Does Holley still make a spredbore carb

[junkyardjeff]

I recently bought a 77 F150 with a 460 and the previous owner adapted a quadrajet to it and it had a vacumn leak,after taking it apart it has a spreadbore manifold and I need to know if Holley still makes a spreadbore carb I can bolt on without any adapters.  I do know where a 429 is with a 2 bbl intake and I have a nice Holley 500 CFM 2bbl if I cant find a carb that will work.  Jeff

[wayne petty]

where is the leak from....

did you change the gasket below the carb adaptor../  
the carb mounting gaskets are manifold to adaptor , then adaptor to carb...  putting the wrong one in the lower will create a huge vacuum leak.. sometimes an exhaust leak also on the intake manifold..


is the egr plate rotted out???


i have not searched far into the holley site...  they do show a spread bore but list it only for gm apps... there is probably not a kick down arm on it..

the picture i posted is the holley reman carb for the 460...

i think there was talk on a prior post that the holley 2bbl will bolt on with a flat plate made with a drill and a hole saw....

[junkyardjeff]

The carb spacer that was on it was not made for a EGR valve and looks to be made out of plastic,I looked at the manifold where a hole coming up through it for the EGR would be and it was not drilled so I am thinking it did not come with a EGR valve originally which is wierd since all 73 and up light duty trucks and cars usually did.  The manifold has a D6 casting number and looks like it has never been off so I dont know,I used the carb adapter to mount a square flange holley 600 CFM on it and elminating the factory looking spacer and it runs better and I dont hear that sucking sound now but it still does not idle like I want it and that adapter with the open space between alll the ports might be the cause.  They had the factory looking spacer plus the adapter and them the quadrajet so plenty of areas for something to go wrong,I am going to look for a factory carb that is in working shape or see if i can find a holley spread bore.  JEFF

[wayne petty]

check again for vacuum leaks...  even tiny ones will make it hard to idle


if it won't idle with a square bore ... it may not idle with a spread bore...

and... if you look for a replacement carb..  make sure there is no play in the accelerator pump shaft..    open the throttle half way and see if the throttle shaft rocks in its bores...     it is not the(black) wire one shown on the carb image ... it has a lever(silver) out the drives side of the carb top... that hooks to a rod up from the throttle linkage...

and ...is the power brake booster blown?     the one in my ford van was so bad that when i squeezed the vacuum hose with pliers the engine died...


wayne

[junkyardjeff]

I will check the booster and I am going to see what size jets are in the carb as it smells lean.  Jeff

[junkyardjeff]

I checked the booster and no leaks there so I checked the carb and it had 66 jets,what was left of my jet pack had 67 on down and 71 and up so I installed the 67s and it seems to be a little better.  Next week I will go to the speed shop and get 68 to 70 jets and play with it more,I should probably get a 650 or 750 carb or what is supposed to be on it.  It runs a bunch better with the holley then with the QJ  and now it has a choke.  Jeff

[wayne petty]

just one question.... where are the idle mixture screws set at.?

those have a great deal to do with idle mixtures through about 2500 rpms...

so if they are at 3/4 turn where most of them end up at... you might open it another 1/8 of a turn...

i wonder if the after market metering blocks are also made with course pitch thread..??

later model 460s used a holley 4 bbl 4150 model.. i wonder what jets they used... as that might get you closer... looking it up backwards...    

wayne...

[reborn55]

How many Holley spread bores would you like?

[junkyardjeff]

The idle mixture scres are a bit out from a 3/4 of a turn and this carb I got from a friend who got it off ebay as rebuilt but has had a couple issues,I should check the tune of the motor before going any farther as it could of been years since it had plugs and I know it still has the original plug wires but it runs alot better with the QJ off of it.  I am leaning towards getting the 2 bbl intake off the 429 in the junkyard since I have a real good 500 CFM 2 bbl and this truck is just a beater and I dont want to spend a bunch getting a good 4 bbl.  Jeff

[wayne petty]

429/460 2 bbl??     if it has a 2 bbl... it is more than likely a 400... looks the same..

i have a welding shop nearby with a iron worker with hole punch tooling...... they make stuff for me all the time.....   i have gaskets laying in front of me...   you should see the nice spring shackles i had made for the fairlane project...   half inch spacing...

i was even thinking about having them punch out one for my ford van 460...

i only have to countersink 2 holes for the rear studs which i will use flat head allens in through the bottom....

two would be simple...i not only have several 2 bbls.. i have an economaster 2bbl holley...  set up for ford...

wayne...

[junkyardjeff]

Yes its a 429 and yes it has a 2 bbl,its the only one I seen but I could also go with using a plate and making a adapter.  Jeff

[wayne petty]

for those with spread bore carbs and want to switch... this might be of help..

http://www.drbob.tqhosting.com/tech/carb/4350_compared.html

[junkyardjeff]

That spacer that was shown in that article will be ordered today,I could probably get the intakes cheaper but the time savings will make it worth the money.  Jeff

[junkyardjeff]

I ordered the adapter and its now 58 and some change,easier this way instead of a intake change.  Jeff

[reborn55]

If that doesn't work I have a couple of 6853 Holley spreadbores theat might work