Thinking about a spreadbore Holley.
I’m still having quadrajet issues.
Ram air clearance.
If I buy a square body with adaptor plate it may be too high for air cleaner clearance?
Are spread bores any good? I heard no from the guy that built my quadrajet that still dosnt work well,
maybe I should not be listening to him at all.

 

I've never been a fan of the spreadbore Holley carb. I prefer the squarebores.

 

Don't listen to that joker! If he says spreadbore carburetors are NO good then he shouldn't be rebuilding Qjets. What troubles are you having with your Qjet?

 

X2 as most other things that are rebuilt properly Q-jets work well. I going to find out how to perhaps change the primary and secondary metering rods on my 800 CFM currently on the 400E.

 

won’t stay running unless high idle 800 plus
when put in gear I have to tap the gas or it will stall.
not dripping any fuel lGloat set at 1/4
look to me like air horn is warped
I tried doubled gasket still same issue.
changed fuel pump to a stock carter I had too much pressure before.
i also filed down the air horn alittle to make flatter, but still not perfect.
I can drive it but when coming to a stop it wants to stall I have to tap it also on take off.
running timing at 12-13 base and points dist
set at 30
thanks!
this is a 68 455 with c heads, carb and intake stock manifolds divorced choke which does not rise to open so always open.

 

If I buy a square bore Holley with an adaptor plate will it be to high for my Ram air?
or is the Holley lower to begin with?

 

Did you measure the fuel pressure? Several years ago I bought a new pump that put out too much pressure, brought it back to the parts store and exchanged it for another, and that one put out too much pressure as well. Must have been a big batch all made incorrectly. I ended up installing a pressure regulator.

 

No, when I was taking The line off the carb with the orig pump it would spray 1-1/2 feet away
the new one trickles out slow and I know what guys are gonna say but it definetly is low pressure now like 4-6

 

My 70 455 came with a Holley 6497 which was a spread bore direct replacement for a Q-Jet "back in the day". I threw a rebuild kit in it but never could get it to run with a sh*t. I'm back to a Q-Jet now and relatively happy with it.

 

Really, wow

 

If you want to give it a try I might still have the Holley. If so, $25 + flat rate shipping for another $20 will get it to your door and you can screw with it.

 

Here is my air horn gap


Side shot pass side

 

The QJet on my 1970 Supreme was similar to that - too many gorilla mechanics cranking down on those front two bolts when installing the carb. I doubled up on the air horn gasket, and while the gaskets would get damp with fuel, it didn't affect the way the engine ran at all.

Then in the early 2000s I bought a reman QJet for the convertible and it came with a very thick air horn gasket. I contacted Holley tech line (it was a Holley brand raman carb) and they sent me a couple of those extra thick air horn gaskets. So there are thick gaskets out there to address the QJet air horn warpage.

 

yeah I put two on seals nice

 

 

Heres a great deal on a 780cfm spreadbore vacuum secondary

https://www.facebook.com/groups/1411...10479552422682

 

Think i can use that style? looks like electric choke

 

Electric choke is simple, one wire hook up.

 

yeah that’s what I mean lol
also I think it’s single feed? Which I like better than dual

 

No, its a dual feed, but there are a lot of different dual feed set-ups available that will simply connect to your hose from the fuel pump.
You could also buy one with a port to attach fuel pressure guage

 

It actually is a Single Feed.
confirmed by the seller see the pic of the fuel line.

 

That seems to be a list 7010. Although the primary is smaller than the secondary it will not fit a spread bore intake (qjet). It has center hung bowls making it a dual feed. The line out of the front bowl is a vent for emissions. I believe these were replacement carburators for ford products.

 

i guess will see I don’t mind the dual feed.
and if I need an adaptor plate so be it.
I just want a working carb.

 

Another option is a 750 Street Demon, it will bolt on without an adapter.

 

really?

 

Yes, pretty sure someone used it on here with an OAI setup. It is a 3 barrel, it fits square and spreadbore manifolds. It is heavily based off the Thermoquad with a bunch of improvements including an Aerospace Polymer main body instead of Bakelite. Also available in all aluminum. Pretty sure it only took minor mods to put it on and the air cleaner fit.

 

Here you go, in this thread, one guy installed in on a W31, he used an adapter which sounds optional, another guy had it on his 69 442 in the same thread. https://classicoldsmobile.com/forums...t=Street+Demon

 

Thanks good read, a lot of technical stuff I didn’t understand l,but yes they used adaptor plate and liked the carb.
Running good lately go figure