Better Stock Manifolds for '83 K20 4x4? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

MARKDTN · 05-10-2012, 07:25 AM

I have an '83 K20 that my uncle bought new. I drove it to 150k miles and then a cam lobe went down. I put a complete '91 L98 Tuned Port engine from a Corvette in. Motor is completely stock. I went from 14 mpg to 17, but now I have to run premium fuel. Anyway, I put back the stock exhaust manifolds. I have 2" true dual exhaust with Walker high flow cats and no mufflers. I think the stock log manifolds are restricting my flow. I have a set of Vortec manifolds from a '98 truck. I also have the manifolds from the '91 Corvette and a set of '94 LT1 Corvette manifolds. I have done a few searches, but can't find a good answer. What is the hot tip on cast iron manifolds that will fit a 4x4 3/4 ton in a 73-87? Preferrably ones that I can buy a stock headpipe for, but that is not a deal killer. I do not want headers. Thanks!

MARKDTN · 05-10-2012, 04:07 PM

No suggestions? How about this, are there any 4x4 applications that use other than the log manifolds? I have worked on a bunch of 2wd '70s trucks that all had a much more free-flowing style manifold (like in this post http://67-72chevytrucks.com/vboard/s...d.php?t=523628), but I don't know if they fit with a transfer case or not. I am worried, mostly on the passenger side how the pipe would route. I have not worked on a 4x4 that didn't have the log manifolds.

beamn7 · 05-10-2012, 05:00 PM

Well, I know my grandfathers 79 K20 / 400cu didn't have the log style manifolds. It had the ones like in the post you mentioned.
Looks like you could run a 14050282 on the right hand side (pass side) and 14067365 on the left hand side (driver side). Google image those numbers with manifold after the number for a pic. Walker makes pre-bent Y pipes if you wanted to go that route as well....

RockAuto lists these parts for a 82 K20. 83 shows them with the logs....

Hope this helps.

MARKDTN · 05-11-2012, 07:23 AM

Thanks! I will look into those.

motornut · 05-11-2012, 09:40 AM

I looked into stock for the 79 4X2 Jimmy
was told the walker stock duals for the 4X4 will hit the 4X2 crossmember
but it works on the 4X4 for duals

this grinding may help some flow too
I've gotten more "loud n rumble" with no "bumps"

motornut · 05-11-2012, 09:57 AM

http://www.summitracing.com/parts/WLK-89007/
but check here too

05-10-2012, 07:25 AM	#1
MARKDTN Registered User Join Date: Jan 2011 Location: Chattanooga, TN Posts: 2,165	Better Stock Manifolds for '83 K20 4x4? I have an '83 K20 that my uncle bought new. I drove it to 150k miles and then a cam lobe went down. I put a complete '91 L98 Tuned Port engine from a Corvette in. Motor is completely stock. I went from 14 mpg to 17, but now I have to run premium fuel. Anyway, I put back the stock exhaust manifolds. I have 2" true dual exhaust with Walker high flow cats and no mufflers. I think the stock log manifolds are restricting my flow. I have a set of Vortec manifolds from a '98 truck. I also have the manifolds from the '91 Corvette and a set of '94 LT1 Corvette manifolds. I have done a few searches, but can't find a good answer. What is the hot tip on cast iron manifolds that will fit a 4x4 3/4 ton in a 73-87? Preferrably ones that I can buy a stock headpipe for, but that is not a deal killer. I do not want headers. Thanks! __________________ '83 K20-TPI '73 C10 '79 C10-ex-diesel(SOLD) '07 Tahoe(Son driving) '14 Suburban-DD '71 C10-current project

05-10-2012, 04:07 PM	#2
MARKDTN Registered User Join Date: Jan 2011 Location: Chattanooga, TN Posts: 2,165	Re: Better Stock Manifolds for '83 K20 4x4? No suggestions? How about this, are there any 4x4 applications that use other than the log manifolds? I have worked on a bunch of 2wd '70s trucks that all had a much more free-flowing style manifold (like in this post http://67-72chevytrucks.com/vboard/s...d.php?t=523628), but I don't know if they fit with a transfer case or not. I am worried, mostly on the passenger side how the pipe would route. I have not worked on a 4x4 that didn't have the log manifolds. __________________ '83 K20-TPI '73 C10 '79 C10-ex-diesel(SOLD) '07 Tahoe(Son driving) '14 Suburban-DD '71 C10-current project

05-10-2012, 05:00 PM	#3
beamn7 Registered User Join Date: Oct 2011 Location: Wildomar, CA Posts: 466	Re: Better Stock Manifolds for '83 K20 4x4? Well, I know my grandfathers 79 K20 / 400cu didn't have the log style manifolds. It had the ones like in the post you mentioned. Looks like you could run a 14050282 on the right hand side (pass side) and 14067365 on the left hand side (driver side). Google image those numbers with manifold after the number for a pic. Walker makes pre-bent Y pipes if you wanted to go that route as well.... RockAuto lists these parts for a 82 K20. 83 shows them with the logs.... Hope this helps.

05-11-2012, 07:23 AM	#4
MARKDTN Registered User Join Date: Jan 2011 Location: Chattanooga, TN Posts: 2,165	Re: Better Stock Manifolds for '83 K20 4x4? Thanks! I will look into those. __________________ '83 K20-TPI '73 C10 '79 C10-ex-diesel(SOLD) '07 Tahoe(Son driving) '14 Suburban-DD '71 C10-current project

05-11-2012, 09:40 AM	#5
motornut 78K & 79C Jimmys Join Date: Nov 2009 Location: Ottawa Ont CANADA Posts: 7,901	Re: Better Stock Manifolds for '83 K20 4x4? I looked into stock for the 79 4X2 Jimmy was told the walker stock duals for the 4X4 will hit the 4X2 crossmember but it works on the 4X4 for duals this grinding may help some flow too I've gotten more "loud n rumble" with no "bumps" Attached Images __________________ John 1978 GMCJimmy4X4-350/203 1979 GMCJimmy4X2-305/350

05-11-2012, 09:57 AM	#6
motornut 78K & 79C Jimmys Join Date: Nov 2009 Location: Ottawa Ont CANADA Posts: 7,901	Re: Better Stock Manifolds for '83 K20 4x4? http://www.summitracing.com/parts/WLK-89007/ but check here too Attached Images __________________ John 1978 GMCJimmy4X4-350/203 1979 GMCJimmy4X2-305/350



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