I built a 302 ho motor and am having a problem with getting it to idle, I put an edelbrock 650 4 bbl and it surges and won't idle. i pulled the plugs, new plugs, and they were black which means its running rich. I took the pcv valve off to make a vacuum leak to see if that would help it from being to rich and it helped a little but still can't get it to idle. Can anyone give me any ideas on what the problem could be or tell me the best carb for my truck. Thanks and it's good to find a forum on Fords.

 

650cfm is a little large. Most run a 600 cfm carb, but a 500 is about right. You will have better response and driveability. Make sure you are using the HO firing order if it is truly an HO cam. Also download manual from Edelbrock website for proper adjustment. The jet and spring kit they sell is very useful for tuning.

 

Thanks gfw1985 i kinda thought the 650 might be a little much,the firing order i am using is 13726548 I think its the same as a 351 w. I'm going to get another carb for it, I think I'll go with the 500 and see how it works. I'll let you know how it works when I get one.Thanks again.

 

Welcome to the forum! (we need more bronk owners), enjoy the site. Did U know there's a local chapter for your area. Might B nice to connect w/ford owners locally. When I did it was fun and helpful. Meanwhile, keep talkin - plenty of guys for on-line ideas right here...
(U got a nice rig, last yr for the removable window frames I think).

 

Thanks Chrlsful, I will look into a bronco club after I get mine running right and do some other work to it like restore the under carrage and the interior. I was going to buy a 500 cfm carb but I found a autolite 4100 in my dads garage. It was for his 64 t bird with a 390 but didn't work well. I just rebuilt it and am going to try it out tomorrow. What size jets will work best for my 302 ho motor. I think the ones in it might be to big and I couldn't see what size they are, getting old really sucks, so if it needs jets what would be the best size. Thanks in advance, Lynn

 

"...getting old really sucks..."
Yeah, 's proably Y it's so hard 4 me to get a good job any more -
or
did U mean the carb?
8^0
I was thinking if U connected w/the Local Chapter you could get alot more local (non-virtual) helpful help & get some comradeship as well!
I'm not sure how the 4100 does w/a 302/5.0. I'd hafta go over to our form on those engines to C.

 

Thanks, I'll check that out

 

OK-
I put the Q out on the forum I mentioned & got some responses. See below.
If U want go to the post "Q from over on the 66-77 Bronk forum" on that forum & PM 1 a da guys for more info. Get to the forum by going to the top of this page - the above horizontal white (not blue) line just below the top pic & click on "Forums", scroll down to "List", scroll thru that when it lists them out and open the forum (has ur motor in the list of topics). When that opens go to "Q from over on..."
********************
looks like these carbs were available in 2 different sizes, lots of good info and ways to ID what you have here.. (this wuz a link on the other forum) Autolite 4-barrel carburetors | Hemmings Motor News
Paul
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If the 4100 is from a 390 engine, it is probably the bigger, 1.12 venturi type. I tried one of these on my 260 years ago, and it was definitely too big as there was less power off the line compared to the old 2V carb. Even though a 302 is bigger than a 260, that engine still will be much torquier(sp?) with the smaller, 1.08 carb. The 1.08 is found on regular 289-4V as well as some later FE engines.

As for the jet sizes, this is not necessarily proportional to engine size. It is matched to the venturi size and other features of the carburetor, so find out what the stock sizes for your carburetor are, and use those for starters.

Early 4100s do use Holley type jets, they changed to the Ford only type in the very early 60s.
Beanscoot
_____________________
Jet size is proportional to engine displacement to a certain degree. With a 390, it's going to flow more air thru the venturis than a 302 will. So, yes, he'll have to jet it down a size or two for a 302.
bad457

 

I found that the 302 engine I was trying to get going is trash, so I've started putting a 351 w efi motor from a 1995 ford f-150. I'm wondering about what wiring and sensors are not needed to make this engine work and I'm going to use original harness, are there any suggestions that might make it easier.

 

Hi Lynn,
As soon as I saw yer 5th post I thought about 2 ideas: 1) hood clearance issues. U better measure both (hight of intake top from rails/mount in truck to hood, how much room U have from same place in bronk to inside of hood) because there's not much room in the bronk.
Let's C if anyone stops by here w/an answer because I like a lill more period correct & 6 cyl. so don't have the info. (I DO like the efi idea for ease of maintenance, tho). If no 1 duz U can go over to Classic Broncos because I've seen writ-ups (or U could start yer own thread over there too). Just watch out, there's some pretty big egos there (read - some people like to 'slam' others, I know from personal experience).
One of the mods the vehicle (2 me) is just screamin for is a 1 inch body lift. That's personal opinion but many agree. I'm not sure if it's enuff 4 this instal??? The earlier car engines (TBird, 'stang, Lincoln) fit easier. Depending on what application U have in mind 4 the bronk I would consider SOHC (truck) rather than DOHC (more car like) as well...

2) IS FIgURE THE APPLICATION OF YER VEHICLE (o0OOPPps, sorry 4 the caps - but hey they're @ the right time) FIRST before designing (thru lots of research) what will get you to the best point for that use. Then stick w/what you've decided (again thru some hard work) so a dream is solidified. It will B 1 in which U will more easily stay engaged over the tough build period. I've see lots abandon 1/2 way thru, or as they change on the way - the result is a hodgepodge of parts. A bronk is already multi-purpose so heads off in that direction a lill 2 start. Ie "I want a street vehicle I can occasionally go hunting in." is not enuff. How many mi per yr on rd/off rd, what ratio, how much weight will B carried to hunt, how far off rd, what gradients & conditions will B encountered, do U want more of a racer or show vehicle and on and on...
Hope I'm not being patronizing, that is not the Q U asked...

 

Thanks Chrisful for your input I really do appreciate it. I haven't been on here for a while, been working every spare minute on my truck, now that my sons back from Colorado for the winter I have him helping me and him being only 22 yrs old I have to admit he's a very good mechanic.
So here's whats going on with my project to date. We took the wiring harness out of the 94 f150 donor truck and are using it in the bronco, I think $500.00 + is a little steep for a custom harness. We got the engine in the bronco after fighting it for a while and my son figured which wires we needed to make it run and after wiring it like he said, we didn't have a wiring diagram to go by, it fired right up and is running like a raped ape.
I had my doubts but he really pulled this out of the fire. We did away with almost every thing that was vacuum and most of the sensors and we also put my headers on because the factory exhaust wouldn't work. No o2 sensor and no egr valve, we plugged the spare vacuum lines up and it runs amazingly good.
I thought this 351w with efi was going to be scetchy before we started because of all the input I was getting from some other sites, mustang forums and other truck forums saying you have to this and that but that was not what we found to be true. Everything off the donor truck worked fine without having to replace anything except i had to put on a inline fuel pump and remanufacture my radiator hose to the other side of radiator since it has a oil line that goes directly into the bottom hose and I had to use the factory bronco radiator and we used the bronco starter cause the 5.8 one was offset and wouldn't work with the flywheel off the 302, which we put in the 351, the 351 had an automatic and I had a 3 speed in the bronco.
We're just finishing with the cooling system and fuel and should be driving it today or tomorrow. I will post some pics of it soon. Oh and your right it sticks up way higher than the hood, but it looks like it means business. Can't wait to have some fool pull up in a chevy and think he's bad, make my day sucker fish.
Its going to be a nice 1969 fuel injected bronco when I get it all fixed up. Thanx for your input. Lynn

 

Hey Lynn,
Nuttin like a youngin to do it...
Lemmie No if U got nowhere 2 get a scoop or other apparatus for the "too tall motor".

 

"...any suggestions that might make it easier..."

U could go to classic bronco dot com. they have many build threads 4 just what U R doing

 

Thanx again, I'll check it out. Fired it up Again and again and it is running great. Had to refigure the fuel lines and theres alot of little stuff that has to be done but so far we're doing pretty good. Only problem now is it's running a little rich, so it won't pass smog but I can use a address out of town that doesn't need smog tests. There's always a way to get around some things. Need to install power brakes and steering and it will be ready to get out and tear up some desert. Lynn

 

Well got it registered today and fixed exhaust and got the brakes bleed just need to make air cleaner set up and I can drive it legally. I'll post a couple pics soon. Thanks for every thing, Lynn