Inliners International Forums General Discussion Hi Performance New 2 BBL intake on the horizon!

After many requests to produce one for these engines, here is the first rendering of the prototype. It will use the Rochester style 2G carbs. From here the patternmaking begins.

Ohhhhhhhh ahhhhhhhhh

That drawing bears a close resemblance to the stock manifold for my military GMC 302!

Yours, i daresay, will not be cast iron.

God's Peace to you.

d
Inliner #1450

Yeah Don, it will be aluminum. It fits the 194-292 engines and is also similar to the stock 250/292 1BBL intake in a lot of areas, then topped off with a 2 BBL carb flange. Many guys want to upgrade above the stock I BBL but don't want to jump all the way to a 4 BBL intake either. So this should fill the void and provide what they are looking for.

You may want to figure a way to use a standard 2300 Holley bolt pattern or one of the small progressive webers on it.

I think the Weber and the Rochester have the same bolt pattern. The 2300 baseplate is almost twice the size of the flange shown above, and the throttle bores are a lot larger also and would make the interchange more to deal with. It would be easier to just change the top pattern and cast a specific intake for the 2300 carbs.

I'm sure looking forward to this!

Or use an adapter plate for the already plentiful 4bbl manifolds.

Looks good. My 270 ran really strong with a GM 2bbl.

My real target group for this is the guy that wants to upgrade in a small way perhaps with a HEI conversion and maybe some good exhaust but still want to use his vehicle for towing and light duty hauling and still retain that off-idle grunt without sacrificing that. Also the smaller 194 and 230 guys have virtually no specific items for their cars that aren't more geared toward the bigger 250 and 292 engines.

Good idea.

Thanks, im dangerous when I have some spare time!

Whether you think so or not with a little time (well maybe more than a little) a 194-292 manifold will work on a 228-302 GMC. Did my first one 15 years ago and it's still woking just fine. I definately like the this one and can immagine it with 2 more Rochester bases............JD

Excellent!
I used to cast stuff back in school, based on that I'd say the casting would be even easier with 3 downspouts (eg 1 for each of 3 possible carb pads.....)
Since these freeze last, it would be easier with 3 spouts to change carb pad types (eg Roch 1v vs 2gc pads) without having casting troubles.

Also, what about water cooling?
I hate exhaust cooling as it corrodes/erodes alum intakes.

And, I would add some "bosses" for bolting carb linkage, maybe the original bosses on the side for using the stock linkage and powerglide stuff, etc, and on the top where the later 292 throttle cable mounts. It's tough when you have no bosses in the intake cuz the head/block are pretty sparse too, no place to solid mount anything. It kinda helps to think out any thick bosses first cuz you can have shrinkage/coldshuts (lack of metal fill) in those heavy areas and may need chills there in the design.

Should be relatively easy to offer a 1*2v, 3*2v, and 3*1v intake this way!

You read my mind jimmysix, I am looking at making an intake or two for the Jimmys also, since there hasn't been any made for them in 50 or 60 years. Adding a few carbs to this one and making it 3 x 2, or a 3 x 1 or other combos is also something I was going to incorporate and offer. So literally with just a few changes I can have 3 or 4 different intakes available. And yes, more bosses for linkage and water heating are going to be part of the design as well. I also have several other engines I am currently making models of right now and will plan on making them part of my my new line of production products. I literally have dozens of new intakes, side covers, valve covers, timing covers and a few cylinder heads for different engines that I have been developing over the past few months and with some new 3D CAD/CAM software I recently purchased, its going to be an interesting upcoming year for Inlines of all types. I've recently demonstrated on another forum with this software how easily I can go from concept to part in hand in just a few days with a variety of products. Any part is within reach now from blocks, heads, intakes...anything. The only limitation is the imagination!

Cool!

May I make a couple suggestions? The two outermost corners should probably have a larger radius. As shown the cross sectional area varies from small to large them small again around the outer corners. Or to think of it another way, there is a dead spot/turbulence in those corners. Also, most engines are mounted with a few degrees tilted rearward. As shown, your carb mounting flange or runner shapes do not account for this tilt. Further, stock manifolds flare out at the head flange to go around the head bolt bosses. Perhaps you don't intend to mate to stock heads, I don't know.

Not trying to shoot you down, I appreciate inititative. Just trying to be helpful.

The runner radius' on the end runners are the same as the stock intake manifold are on the outside of it, but on the inside they are much different than one might think they are just from the outward appearance and are smoothed out straighter. Thats one of those hidden features i've made into it that you cant see externally. The port flanges are just attached to represent the feature and not the actual flanges that will be cast on them. And yes, an angle of some amount will be compensated for in the carb mounting surface.

Also, for those that might not need the intake for your particular application, there is always the T-Shirt.

But the T-Shirt is white advertisers of automotive parts forget we are dirt and grease magnets.

You buy my black shop aprons for when your going to get greasy, T-shirts are for car shows or when you want some that looks cool to wear.

I'd add enough material to allow a GM TBI to bolt on. I'm really considering making up a kit that would have the ECM and harness & sensor included. The rest is available in the junkyard for not much $$$.

Do you have a dimension for the throttle bore size and spacing and bolt pattern. English instead of metric preferred.

Got the apron, but what about the parts and food that gets between the apron and the shirt?, cars shows and swap meets have soda, coffee and burgers, and margeritas all of which provide a colorful pallet for shirt decorations.

CNC-Dude, Have you considered a 4BBL with closer to equal length runners?

Actually I am drawing one right now, might have it ready to post a drawing of like the 2 BBL intake later tonight. I actually have 4 different intake manifolds for the 194-292 I am currently designing and fixing to start patternmaking for them immediately so I can begin casting them. Thanks for your interest.

Here's my new version of an "equal" length runner 4 BBL intake manifold. Its meant to be a race only style intake, but the center runner length is approx an inch longer than other conventional 4BBL intakes available currently.

I sold my last TBI so nothing to measure.

4.3L, 5.0L, and 5.7L GM engines have throttle body bores of 1 11/16" with approximately 2 7/16" (scaled from a photo) between bore centers.

http://www.dynamicefi.com/TBI_Fueling.php

Thanks Winter, i'll check it out.

That's still not a equal length runner. At least not in my eyes
from base of carb to the Port on the head. Your center runner is still closer (shorter) to the carb then the end two ports. And with it being a single plane intake. Like Yours, cliffords, and the Offey. Clyde was close but not vary friendly in much of any manner. Esp. street wise or Hood clearance. But his wasn't meant for the street to start with. I have seen ONE intake and the mold (cast) that had Equal length runners. And is one fine piece of work. But the guy has NO interest in selling it Or the patterns to it.:(
But either way I agree with most Your 2b intake should more carb mount friendly.(more then one bolt pattern)

Your right Larry, it's not exactly an equal runner design, but as I mentioned, the center runner is an inch longer than the other options(Offy, Clifford)which makes it a little more equal than those. Having said that, the "unequal" runner design of the Clifford and Offy still isn't bad either. Short of making a Log Style intake, it might not be something that can be done, and whether that type of intake is any better than what we have now is debatable im sure.
The more I think about it also Larry, I think your also correct as to allowing more options on the 2 BBL intake carb flange for different bolt patterns.

I think having all runners of equal length is way over rated. At least on a street engine.

Did the Mopar slant six have close to equal length intake runners? Or semi/close to equal length?

The factory 4 bbl slant six intake, never seen one that I remember about, were those equal length?

Forgot what those 4 bbl packaged cars were called? Anyone? 1964 or there abouts?

MBHD

Yeah they were called the Hyper Pak. Aussiespeed makes a similar long runner intake for them and they are pretty close to equal length. There was a guy over on the Slant6 forum, Doug Dutra, that reproduced the factory Hyper Pak version intake for a while, then Jack Clifford bought the patterns and they offer it as "Fat Pak" intake from time to time, when ever they feel like making some. I had one of the first 10 intakes that Doug cast and sold it for big bucks on eBay. Runners are 16 inches long. From all the racers that have tried to use it on the Slant forum, they say the standard Clifford intake makes more power.

The rare slant 6 factory intake is a dual 4, Tex Smith had one on the XR27 roadster for a while and I've seen one other on EBay with carbs and linkage where it sold for around $3500.00

They definately are wicked looking! You just don't expect to see something like that on a Slant 6 when you pop the hood. Of the 65-70 intakes that Doug Dutra cast, I think only about 10 have actually been bolted on to engines and had gas run through them, these guys just buy them mostly because they have become such a cult symbol to the Slant crowd. I kept mine long enough to make a set of patterns for one to start making them myself.

Hey Scott
one more thing food for thought. As I know with the offey there is not enough meat/spacing with the carb plate for most 4b linkage to clear the intake, with out using a spacer. Have you thought about that? Just thinking maybe? or could have the same issue with a 2b.

Larry I have thought of raising the carb pad up about 3/4" on an inch above the flat part of the plenum, thats how high it is in the drawing for the 2 BBL intake. I think the standard carb adapter plate thickness for the Clifford 4 BBL is only 1/2" thick, so I should be high enough compared to that way of thinking. Would you think I might need to make the flange a little taller then or is 3/4" a safe target to shoot for. I will also add some bosses for linkage to bolt to also.

CNC-Dude, Before there was a choice of intakes we would make 2" and 4" spacers to go between manifold and head. The 4" showed the most benefit with the Offy 3x1 setup.

I would like to see someone make a 4BBL manifold with the center runner coming into the plenum from the bottom as far as possible to the outer side. The end runners entering from the sides. This would require a raised plenum. That would mean more cores I know. This would more than likely be a race only part.
Just my thoughts.

The PES intake actually is designed the way you are describing, with the center runner entering the plenum area from the bottom side and is raised real high. Have you seen this intake manifold?

I notice the area underneath the carb has sharp 90 degree turns.
Would be good to has big radius' for each runner.
Just a thought.
I know when I tried to make nice radius' I broke through the upper part of the runner, near carb base & had to add welded aluminum.

MBHD