4 barrel on a 292 straight six. Done it?

Hey guys,
 I put a 292 in my '64 with a 2 barrel on top. I was looking to see if I could pull a few more MPG out of her and went to a couple "stove bolt" sites. It seems we can get more MPG if we allow the motor to breathe better. There is a trick called "lumping" the heads where you get rid of a "step" in the exhaust chamber. I breeezed over that as it entails some head work that I don't want to do now but, they also say that a 500 cfm 4 barrel on an Offenhauser intake can help as well. It will help her breathe on the front side.
My question is have any of you done this?? I would be willing to give it a go but, I don't think it will fit in a gen 1 doghouse......unless the Offy manifold is much closer to the head.
IF any of you have put on a 4 barrel, please let me know about what modifications you had to do. If I have to cut out the dog house, it's not going to happen.
Thanks!

Check with Clifford Engineering, they are building my 250 w 325hp/ 400tq w Twin Weber 38/38's right now     Talk w Larry (951) 417-1161

https://www.cliffordperformance.net/

Awesome Truckin, thanks!!! But is yours a gen1?? My dog house is narrow. 3 dueces would be cool if I could tune them.

Mine is a 2nd gen and we are using 2 deuces and not 3....

Yeah, I'm not an authority on these big beautiful boxes but, I understand the Gen 2's are wider doghouses than Gen 1's. (???) They fit small blocks much easier. As you can kinda see in the pic, my Weber is right up against the side of the doghouse which is right up against my seat.
My thought of using 3 dueces is just to get more air flow. They were pretty adamant about "breathing" with these 292's, on those other sites. They were claiming from 18 to 26 MPG. I'm thinking the high end is exaggeration but..........good for him if true.
Thanks buddy!

Larry is saying 16 to 20mpg on my build.

I'd take that!!!
I MIGHT be getting 11.

A four barrel manifold and carb is not going to fit in a stock first gen doghouse. The offy four barrel manifold is patterned off the stock intake, just has a four barrel opening. Clifford manifolds are even larger and definitely will not fit without mods to the doghouse wall. Offy makes a dual and triple manifold for running multiple single barrel carbs. This is the way to get more cfm without cutting the stock doghouse. None of that is going to improve you mpg on the 292. You could get an improvement by swapping in an OD transmission

depending on which 4-barrel, maybe. offy is same as stock so measure from center of carb as a reference. the Clifford intake is wider, I called a few years ago but forget the measurement. keep in mind the carb is turned 90. both primaries either towards engine or both towards seat, whichever allows more room. my dual webers are backwards as it allowed more clearance and shorter cable from the front. if it 'almost' fits, a spacer under passenger side of crossmember will lean engine and never notice it. I had mine that way with the smaller carbs but the backwards 32/36's fit fine.

Thanks Kooky. I was pretty sure a 4B. would not fit. I was fishin to see if anyone might have found a trick or two but, it did not seem physically possible.
Rightly or wrongly, I'm a little apprehensive about multi carbs. I don't have any experience with them except for duel carbs on a VW. But if someone, with the knowledge, knew of a good, higher MPG set up, I'd be all ears.
I do have a 700R4 on the back of her. It's obvious the barn door on the front is not doing us any favors but.........it's such a cool barn door. LOL

Here is a couple pages from J.J. with quite a bit of info on 292's. I found it very interesting. They talk about lots of ideas including "lumping" the heads. https://www.jalopyjournal.com/forum/threads/292-get-best-mileage.263255/ I thought you guys who are interested might enjoy the read.
Thanks for the help gents!!
Merry Christmas!

Skulptorchaz wrote: I was pretty sure a 4B. would not fit. I was fishin to see if anyone might have found a trick or two but, it did not seem physically possible.

maybe there is another member here with a first gen and 292 that has tried several different carbs and done extensive research?

Well, I guess not. I thought I would let this thread go for awhile in hopes maybe someone would have some knowledge, jrinaman, but no luck. I'm pretty sure it just won't fit, even with some custom fabrication.
Thanks guys!!

but I gave you several tips! the centerline of your current carb will also be the centerline of the 4 barrel with an offy intake. knowing the distance from centerline to doghouse allows you to calculate which carb and how its mounted. spacers under the passenger side crossmember can easily gain you another inch. you would also have to offset your air cleaner or just run cold air with a filter at the inlet. an edelbrock with primaries away from engine doesn't overhang intake at all and reversed, you would only be dealing with vacuum lines. https://static.summitracing.com/global/images/prod/large/EDL-9900.jpg?rep=True

And I TOTALLY appreciate the help buddy!!
The center of my carb to the doghouse is 3.25''. (max) I still run the mechanical linkage on the 2 barrel and it barely clears the dog house. Are you suggesting I need to run a cable? I'm guessing the manifold requires a person to spin the carb 90*. (That kinda bites if I have to run some sort of cable as I just put a bunch of time straightening out and modifying the present linkage.)
Are you saying spacers under the motor mounts? ("cross member")
The air cleaner would just me a "fab thing". I can get creative there.
I wonder if anyone would have any pix?
Thanks again buddy!

the original monojet used a bell crank to compensate for the 90 degree turn in linkage. you could do the same but a cable is so much simpler. I am using a pusher cable. it has been a few years since I looked at installing a 4 barrel, I went with dual webers for other reasons, not for clearance. I have seen the 4 barrel installed on 6's front to back but the are intended to be turned 90. you may not need spacers but you will need some clearance as the carb will smack off the doghouse on decal. the offy 4 is a stock type intake that accepts the 4 barrel. your heat plate under the stock intake is almost as big so the intake will fit. the doghouse slants in slightly so that is the clearance issue. I have an edelbrock at the shop, I will get some measurements today but my calculations years ago showed me it would. I never actually installed the 4 barrel but have had several different carbs and linkage set ups so know a few tricks.

Here are a couple pix of the mod I did, to the lid, to get the radiator to fit. (I went larger for the 292)
I am hurting for space but if I don't have to cut into the lower part of the dog house, I would be OK with modifying the lid some more.
I'd like to find an offy to just try first. As far as the carb, I'd like to also find the best fit. I have read where a 500 or 380 would work but, that was on a car or truck without clearance issues.
You can see in the pix that the air cleaner is a bit tight. Something else I need to rectify but, if I go 4 barrel, it's a moot issue.
Thanks again!!!!!!!!!!!!!

I`m running a 292 with offenhauser intake and carter competition series 500cfm afb 4 barrel carb with no clearance issues in my 65

Awesome!! Any chance you could post a picture or two?? I'll start looking for that carb. if that one fits well.
I appreciate the heads up!

P.S. do you ride a Panhead w suicide?? I ride a '46 Knuckle with suicide I bought off of Sunset beach in 1980.

suicidepan wrote:I`m running a 292 with offenhauser intake and carter competition series 500cfm afb 4 barrel carb with no clearance issues in my 65

I would like to see pics of your setup, including the throttle linkage. I never knew a 4 barrel carb could fit.

Skulptorchaz wrote:Awesome!! Any chance you could post a picture or two?? I'll start looking for that carb. if that one fits well.
I appreciate the heads up!

P.S. do you ride a Panhead w suicide?? I ride a '46 Knuckle with suicide I bought off of Sunset beach in 1980.

Sorry for the very late response. Here are some bad pics of the 292 with offenhauser 4 barrel in take with carter competition series afb 500cfm carb. My van is a 1965 and there are no mods to my dog house. I`m also running a all aluminum radiator for a 5.0 mustang for cooling which works excellent. I did have a suicide shift 55` pan up until a few years ago, good guess by you.

Space Truckin wrote:Larry is saying 16 to 20mpg on my build.

That would be a neat trick on one of these aerodynamic bricks. Let us know how it turns out.

Skulptorchaz - BTW when I bought my 66 last year I drove it home from Phoenix to San Diego, 60-65 MPH the whole way and I computed 14.5 MPG based on fuel purchases. It's a non original 250 six / three on the tree with 1bbl carb and stock air intake/filter. So maybe 11MPG with a 292 isn't too far off from normal? The aerodynamics of these vans, it's like pushing a billboard down the road.

I`m getting 12mpg with my 292 consistently

,,,,rear end ratio affects speed, power and gas mileage,,,,,,the 12 bolts are 3:73 and 4:11 ratios,,,,made for power, not speed or gas economy,,,,,,,,,,,the 10 bolts, 3:36 are made for speed and better gas mileage,,,,,,

Mine has a 4.11 rear end