Technical Spreadbore carburetor for 302 Ford, what should I be looking for?

Got this one hanging on the peg board if you dare give it a try. Looks like you will need to get creative on the linkage side.

 

I appreciate it, but reached out based on Steve’s reply about the linkage for the transmission, after a look, seems after 20 or so years tge linkage is not where I thought it would be. Who’d have thunk? Lol.

When it cools off, I gotta get the numbers on the Holley I have, not wanting to run it, @carbking mentioned in another thread about idle issue with adapters.

 

Like to hear more about the idle issue with adapter.

 

4360 holley 450 cfm works good on a 283-305

 

My guess would be eddy effect under the carburetor base plate.

 

^^Thanks, I'm following all this

 

This is a new one on me, I never knew Ford played with spread bores.

 

If you have idle problems with the 4 hole spacer, swap to an open plenum style. That's what I had on my Street master and I had no issue.

 

I personally don’t know. In a thread****led “rebuilding a SBC”, fella is going through an engine to run for display purposes. The use of an adapter came up, I commented along the lines of “it’s just going to be for display” and Jon (Carbking) replied about idle issues with the adapter.

Edit: on the last page in this thread are Jon’s comments.
https://www.jalopyjournal.com/forum...evy-350-rebuild.1287837/page-13#post-14937468

 

Kind of depends on the manifold design, and the adapter design. If the manifold just has 4 holes in it, and the throttle blades are not anything like directly over the holes, adapters don't work so well. but if it's open, then they're usually OK, as long as the area under the throttle blades is open, not restricted.

at least that's my take on it.

 

Sounds reasonable.
Thanks

 

I checked the numbers on mine (80508-3) and it is a 750 according to Mr. Google.
Which means all 4bbls I have here will be too much carburetor for this engine. I sent Jack a PM and will try to work something out with him.

I’ll get the Summit or Lokar kickdown, as when I was out back I see (after 20 years) I don’t have the one that was on it anyways.
Thanks all!

 

@Budget36 , here is a Ford/Holley spreadbore for sale,
https://www.jalopyjournal.com/forum/threads/lime-works-turn-signal-switch-misc.1298223/
Near bottom of ad.

 

Thanks, sent the fella a message.

 

Holley Economaster carb, List 4360, 450 cfm.

the Holley manifold in question is a Street Dominator, Z-Series.....Z-Series denotes the divider in the plenum and the cross connection intake passage that connects the two rear intake port runners.
They had SBC and SBMopar versions back then too, late 1970's-early 1980's time frame. Turns out the divider gimmick doesn't really help and Holley dropped it after just a few years.

 

Unless this Holley L-7455 has the proper linkage for your C6 transmission, as suggested above by carb king, you should probably pass on it.

 

Fella said he had it on a gm 305. Let me message him back. Thanks.

 

But as mentioned before, a lokar cable could be used on a Rochester, could it be used on the Holley?

 

Yes on the cable, but the throttle bracket on the carb, must have the cable connection at the EXACT correct location.
I'm not sure where that exact correct location would be when using a C6 transmission, with a Chevy carb.
I hope that makes sense.
@carbking , are you able to help with this?

 

No - I am sure that, with a lot of trial and error, several folks on this forum could make this work.

Me, I am too lazy

Carter TQ 6568s, Rochester Q-Jet 7040286, and Q-Jet 7040288 should have the correct arm in the correct place.

Why borrow extra work?

Take a look at the second line in my signature block.

Of course, one could always ditch the dogmatic transmission, put in a standard transmission, and run any Q-Jet they had on hand. This probably easier than fabricating an arm, and making it fit exactly.

Jon

 

Jon, thanks as always for keeping us pointed in the right direction.