PM

holley are good if you want to mess with it but runn a predator on that and be done trust me

drifting in drifting 02-20-11 09:50 PM

Holleys dont hold up when you slamm them around alot like in mudracing

Donovan N. 02-22-11 10:35 PM

Look up angel's motorcycle shop on market street (I think),near miles mufflers in york. he used to work rotaries and drag races them I think. so he might be able to help

RX-7 Chris 02-23-11 10:21 AM

I agree with 84stock. up the jet size.

teddyrx2 02-24-11 02:57 AM

49's are way low that is why your seeing such a lean read.

zkeller 02-24-11 07:39 AM

Thanks for the help guys. Put 54's in and the car runs great.

84stock 02-26-11 09:45 PM

good to hear!

Pitch 04-26-11 08:37 PM

79 RB Holley setup
 
I recently install a RB Holley 465 on my SA. Also installed a carter pump from Jegs, 6-8 pounds 70- GPH. Car is running good but I'm concerned about the fuel pressure. My gauge says the the pressure is 3 lbs? If I crimp the line after the gauge the pressure goes to 6 lbs. I tested with another gauge and received the same readings. Can someone help me understand why my fuel pressure
is 3 lbs at idle? (800 RPM)

I called RB and they have not seen this issue before. RB said that I needed a fuel pump pushing 6 lbs at 20 GPH min. The Carter pump I installed is a 6-8 lb rated at 70 GPH. I should have plenty of flow but it seems like the carb is eating the gas quicker then the fuel pump can deliver.

Your input would be appreciated.

RotorMotorDriver 04-27-11 12:07 AM

Did you install a pressure regulator? Where is the gauge taking its reading from? Your fuel system should go from the pump to a regulator (with or without a return line), then to the carb. The pressure reading obviously should be taken after the regulator.

If the fuel pressure is wrong, the carb will be affected while driving - whether you can feel it or know it is another issue.

~T.J.

RX-7 Chris 04-27-11 11:11 AM

I was running that same pump on my other car with no problems. I also ran a holley FPR with gauge. It always sat right at 6lbs. No return line.

Could your problem be the filter?

j9fd3s 04-27-11 12:08 PM


Originally Posted by 84stock (Post 10479913)
I even have my timing curve dialed in perfectly using ford motorsports advance springs in the distributor. These springs date back to the sixties and you'd be damned if you could find any today, worked just right for my application.

http://www.summitracing.com/search/M...dvance+springs

Jeff20B 04-27-11 12:15 PM

I wonder if GSL-SE springs would suffice?

GSL-SE springs with a 12A (straight slot) shaft. :)

j9fd3s 04-27-11 06:45 PM


Originally Posted by Jeff20B (Post 10593599)
I wonder if GSL-SE springs would suffice?

GSL-SE springs with a 12A (straight slot) shaft. :)

when i order springs for the Tr3 (something is broken in there) i think i get a kit, that may work too


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