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Old 01-19-2018, 03:53 PM   #1
VWNate1
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Thumbs up Re: Post Your Straight Six Pics!

Multiple countries separated by a 'common language' .

I hope we get some video with sound of this beast when it runs .
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Old 08-18-2020, 04:09 AM   #2
Randy S. Hager
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Re: Post Your Straight Six Pics!

REVIVAL...….yeah let see some more recent pictures of the chevy inline 6 engines. Here is one I pinched off a site called Mercado Livre (eBay of Latin America-Brazil) I'm getting my friend down there to buy me that kind of intake for my 250 and also that really nice valve cover.

Cheers
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Old 08-18-2020, 11:55 AM   #3
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Thumbs up Re: Post Your Straight Six Pics!

Thank you .
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Old 08-18-2020, 12:47 PM   #4
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Re: Post Your Straight Six Pics!

292 in process
+.040" Silv-O-Lite flat tops
Lump ported head
comp 280h single profile cam
4-Barrell intake & Holley 390cfm
Transmission??? TBD
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Old 08-18-2020, 06:31 PM   #5
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Re: Post Your Straight Six Pics!

Quote:
Originally Posted by Randy S. Hager View Post
REVIVAL...….yeah let see some more recent pictures of the chevy inline 6 engines. Here is one I pinched off a site called Mercado Livre (eBay of Latin America-Brazil) I'm getting my friend down there to buy me that kind of intake for my 250 and also that really nice valve cover.

Cheers
Randy
So that is NOT a Clifford intake?
Tom Lowe at www.12-bolt.com
Sometimes has those valve covers.
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Old 02-21-2022, 04:04 PM   #6
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Re: Post Your Straight Six Pics!

JAV6 --Sweet looking L6.
What carb is that?
I have the same Offy intake, with Clifford headers and an Edelbrock 1404 [500 CFM] 4 barrel. And HEI.
My 292 is also the original. I rebuilt a '67 block and ran that one for 25 years, before I rebuilt the OEM block. Back on the road in 2005.
Bottom pic is from build up.
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Old 02-21-2022, 04:14 PM   #7
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Re: Post Your Straight Six Pics!

This looks like a good way to go in my opinion, here is a few pictures of my 292. I turned my Holley 90 degrees so that it would face forward. I have the cast iron headers and using a 200-4R transmission.
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Old 02-21-2022, 04:25 PM   #8
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Re: Post Your Straight Six Pics!

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This looks like a good way to go in my opinion, here is a few pictures of my 292. I turned my Holley 90 degrees so that it would face forward.
I've had debates with guys over what orientation a 4 bbl carb should be on a modified L6. My personal opinion -- and I am no High Performance expert -- is that with the carb looking ''sidesaddle'' the primaries open up to the cylinders evenly. With a 90* pitch, 4-5-6 will get the full blast of opening secondaries first.
Experts tell me it doesn't matter.
If transmission linkage is an issue, I can see using that configuration. I cut the Ford kick-down parts off my Holley 390 -- I run the SM465 manual.
Very neat A/C set up, BTW.
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Old 02-22-2022, 10:13 AM   #9
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Re: Post Your Straight Six Pics!

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I've had debates with guys over what orientation a 4 bbl carb should be on a modified L6. My personal opinion -- and I am no High Performance expert -- is that with the carb looking ''sidesaddle'' the primaries open up to the cylinders evenly. With a 90* pitch, 4-5-6 will get the full blast of opening secondaries first.
Experts tell me it doesn't matter.
If transmission linkage is an issue, I can see using that configuration. I cut the Ford kick-down parts off my Holley 390 -- I run the SM465 manual.
Very neat A/C set up, BTW.
I understand your logic, but to me it was about the way I thought the carb should be facing. Also connecting the linkage for both throttle and transmission seemed easier to me. That being said it seems to perform just great even though I have only made a few short trips with it. One bad thing about it sitting this way is if you need to adjust the hight speed idle you have to pull the carb to adjust it, but once done everything's fine.
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Old 02-21-2022, 10:15 PM   #10
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Re: Post Your Straight Six Pics!

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Originally Posted by '68OrangeSunshine View Post
JAV6 --Sweet looking L6.
What carb is that?
I have the same Offy intake, with Clifford headers and an Edelbrock 1404 [500 CFM] 4 barrel. And HEI.
My 292 is also the original. I rebuilt a '67 block and ran that one for 25 years, before I rebuilt the OEM block. Back on the road in 2005.
Bottom pic is from build up.
68Orange,
Thank you, It's an Edelbrock 500CFM AVS2, I went along a similar route as you just oriented it towards the valve cover. I believe it set up the ideal location for the Lokar throttle cables towards the front. The AVS2 also allows me to use either side for a fuel inlet. With any luck it will run well.
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Old 02-21-2022, 10:43 PM   #11
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Re: Post Your Straight Six Pics!

Cool. I converted my '68 to a '72-style throttle cable too. My choke cable is forward, and the throttle lever is aft. That way the air/fuel mixture screws point to the drivers fender -- easy to work on.

The old bellcrank linkage to my old Holley 390 CFM was too clunky. It could bind, drop out parts, and once even froze up with rime ice at high RPM driving home in the mountains from a ski trip. I had to use the clutch rather judiciously and shut off the ignition when I got to a burger stand for a break. After half an hour at the warmer temps at the lower altitude, the carb-ice broke off.

I ran the Holley for 25 years until right after the 500-mile break-in on the current 292, and the Holley went out on a backfire. It would not let itself be set up again, even after a fresh power valve. Manifold leakage due to a warped carb base was suspected. Rather than repair a 25 year old carb with a new base plate, it was cheaper to get a new Edelbrock.

The Performer Series are clones of the old Carter AFB [Aluminum Four Barrel] carbs. The Thunderor Series are copies of the old Carter AVS [Aluminum Vacuum Secondary], except that the Carter AVS had three step metering rods and cupped jets. That allowed an intermediate power stage to be set up -- like for towing. Edelbrock changed out their AVS for a two stage Rod and Jet system, same as on the AFB.

I found an abused, discarded AVS carb among some movie props, and bought parts for it, but the secondary stage is only some small spray nozzles, not the annular rings found in most big carbs. I have not tried it. The numbers show it was for a Big Block Mopar, once. Maybe it came off one of the many studio-trashed General Lees? No one will ever know.
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Old 02-22-2022, 03:30 PM   #12
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Re: Post Your Straight Six Pics!

With my Edselbrock facing left, all I have to do to adjust air/fuel mixture and idle is lean over the driver's side fender. Just sayin'...
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Old 02-22-2022, 05:21 PM   #13
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Re: Post Your Straight Six Pics!

AVS actually stands for "Air Valve Secondary". I've had a Carter AVS on my 292 for about 18 years now.
My throttle cable loops around and over the valve cover. My original, but modified oil bath was even farther modified after this picture to contain a paper filter. I tried, but never could get it to stop leaking oil all over itself.

I looked at the 4bbl carb orientation from the viewpoint of intake manifold runner length. Generally long runner lengths are better for low rpm and short runners work better for high rpm engine power. An inline engine with a single center mount presents a mix of both and a slight imbalance. Inline engines with a single center mount tend to run lean in the end cylinders and richer in the center cylinders.

If you use a string or narrow tape measure to check the distance from the head flange to the carb primary valve it is very long for cyl 1,2 as well as cyl 5,6. Cyl 3,4 is very, very short, especially if both primaries are inboard.
On my Clifford, the inboard ports are only about 4" from the 3,4 head flange, but the outboard ports are 6". The forward primary port is 11" from the 1.2 flange and the rear primary port is the same 11" to the 5,6 flange.

6" vs 11" isn't ideal, but a lot better that 4" vs 11" if both primary throttles are inboard.
If the carb is turned 90* to the head, one primary is 4", the other 6" from the 3,4 flange. Two primaries are 10" from the 1.2 flange and 12" from the 5,6 flange.

Truth be told, it doesn't seem to make a bit of difference, especially from the seat of the pants of most drivers with that setup.
Personally, the thought of that intentional imbalance drives me crazy.

The real world advantage of the sideways carb is the original style throttle rod linkage.

You might think that at WOT, all ports are equal distance in any orientation, but most of these carbs have smaller primary bores. Only the Carter AVS used on the 440 had 1 11/16" x 1 11/16" pri/sec bore. The Ed 800cfm AVS2 has even larger 1.75" x 1.75" pri/sec. All the other AVS carbs use smaller primaries.
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Old 02-22-2022, 09:25 PM   #14
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Re: Post Your Straight Six Pics!

Richard J and 68Orange,

You both make great points on the carb orientation and there seems to be many ways to skin the cat. Interestingly enough the Offy instructions recommend to position the primaries inboard. Still a work in progress, had to go to a 7" K&N filter to clear the brake booster. Richard I like your air filter setup, I wish I could have kept mine but it just wouldn't work in the current config.
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Old 02-23-2022, 01:06 AM   #15
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Re: Post Your Straight Six Pics!

JAV 6 Cool rig.
Richard, you rock it Dude.
A/C, P/S, L-25 292.
No heater needed in SoCal?
JAV6
I have a paper filter, on a 12'' Morose sombrero, aftermarket air cleaner. When I ditched the Monojet years ago, I lost a lot of stock connections.
I have a K&N element for it, but I'm leary of K+N parts, as they are flammable in an engine fire. Also shy of plastic fuel filters, as they can melt and spray gas all over the engine bay if exposed to very high temps.
[Those are the names of the demons that took down my '67 K/10 Suburban, w/454. Learned it the hard way.]
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Old 02-23-2022, 12:51 PM   #16
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Re: Post Your Straight Six Pics!

I gained 4-5 inches of clearance around the carb by bolting the brake booster directly to the firewall and eliminating that brake rod bell crank linkage.

I think Offy may have suggested that orientation back in the '60s when they offered this bell crank setup that was supposed to connect to the original auto kick down rod and throttle rod.
Your Lokar cable didn't exist for another 20 years after this manifold was first introduced.
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Old 02-23-2022, 10:57 PM   #17
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Re: Post Your Straight Six Pics!

A lot of the bellcrank, boomerang parts came with the original Offenhauser intake kit.
I have no pix of the old set up. [Who thought anyone in the ''Future'' would ever be interested in what's under the hood].
Even before I tore down the doghouse on my Orange rig to pull the '67 block out, I rigged my Holley 8007 with a 50cc accelerator pump shot and a cable.
I used parts from a '72 GM truck and a non-Lokar cable.
Pic attached of the cable I have. [Shot of the glovebox spare cable]

I was ever so happy when I switched to cable. I could never get WOT out of that Rube Goldberg set up. I had to relearn how to use the gas pedal.
With cable I had instant response. Hair trigger. Had to keep foot off gas at a light. Wide open throttle was waiting my toe tip.
And no jams, breaks or lag.
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Old 02-24-2022, 08:51 PM   #18
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Re: Post Your Straight Six Pics!

Good points both. The bell crank method really looked like a bad idea from the get go.
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Old 03-30-2024, 11:24 AM   #19
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Re: Post Your Straight Six Pics!

Here is my 250 in my '69.
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Old 03-30-2024, 02:03 PM   #20
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Re: Post Your Straight Six Pics!

It’s a work in progress still. I haven’t decided yet if it’s going in my ‘67 c10 swb, or my ‘67 c50 (shortened big pickup project - still looking for an original orange long box fleetside in decent shape). Thanks to Tom Lowe at 12bolt.com for the unique performance parts.
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Old 03-30-2024, 04:05 PM   #21
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Re: Post Your Straight Six Pics!

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It’s a work in progress still. I haven’t decided yet if it’s going in my ‘67 c10 swb, or my ‘67 c50 (shortened big pickup project - still looking for an original orange long box fleetside in decent shape). Thanks to Tom Lowe at 12bolt.com for the unique performance parts.
That's a promising looking L25 [292's RPO]. Way cool valve cover. And I dig the pre-1967 Alpine Green. I have a MY '63 292 core that is that Green. I may rebuild it and put it in my '67 K/10 Suburban. And keep it green.

For my 2 cents, I would put the 292 in the '67 C/10 Shortbed. My '68 C/10 Stepside was originally optioned with the L25, and it rocks. I rebuilt my OEM '68 block in 2005 with HiPo options. I ran a '67 292 block from 1977 to 2002, for 250,000 miles until the rings were shot.

I would go with a bigger engine in the C/50. Especially if you're gonna tow with it.
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Old 03-30-2024, 03:54 PM   #22
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Re: Post Your Straight Six Pics!

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Here is my 250 in my '69.
Nice mill. I like the Chevrolet scripted Valve Cover.
Is that the Offy intake? If so, what carb are you running?

For safety reasons, I would replace the plastic fuel filter over the manifolds with a steel-can type.
I had a plastic fuel filter almost melt thru during an engine fire once.
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