carburator talk

[scout man]

Carbs are something I dont know a ton about, but a recent thread got me thinking more about them. I have needed to do something with my carb for a while now, but I am not sure what to change to in order to accomplish what I want. My current carb is a 2 barrel Holley. I have been keeping my eyes open for a while for a 4 barrel intake for the scout. One of these just popped up for a good price, but I caught in the other thread that a 4 barrel might not be the best direction to go. Should I get this or not? What would you guys recommend for a good off-road carb?

[Brody]

Motorcraft 2100 style carb. Your 2 barrel Holley is fine, too. You may have to replace the needles and seats, maybe the metering rods and set the float bowl height, all accomplished with a $15 off road kit (Summit Racing for starters). Me, I would stick with the 2 barrel Holley since you already have it and it is a decent carb. You will be able to get that running as good as you can any other carb on the market. You would be wasting time and giving yourself headaches sticking a 4 barrel on an IH engine, much the same as you would be on an AMC 360, even if you have an RV style cam in them. You can get away with a 4 barrel on Ford and Chevy engines wheeling if they are tricked a bit, but they are pretty much a PITA unless you have a built motor. You simply do not need a pissload of gas when you wheel....

[scout man]

ok, thanks for the info. Problem I have right now is the stalling when I am on certain angles. I am sure it could probably use some attention though.

[Patrolman]

Any 4bbl for the Scout isn't going to necessarily resolve that issue. The problem with the Scout 4bbls is only the factory manifolds can be used. There are no aftermarket. That really limits you to the factory 4bbl carbs. Also, the 4bbl was only offered for the 345 and 392. Never offered for the 304, and can't remember what you run. There were 2 manifolds for the 345 and 392. There is a square bore, where all the barrels are the same diameter. Literally looks like a square. There is also a spread bore. 2 smaller barrels as the primaries, and then when you get into the throttle, the 2nd pair are larger. The idea there is that you are using smaller barrels, and in theory less fuel at part throttle. When you go full throttle, you should have the same if not more air flow since the 2nd set is usually considerably larger.

Where does all this leave you? Personally, like Pete said, stick with what you have unless you need more power. Consider an EFI kit somewhere down the road if you want to avoid stalling on angles. Or propane injection.

[scout man]

yea, I would do EFI eventually, but its really not affordable or realistic right now. a year or so ago I saw an EFI setup on CL for a great price, and I have been kicking myself ever since for not buying it. Oh well. I wont go propane, as its too hard to refill, and I drive it on the road too much.

Any of you guys big carb tuner types that want to talk me through some of this?

[Brody]

This may help out Steve. I am not a big carb tuner guy and it has been a number of years since I messed with tuning a carb. You are dealing with some small parts (the main issue) but not a lot of them and, for the most part, you don't have to take the whole carb apart. I managed to do this back when I thought (and approached) a carb was like a watch, and was freaked about taking one apart. What I did was to get the 'off road kit" an old white sheet and a desk light and just did it on the work bench. If you have messed with a few, you can actually do this on the rig, but risk dropping **** down the bore of the carb...Some of these deal with 4 barrels. 2 and 4 barrel carbs are set up pretty much the same way..

It is also pretty hard to mess up the meter rods and seats if you have to put new ones in. The float bowl adjustment is easily done with a 5/16" drill bit.

http://forums.off-road.com/jeep-short-wheelbase/232139-holley-carb-s.html

http://buyearls.com/data/Products/Technical/R7849-2.pdf

http://4x4mecca.com/tech_article/holley-truck-avenger-tips-roading

http://www.off-road.com/trucks-4x4/review/ford-f150-holley-carburetor-jetting-tips-21665.html

http://www.jeepforum.com/forum/f8/fine-tuning-holley-978551/

Hope that these help.

[Popsgarage]

Steve, fuel injection doesn't have to be expensive. Junkyard source yourself a '86 to '91 Chevy TBI setup from a pickup. Grab the throttle body, harness, computer, and all of the sensors. The most expensive part of the swap will probably be the plate to adapt the throttle body to the manifold and the computer chip to make it run with your engine specs. Junkyard pieces might cost you $100 to $200 and the Howell Engine Development stuff will run you around $250 to $300. Much cheaper than the complete Howell kit. They source most of their stuff from wrecking yards in their neck of the woods anyway! You might not even need a chip depending on how it runs after conversion and you can build yourself a adapter plate as well. PM Pancake (Mike) about how he did his. It runs pretty well!

[scout man]

yea, I have read all that before, just not sure its in my knowledge range right this moment. I'm not so good with all the computer stuff. I think what worries me more than anything is the computer part and getting it all dialed in.

[Popsgarage]

As long as the displacement and manifold vacuum are close to Chevy specs, it'll run fine. Yours should be close and that particular setup is as easy as computer control gets.

[Brody]

Here is that carb article I was trying to find:

http://www.ih8mud.com/tech/carter.php

They are all pretty much the same animal...and this is a really straight forward article.

[Molley]

i have run all makes of carbs and tryed almost all the off road tricks to make them run at off angles .. all failed , some run better then others but none run like injection . i put the howell kit on and its all very straight forward and labeled very well.the 4 things i had to change .i had to block off mech fuel pump,install elec pump run a return line back to tank, and o2 senser in tail pipe,and install engine light on dash and there is no dialing in , its all controled by a simple brain box that pulls in, howell guys are very good to work with if and question come up . o yea i had to change air cleaner to clear hood . took less then day to install ;. hope that helps a little

[scout man]

thanks! I actually ended up picking up a EFI setup from a Chevy Suburban - or will be once I have the money. It has been set aside for me. So I will prolly get in in a few weeks, but sit on it for a few months. I have enough other crap being worked on at the moment!

[Popsgarage]

Good choice Steve. If you need a hand, let me know!

[scout man]

oh, I plan to! :D I intend to invite a bunch of you gear-heads over and buy some beer an make a day of it. I feel a bit out of my league on this one and would love to accumulate some more knowledge. If you get enough of us in one place, you are bound to find some knowledge, right?

[Popsgarage]

Only aftermarket part you might need will be the intake adapter. Call the guys at Howell. Really nice, knowledgeable guys! They will answer almost any question you have! And I'll definitely be there!:thumb:

[scout man]

Only aftermarket part you might need will be the intake adapter.
yea, I think thats all I will need too. That and a fuel pump, since I dont get to steal that off the donor rig. He is keeping it. and a weld on bung for O2 sensor... and whatever else pops up in the moment!

I will let you know when it happens!

[Popsgarage]

If you're buying a pump, I'd recommend a Walbro pump from here.

http://www.autoperformanceengineering.com/html/pump_faq.html

[Brody]

I am running a Wabro with my SC set up. No problems for 6-7 years and just checked it again last year.

[Popsgarage]

Yeah, the Walbro pumps are really good stuff!

[scout man]

good to know! thanks!

[Hypoid]

Only aftermarket part you might need will be the intake adapter.I saw some weird aluminum plate on top of a 2V manifold today. It was on a 1991 Full Size Jeep, made me think of this thread.

[Patrolman]

Some helpful links:
http://bobsbadbinder.com/project-tbi-fuel-injection-fixed/13/

http://www.binderplanet.com/forums/showthread.php?t=57483

http://www.affordable-fuel-injection.com/extreme-4x4-flex-fuel-scout.html

[Patrolman]

And some videos:

http://www.youtube.com/watch?v=w4Ioe94NSeo

http://www.youtube.com/watch?v=7jmPnyhPeuo&feature=related

[Patrolman]

And this is the best I have found so far. Now I am thinking about doing mine. I get tired of messing with the carb!

http://www.justih.org/Binder-Bench/forumdisplay.php?f=21

[scout man]

well, your welcome to come help out with mine when the time comes! Its always easier doing it the second time around!

[Popsgarage]

A couple more distributor conversions.

[scout man]

hmmm, I am thinking you meant to put a link in there? :D

[Brody]

Hey Guys

If you find Scout or IH links to stuff, would you mind adding them to the IH make and Model section section so that everyone else can benefit from you research/knowledge? And by 'everyone', I don't simply mean folks on the forum. A lot of people come to this site for TECH information when they are trying to find stuff and the more comprehensive the TECH info here is, the less BS searching people will have to do. And, as I am sure you have found out, trying to find information is tedious....

Thanks in advance. I already took care of the other IH/TBI stuff posted here and got it into the IH section this AM.

[Popsgarage]

For some reason the articles wouldn't post as links. They're all on http://www.binderplanet.com/forums/showthread.php .