headers vs manifolds

[GMCrazy]

I'm rebuilding my GMC's 327, and im debating on keeping manifolds or adding headers. ive built a 350 before and put headers on it, however, I had continuous gasket blowouts. I tried the "no blow" copper gaskets with no luck, and Ive heard several other complaints about headers. What do you guys think? Are the horsepower gains worth the extra heat and blown gaskets? I also want to keep the truck relatively quiet, but of course I want to squeeze out as many more horses as possible. Thanks, David

[70c10]

Everybody claims the aluminum dead soft gaskets are thicker and better. I'm buying a set this week for my collectors I can't get to seal. I would still prefer headers over manifold type though. Ceramic reduces heat!

[Ackattack]

I got jet hot coated dynomax headers from summit for a little over $200. I haven't ran into much problems with them and I think they're worth the gain.

[neonlarry]

Iv'e often wondered what a set of extrude honed corvette manifolds with their 2 1/2" outlets would dyno compared to a set of headers. I know Brzezinski Racing gets some pretty good H.P. figures out of engines with modified stock cast iron components. Iv'e seen figures on gains on their intakes but not exhaust.
Why not give it a try and let the rest of us know?

[cableguy0]

i dont care how much porting or whatever you do to a set of manifolds they cannot flow what a set of headers can there is a lot more area inside a header tube than inside a manifold

[Longhorn Man]

And I am one of the guys running the dead soft alluminum collector gaskets. I have had them on 2 sets of headers, and removed probably at least a dozen times in the last 3 years owning them.
If they don't seal on your headers, I'd probably buy them from you for recomending them and being wrong.

THAT is how much I like them...and every one knows how cheap I am..

[huggerk5]

I was running Hooker Super Comp w/ 3" collectors. The motor is 383 that dynod on water brake 466 lb ft trq @ 3000 rpm. I had to do a lot of trimming to and bending to get them in the truck. It didn't work to good. Seemed they were rubbing every where. Any way I replaced them withe 2 1/2" cast iron corvette manifolds. I can assure they do not leak. I noticed one day that a bolt had fallen out and they were still sealed as best as I can tell. Any way I can't physically tell the difference and I tollerate the lack of trouble alot better. I found my at junk yard and one had a broken ear on collector. I brazed it up and threaded it, but it failed about a year later. I was suprised to find the part new from Chevrolet and if I remember it wasn,t that costly.

[Longhorn Man]

Just for the record, the hookers fit like a dream in a 2 wheel drive truck.
I sat here looking at your post wondering why your hookers didn't fit. Took me a few moments before I looked at your screen name.

[1971 Cheyenne]

Longhornmail, What kind of hookers are you running?

[crazy longhorn]

Originally posted by longhornmail
Just for the record, the hookers fit like a dream in a 2 wheel drive truck.
I sat here looking at your post wondering why your hookers didn't fit. Took me a few moments before I looked at your screen name.

I had to think about that one for a while also! The K5 tells the story tho. I am running Hooker Comps on my longhorn, with the sb mounted in I 6 position......the fit was great (2452 on the # if memeory is with me). The comps have a smaller collector,(2 1/2, with 1 5/8" tubes). They are a little heavier than the super comps(16 guage tubing), but are not equal lenght headers. crazyL

[Longhorn Man]

Hooker Super Comps. I convinced the crazy guy above to get some too.

[GMCrazy]

thanks for the input, i will most likely run them also!

[lukecp]

As long as you re-check the tightness on your headerbolts after the initian startup with headers, and maybe every time you do an oil change, the gaskets won't leak. I am running standard Fel-Pro manifold gaskets in mine right now...and they seem to work pretty good. They are cheaper than actual header gaskets and easier to install.

[Cap'n Hook]

Ya'll need to invest in locking header bolts. For the $30-$40 spent, you'll appreciate not having to worry about retightening ever-other week. I had these on my '85 with a GM Performance parts HO 350 and headman headers. Never had a leak or had to retighten in the 1½ years I had the truck!!

[huggerk5]

Did not mean to confuse with my statment. The part of the story I did not tell was that I bought off a camaro bracket car that was converting to a big block. I was in the process of dynoing the motor and wanted to see what they would do. After the numbers I knew I had to make them fit. He is where the problem was camaro to the Blazer. I did make them work, but it was never right in fact when I would get on the brake with hubs locked in the front drive shaft would rub the right header not a good thing in fact I was chasing a coyote and knocked a whole in the header. Basically I destroyed a nice set of headers. A lesson learned only buy what was made for the vehicle. How ever i have zero problem with the cast iron manifolds and behind the wheel I can't tell any difference. I am running them through flow master 70's I think with an H pipe which quieted things tremendouslyand has a very nice sound. With the headers I had to turn the motor off at drive thrus to place an order.

[GMCrazy]

i agree with the noise problem, i had headers on a Ranger one time (heh) and they were loud as hell. im still not sure which im going to go with on the GMC, but ill definately let everyone know which one and how it turns out. thanks so much for all the great input!

[1971 Cheyenne]

Jeesh! Those super comps don't come at an easy price. about 350 for regular black ones. For the ceramic coated ones about 530. Sure are pretty tho. Any other ways to get a awesome finish on them without spending 200 bucks extra? Are you guys happy with the performance?

thanks,

Poodude

[GMCrazy]

$530.00!!! those manifolds are starting to look a little less restricting.

[Longhorn Man]

LOL I got lucky, mine were on the truck when i bought it. That is about the only thing the last owner did right.



The headers have never hit the ground. The front end won't go low enough...and that is with the soggy sagging 500,000mile old front springs. Also spark plugs come out easily with only one plug needing a wrench...a socket on all the rest. Plug clearance is a little tight though, I use BOSH upers, only becouse they are the shortest non-specialty plug out there...that and they are only 99 cents each.

[GMCrazy]

is there any paint for headers that will not eventually burn off? the last set i bought burnt the so called heat risistant paint off in a week. the ceramic coated would be great.... but i have to buy food once in a while too.

[CPNE]

I have a complete dual exhaust system including hooker headers, hpipe and flowmasters. It is for a LWB truck, still sitting in frame. From AZ so it's solid. The catch? It's all welded together, albiet a nice job.

I was going to use it but opted for the rams horns for the sake of simplicity (clutch linkage, changing plugs, burnt wires, etc.)

Sell for $50 complete, you remove and pick up.

[Longhorn Man]

I have never found a paint that holds up.
I had some that lasted a week, then turned brown and rinced off the next time i washed my engine...ceramic something or another.

[ABHaulR]

are those headers in a 2wd or a 4wd???

[GMCrazy]

jeff, if i didnt live so far away, i would come get the exhaust from you with CASH money ill bet you're considering delivery now...

i believe the headers we've been discussing are for 2x4, they may fit 4x4; andy can probably tell for sure

[Longhorn Man]

2 wheel drive is what I been talking about, and what I have pictured there.