Questions Regarding Siamesed Intake Ports (9 Port Head)

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moregrip
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Re: Questions Regarding Siamesed Intake Ports (9 Port Head)

Post by moregrip »

enigma57 wrote: Sun Feb 16, 2020 4:00 pm
moregrip wrote: Sun Feb 16, 2020 10:11 am......Question, if you had the room, would you be going the DCOE route?
That would be the most logical choice, given available manifolds...... Or Dellorto DLHAs. I like doing things differently, though. So I would look into sliding valve carburretors...... SU, Mikuni HSR. Something along those lines. :D

Best regards,

Harry
So my 250 inline is going in an 83 chevy C10; similar to your project (ok a bit newer). I'm thinking your truck might be a bit narrower in the engine bay? Many years ago I had a 59 Apache (never should of sold it) trying to picture in my head what the clearance might have been. Wondering if I might have room for the DCOE's. Anyway, just spit-balling. I'll start with the single 38 DGAS and go from there, KISS approach. Lot's of learning to do on my end!

What are your plans for a harmonic balancer? I read the larger SBC dampener works well on the 292. Love the work you've done on your intake manifolds, impressive for sure!
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Re: Questions Regarding Siamesed Intake Ports (9 Port Head)

Post by enigma57 »

:D My engine bay is even tighter than your '59 Apache was, moregrip. I am swapping the 292 into a '57 Chevy passenger car. This will be a road car. A driver. And I will pull a boat trailer with it up in the Texas hill country from time to time. I will use it like a truck. That's why I'm building the mechanicals like a truck.

With the 292 and any intake that extends outward very far at all, there are interference points with steering column, brake master cylinder and possibly the firewall at one place. The cast split exhaust manifolds I have here drop right into OEM mechanical clutch linkage, so will adapt Jeep hydraulic clutch master and slave cylinder to work the clutch.

I have a new GM 8" malleable iron torsional dampner (harm. balancer) for small block here. I may use it. I would welcome getting the drive belts off the balancer ring. 1/4" must be removed to make it work on the inline 6. Either from the balancer snout or by cutting a clearance notch in face of the crank gear. I'm considering splitting the difference and taking 1/8" off of both.

The main issue with going to a V-8 balancer will be whether the added overall engine length is workable in my engine compartment. Or stated another way...... Can I move the radiator far enough forward to pull it off?

I'm going to see if I can attach a file with some photos of the old girl. My apologies if they do not come through. I'm old and computers are a mystery to me.

Image

Happy Motoring,

Harry
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moregrip
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Re: Questions Regarding Siamesed Intake Ports (9 Port Head)

Post by moregrip »

enigma57 wrote: Sun Feb 16, 2020 7:57 pm :D My engine bay is even tighter than your '59 Apache was, moregrip. I am swapping the 292 into a '57 Chevy passenger car. This will be a road car. A driver. And I will pull a boat trailer with it up in the Texas hill country from time to time. I will use it like a truck. That's why I'm building the mechanicals like a truck.

With the 292 and any intake that extends outward very far at all, there are interference points with steering column, brake master cylinder and possibly the firewall at one place. The cast split exhaust manifolds I have here drop right into OEM mechanical clutch linkage, so will adapt Jeep hydraulic clutch master and slave cylinder to work the clutch.

I have a new GM 8" malleable iron torsional dampner (harm. balancer) for small block here. I may use it. I would welcome getting the drive belts off the balancer ring. 1/4" must be removed to make it work on the inline 6. Either from the balancer snout or by cutting a clearance notch in face of the crank gear. I'm considering splitting the difference and taking 1/8" off of both.

The main issue with going to a V-8 balancer will be whether the added overall engine length is workable in my engine compartment. Or stated another way...... Can I move the radiator far enough forward to pull it off?

I'm going to see if I can attach a file with some photos of the old girl. My apologies if they do not come through. I'm old and computers are a mystery to me.

Image

Happy Motoring,

Harry
Clearly I didn't catch on! lol, my apologies! but your 57 is a beaut! All makes sense now!
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Re: Questions Regarding Siamesed Intake Ports (9 Port Head)

Post by chevyfreak »

moregrip wrote: Sun Feb 16, 2020 7:03 pm
So my 250 inline is going in an 83 chevy C10; similar to your project (ok a bit newer). I'm thinking your truck might be a bit narrower in the engine bay? Many years ago I had a 59 Apache (never should of sold it) trying to picture in my head what the clearance might have been. Wondering if I might have room for the DCOE's. Anyway, just spit-balling. I'll start with the single 38 DGAS and go from there, KISS approach. Lot's of learning to do on my end!

What are your plans for a harmonic balancer? I read the larger SBC dampener works well on the 292. Love the work you've done on your intake manifolds, impressive for sure!
Hi. 38dgas weber will work good. Plain and simple carbs.
On most 38 webers the 27mm venturi can be opened up to 29mm with a step drill and drill press. Just verify thickness on body. And then some blending.

For a stock to near stock motor the std balancer is good. The 292 unit is bigger in weight and grooves in various locations depending acc drives.
Yes sbc dampers fit but stands out way more fwd, i used a chevy v6 damper on my 153 and machined a double groove pulley from sbc in the center so it goes on from the back of damper so grooves can line up with other pulleys.

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Re: Questions Regarding Siamesed Intake Ports (9 Port Head)

Post by enigma57 »

I will be looking into how the pulley behind damper mod would work with my setup, chevyfreak. Pretty sure at this point that I will be running the large 8" malleable iron dampner I have here. Bought it in the early '80s from a Chevy dealer for an engine I was building, but never used it. The engine I was building had an 8" dampner with the early timing mark location and my front cover had the corresponding timing tab for it, so I reused it and hung on to the malleable iron dampner.

With the 292, I need the heft of the larger, heavier dampner. So I will look at pulley behind and pulley in front of dampner configurations and see how that works with my 8" dampner and whether doing so will save me any space front to rear.

----------------------------------------------------------------------------------------------------------------------------------------------------------------

No apologies necessary, moregrip! She's a model 210 4dr sedan. Workhorse of the fleet, you might say. Not as snazzy as a Bel Air convertible or 2dr sport coupe. But just as much fun to drive.

The old girl has been resting up on blocks in my little suburban car and a half garage for many years now. I keep her registered here in Texas as an antique car in case I need to move her whilst getting her roadworthy again, but she still wears her '76 Saskatchewan plate on the rear and her tube type bias ply tires on close inspection are starting to look a bit dry rotted. Will definitely run radials when she's ready for the road.

Clifford still makes a dual carb intake. Not listed separately on their website, but available. And unlike the earlier Clifford castings, they have a heated plenum floor now. Just plumb engine coolant through it and back to the heater core. They also have adapter plates to run either Weber DGV or DGAS carbs. If that is what you would prefer to run, contact Larry at Clifford and he can set you up.

https://cliffordperformance.net/6-8-catalog

Like all Webers, these carbs require between 3 and 3.5 PSI max fuel pressure, so a fuel pressure regulator is required. Most OEM mechanical fuel pumps put out out twice that pressure. In the old days, we would put shims under the fuel pump to space it away from the block until we got the pressure down where it wouldn't overcome the needle and seat on these carbs. But this also reduces fuel volume and an adjustable fuel pressure regulator and gauge are really better. Takes no experimentation. Just set it for 3.5 PSI and you are done.

Do you rebuild carburettors? I have some matched 38 DGAS carbs here. Free to a good home if you want them. Just cover shipping and they are yours.

Happy Motoring,

Harry
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Re: Questions Regarding Siamesed Intake Ports (9 Port Head)

Post by moregrip »

enigma57 wrote: Mon Feb 17, 2020 5:41 am I will be looking into how the pulley behind damper mod would work with my setup, chevyfreak. Pretty sure at this point that I will be running the large 8" malleable iron dampner I have here. Bought it in the early '80s from a Chevy dealer for an engine I was building, but never used it. The engine I was building had an 8" dampner with the early timing mark location and my front cover had the corresponding timing tab for it, so I reused it and hung on to the malleable iron dampner.

With the 292, I need the heft of the larger, heavier dampner. So I will look at pulley behind and pulley in front of dampner configurations and see how that works with my 8" dampner and whether doing so will save me any space front to rear.

----------------------------------------------------------------------------------------------------------------------------------------------------------------

No apologies necessary, moregrip! She's a model 210 4dr sedan. Workhorse of the fleet, you might say. Not as snazzy as a Bel Air convertible or 2dr sport coupe. But just as much fun to drive.

The old girl has been resting up on blocks in my little suburban car and a half garage for many years now. I keep her registered here in Texas as an antique car in case I need to move her whilst getting her roadworthy again, but she still wears her '76 Saskatchewan plate on the rear and her tube type bias ply tires on close inspection are starting to look a bit dry rotted. Will definitely run radials when she's ready for the road.

Clifford still makes a dual carb intake. Not listed separately on their website, but available. And unlike the earlier Clifford castings, they have a heated plenum floor now. Just plumb engine coolant through it and back to the heater core. They also have adapter plates to run either Weber DGV or DGAS carbs. If that is what you would prefer to run, contact Larry at Clifford and he can set you up.

https://cliffordperformance.net/6-8-catalog

Like all Webers, these carbs require between 3 and 3.5 PSI max fuel pressure, so a fuel pressure regulator is required. Most OEM mechanical fuel pumps put out out twice that pressure. In the old days, we would put shims under the fuel pump to space it away from the block until we got the pressure down where it wouldn't overcome the needle and seat on these carbs. But this also reduces fuel volume and an adjustable fuel pressure regulator and gauge are really better. Takes no experimentation. Just set it for 3.5 PSI and you are done.

Do you rebuild carburettors? I have some matched 38 DGAS carbs here. Free to a good home if you want them. Just cover shipping and they are yours.

Happy Motoring,

Harry
Harry, wow, first off; very kind of you to offer! With that said, I haven't rebuilt a carburetor since my teens! Autoshop or the Texaco; can't remember. I wouldn't mind trying again though; be a fun project x2! I can PM you my info if you'd like.

I believe Coker still sells bias ply tires, maybe worth a look, otherwise, as I'm sure you're well aware, I've seen some radials that look nearly period correct.
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Re: Questions Regarding Siamesed Intake Ports (9 Port Head)

Post by pdq67 »

Back in HS, I wrecked a great '55 Bel Air 2-Dr HT screwing around. Wished I had it back as one of my '52 Willys Aero Eagle HT cars.

The '55 cost all of $350 back then and was in great shape. The Willys was given to me from my F-I-L, but I bought one earlier for $18.

My Buddy Tom blew everything from the back of his cammed 375hp/327FI engine and the front of his 4-speed!

I figure it let loose above 8,000 rpm AND he ran the sucker that way, He was paralyzed from the waist down so had hand controls in his '58 'Vette rag-top. Gene was shifting for him at the time.

Gene later said it sounded like a grenade going off under the car!

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Re: Questions Regarding Siamesed Intake Ports (9 Port Head)

Post by enigma57 »

Yeah, grenading a flywheel is no fun at all, Paul. Not a thing I care to repeat. Regarding shifting for others...... When we were in Jr. High (we were 12 yrs. old), we used to, errr...... 'Borrow' a friend's Step-dad's work car when he would leave it at home and ride to work with a buddy. It was a '51 Ford flathead. My friend had 1st dibs driving because it was his Step-dad's car. But he didn't know how to shift gears. And he was short. Very short. We had to stack a Geography book and a History book in the seat so he could 'just' see over the dashboard through the steering wheel. So I would ride shotgun and shift the gears (column shift) with my left hand.

When it was time to shift gears or to stop at a light, I would yell 'Clutch!' and he would push the clutch pedal down. Which was a challenge for him because he was so short. Of course cars had no seat belts in those days. Once, he had to stop quickly and slid off the seat onto the floor and I had to steer till he got back up in the seat again. I remember making a hard right turn wound out in 2nd gear through a corner gas station about 45 MPH and barely missed taking out a gas pump in order not to rearend the cars stopped at the light ahead as he struggled to get back up on the seat again. But we made it work. Eventually, I would get my turn to drive and off we'd go.

That was before my folks moved us up to the Texas hill country. In those days, we lived along Little Vince Bayou which flowed through Pasadena into the Houston Ship Channel. We would drive the '51 Ford across the railroad tracks to Sterling Street in Pasadena and turn right on the 2-lane blacktop road that paralleled the tracks from Pasadena through Deer Park and on to the refineries and chemical plants on the South side of the Ship Channel from Channelview.

There is a freeway there now. The 225 Freeway. But in those days, it was just a 2-lane blacktop road with bar ditches on both sides paralleling the railroad tracks. We would drive the Ford down that road about 70 MPH and turn left onto Battleground Road, which led to the San Jacinto Battlefield where Sam Houston caught up to Santa Anna and defeated his army in April of 1836. We'd drive up Battleground Road and see the Monument and then over to where the Battleship Texas is anchored. In those days, only the main roads there were blacktopped. The rest were crushed shell (oyster shell) or dirt tracks that were oiled down to cut the dust from time to time.

Lots of fun sliding around corners broadside and occasionally off the road and through the high grass. We always refilled the gas tank when we brought the Ford back, but my friend's Step-dad would give us a knowing look when he came home from work and the Ford's hood was warm to the touch and there were grass blades sticking out from between the rims and tube type tires where we slid off the road.

One time out on Battleground Road, I attempted a sharp right hand turn from the blacktop onto a crushed shell side road way too fast. Of course being 12 years old, I had no concept of what we could or could not make the Ford do. So at 75 MPH, I cut the wheel right and we slid sideways across a shallow bar ditch and spun out in the tall grass of a clearing beyond.

I managed to miss the guy trimming the hedge about 30 ft. away and keep the car from rolling. But we spun around 3 full revolutions out in the tall grass after going through the hedge and hooking a good sized chunk of it with the rear bumper where it wrapped around the fender at the right rear. That was problematic, as there was a bee nest in the hedge and every time we got near it to pull it off the car, the bees would fly at us. Driving 90 MPH didn't get rid of the hedge nor the bee hive either. So when we got back to Pasadena, we managed to play cowboy and lasso the hedge with a piece of rope. Tied the other end off to a fire hydrant and took off in the Ford, leaving the hedge and bees and rope behind.

Best regards,

Harry
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Re: Questions Regarding Siamesed Intake Ports (9 Port Head)

Post by enigma57 »

moregrip wrote: Mon Feb 17, 2020 1:39 pmHarry, wow, first off; very kind of you to offer! With that said, I haven't rebuilt a carburetor since my teens! Autoshop or the Texaco; can't remember. I wouldn't mind trying again though; be a fun project x2! I can PM you my info if you'd like.

I believe Coker still sells bias ply tires, maybe worth a look, otherwise, as I'm sure you're well aware, I've seen some radials that look nearly period correct.
:D Hi, moregrip! Yes, you are most welcome to the DGAS carbs if you'd like to freshen a couple of them up and run them on your inline 6 with a Clifford intake. These are matched Weber 38 DGAS carbs original to 1970s UK spec Essex V6 engines. Made in Italy. They have the correct 27mm fixed chokes and jetting to work very well as dual carbs on your engine. Being production carbs, I doubt that any of the jetting has been changed but you will be able to read the jet sizes when you pull them apart. If you must run 10% ethanol, you may need to bump idle (slow running) and main jets up a step but they should be pretty close as they are.

If you decide to go that way, I'll ship you a box of them a friend sent me from the UK some years back. You can have them for whatever it costs to ship them, as I will not be using them. These are production carbs made in Italy and original to UK spec Essex V-6 single carb engines. There are 4 carbs in the box. All need to be rebuilt. 2 of them are in good condition and should clean up nicely. The other 2 are good for spare parts and you can pull one of them apart to familiarize yourself with how they are made before freshening the 2 you will use on your 250 engine.

You can also use a piece or 2 from the parts carbs to test in whatever carb cleaning solution you plan to soak the builder carbs in to test it and make sure it won't harm the carbs. I used to use Varsol, but it seems to be hard to find here now of days. I did find a product at Lowes labeled Varsol, but it was sold as paint thinner and did not have the smell I recall 'real' Varsol having.

So for the last carb rebuild I did, I went to Lowes and picked up some gallon cans of regular old WD-40. Works better for hand cleaner than most of the stuff sold for that purpose now of days. I've used it for handcleaner the past 25 years or so.

WD-40 also makes (or at one time made) a cleaner/degreaser. I stumbled across mention of it a few years back on a forum where carb rebuilding was the topic. It was said to clean well without damaging carb bodies soaked overnight, but would take the plating off steel parts such as carb linkage pieces and throttle arms. I picked up a couple gallon cans but have not tried it on carbs as yet. Regular WD-40 was all I needed when cleaning up the last set of carbs I rebuilt. I let them soak in a covered container a week before beginning to loosen everything up (dirt and grease and fuel residue). So haven't tried the cleaner/degreaser I have here as yet. Figure I'll save it for cleaning small parts when rebuilding the 292 engine, the T-85N transmission or the rearend.

I was going to give you a link to this WD-40 degreaser product in case you might want to try it, but I don't see it listed in WD40's product page any more. Just some water based cleaner/degreaser and a solvent based cleaner / degreaser, neither of which seem to be what I bought in the 1 gallon cans.

I did see these spray on products though (might work for cleaning carbs either before......

https://www.wd40.com/products/industria ... degreaser/

Or following soaking them either in solvent or regular WD-40......

https://www.wd40.com/products/carb-thro ... s-cleaner/

Here's a pretty good introduction to the Weber DGV (progressive opening) and DGAS (synchronous opening) carburettors......



Exploded view......

http://www.lcengineering.com/LCTechPages/pdf/38DGAS.pdf

And some tuning notes......

http://www.redlineweber.com/html/Tech/3 ... unning.htm

https://www.racetep.com/manufacturer/ca ... carbs.html

https://www.racetep.com/manufacturer/ca ... pumps.html

I realize the exploded view showing each individual part makes disassembly and reassembly look complicated. But it really isn't. And with any luck at all, there may be sub assemblies such as throttle shafts, throttle blades and the intersecting drive gears which synchronize throttle blade opening that you may find not to need complete disassembly from the carb body after thorough cleaning and degreasing, for instance.

Clifford have a dual 38 DGAS setup and Larry can set you up with a bare dual carb intake and 2 carb adapters to suit the DGAS carbs. Probably linkage parts and other items from their complete kits as well. I am assuming that Clifford use the newer Spanish built DGAS carbs unless they have a cache of NOS Italian built Weber carbs, as Weber production shifted from Italy to Spain around 1992.

The dual carb intake isn't listed separately on Clifford's website, but if you contact Larry personally, he can set you up with the intake and a couple of adapters to fit the DGAS carbs to it. That's what I did for the dual carb intake. Only I have to make my own adapter plates because I am running the DCNF / DCNVH carbs and they have a different mounting pattern from the DGV / DGAS carbs.

Here is a video of a Clifford dual carb setup with DGAS carbs on an older 235 Chevy engine. It will give you an idea of how the basic setup is put together and how the throttle linkage is configured. Yeah, the guy operating the starter switch drove me crazy, bless his heart. He must have gotten used to EFI. With carbs, you need to crack the throttle slightly and if the engine is a cold start, possibly pump the gas once or twice as well before turning it over to prime the carb (depending on engine and how tuned)......



I should mention that the box of carbs is fairly heavy, so with current shipping costs (I use USPS), shipping them may be expensive now of days. If you decide to go this route, PM me and let me know your shipping address and I will see what I can do. I'll leave you a PM with my E-mail address so we can work out the details.

No worries on bias ply tires. I will be running radials on the '57 when I have her going again. Blackwalls. Knees are shot and at my age, keeping wide whitewall tires looking good is not something I would look forward to. :wink:

Best regards,

Harry
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Re: Questions Regarding Siamesed Intake Ports (9 Port Head)

Post by pdq67 »

enigma57 wrote: Sun Feb 16, 2020 7:57 pm :D My engine bay is even tighter than your '59 Apache was, moregrip. I am swapping the 292 into a '57 Chevy passenger car. This will be a road car. A driver. And I will pull a boat trailer with it up in the Texas hill country from time to time. I will use it like a truck. That's why I'm building the mechanicals like a truck.

With the 292 and any intake that extends outward very far at all, there are interference points with steering column, brake master cylinder and possibly the firewall at one place. The cast split exhaust manifolds I have here drop right into OEM mechanical clutch linkage, so will adapt Jeep hydraulic clutch master and slave cylinder to work the clutch.

I have a new GM 8" malleable iron torsional dampner (harm. balancer) for small block here. I may use it. I would welcome getting the drive belts off the balancer ring. 1/4" must be removed to make it work on the inline 6. Either from the balancer snout or by cutting a clearance notch in face of the crank gear. I'm considering splitting the difference and taking 1/8" off of both.

The main issue with going to a V-8 balancer will be whether the added overall engine length is workable in my engine compartment. Or stated another way...... Can I move the radiator far enough forward to pull it off?

I'm going to see if I can attach a file with some photos of the old girl. My apologies if they do not come through. I'm old and computers are a mystery to me.

Image

Happy Motoring,

Harry
Harry,

I guess that I never realized the differences between the stove-bolt 6's and the newer ones and how much hassle it is to use a newer 6-banger in an older 6-banger car/truck.

pdq67
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Re: Questions Regarding Siamesed Intake Ports (9 Port Head)

Post by enigma57 »

:D Its not such a hard swap, Paul. The later model inline 6 uses same bellhousing as small block and big block V-8. So I will use a '55 - '57 Chevy V-8 passenger car bellhousing, 168 tooth V-8 flywheel and 3-bolt starter that bolts to the bellhousing. This will allow me to retain the stock '57 bellhousing mounts and position the rear of the 292 engine where it should be.

The front engine mounts will need to be done from scratch, though. For that, I have trial fitted a 292 block in the engine bay, bolted the '57 bellhousing and bellhousing mounts to it and have put wooden blocks under the front to position it where it should be. There are any number of ways to do the front mounts. I have decided to make some brackets and use '32 - '48 Ford flathead engine mount cushions. These are strong, well designed and cannot pull apart like many newer style bonded engine mounts, as they utilize a through bolt design. I used a modified Hurst front mount kit when I swapped a 400 Pontiac into my '56 Chevy in the '70s. These used the flathead Ford engine mount cushions and they worked very well......

Image

Here is a 292 in a '52 Chevy pickup with fabricated brackets using these cushions. My chassis is made differently, but this is one way of using these cushions......

Image

This is a '57 Chevy frame (not mine). Shows general layout.....

Image

Overall engine length will determine what I can or cannot do with respect to torsional dampners. The 292 engine is an inch or more longer than my 235 as it is. If I use a V-8 dampner with separate crank pulley, that will add even more to the overall length. And then it will all hinge on whether there is room to move the radiator forward enough to gain the needed space.

These are Langdon split exhaust manifolds. Same as I am using. Unfortunately, the stock '55 - '57 mechanical clutch linkage is right where these manifolds dump, so that has to go as well. Will adapt Jeep hydraulic clutch master and slave cylinders to work the Chevy clutch......

Image

Oil pan...... With the '57 passenger car, I'll need to rework the front of the 292 oil pan sump to clear my steering cross link.

Just the usual details.

Best regards,

Harry
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