Dejavet

I want to replace the stock exhaust manafold on the 327 350 in my 65. Can I get hedders that will match up to my stock side exhaust? I would like to maintain a close look to stock if possible, so do they make headers that look similar to the stock exhaust manafold? The car is a 4 speed with standard brakes and power steering.

Dennis Beck

I am using a Patriot H8019-1 header on my 66 with sidepipes. You will need a header that clears your steering box. I do have to cut and fab my sidepipes to meet the header however. I don't think you will find a header that will mate to a sidepipe without some fabricating. You will also lose the ability to hang your alternator etc.
http://www.solisearch.net/ims/pic.ph...4z4vYB&i=78557
http://www.solisearch.net/ims/pic.ph...4z4vYB&i=78559
http://www.solisearch.net/ims/pic.ph...4z4vYB&i=78551
http://www.solisearch.net/ims/pic.ph...4z4vYB&i=78552

67tripwr

This is what I am working on now! Heddman is the only company that makes these for side exhaust corvette! I am doing away with the hooker stuff and going with factory covers, Heddman Headers, side piped from sweet thunder!







You will need the small block version available from Summit! You will also need to have a muffler shop make the connection from collector to side exhaust. Dennis is correct, in regards to the connection.

http://store.summitracing.com/defaul...h.asp&x=56&y=8

This is gonna be fun

Ol Blue

When I bought my Heddman headers to fit factory side pipes they came with a flange and adapter tube that slipped inside the factory sidepipes. I clamped them and they have held for years but you could have them welded. It was a perfect fit, no fabrication required.
Ol Blue
http://www.knology.net/~corvettes/63vett.jpg

Hitch

Just to play devil's advocate... On your 65 with the stock 2.5 ramshorn manifolds I doubt you will see much difference in power.... Just burnt plug wires and higher underhood temps... Also is this a stock motor??? Dave....

Dejavet

Thanks to everyone for all the good information. In response to YOUWISH2BME, I am suprised at your comment about not much difference in power with headers. This is the original 327, 350, but I intend to bring it up to 400 or so with head work, cam, roller rockers, ect. I am trying to maintain the original look as much as possible and for that reason I really don't want to go to headers, but with the increase in power I expect I will need to imporve exhaust flow. I am also concerned about higher tempatures, so I though I would get ceramic coated headers or have them coated. If I do not go to headers I assume I will not get all the power I paid for. Anyone else have an opinon on this?

Veet 66

OL Blue. Do you remember the part number or where you bought them?

Hitch

Trust me the "OLD" stock 2.5" manifolds will flow plenty good... My car has a hot 327 in it and has no problems running mid 13 second passes in the 1/4.... Just port match the manifolds to the heads and that will improve the flow quite a bit... Dave..

Dejavet

Dave, Do you have any estimate of how many horses you are loosing by not using headers with your hot 327? As I said, I like the original look, but I don't want to leave too many horses on the table. I also don't want to have to figure out how to mount the alternator. I was hopeing someone would tell me that there was a high flow exhaust that looked original such as they have with the big blocks.

ZO6RON

I am using the headman headers om my 64 with a zz4 and keisler 5 speed, being the zz4 is a D port exhaust i had ED'S headers make me some 3/8 thick flanges then cut the 1/4 flanges off and formed the tubes to the D port shape and TIG welded them together. This is very time consumming but the only solution. also am using the sweet thunder 3' tubes.

Hitch

I really don't think that I'm leaving much on the table with the work I did on the manifolds to port match them and smooth out the interior casting flash.. I don't have a link or any hard evidence that I can point you to, however I spent some time talking to others here on the forum and thru local contacts.. Headers may make some difference but on street motors the effect is neglible... I guess it boils down to how much racer boy stuff you want to have on your car... Dave...

67tripwr

You will be hard pressed to convince me, or anyone else that their is no substantial benefit from the use of headers. That is right even on a street car!

One of the many great benefits, is the way headers scavenge spent fumes from each cylinder, better fuel economy, increased hp, better low end torque, weight reduction, lower underhood temps.

Many say, that factory manifolds suck! I don't think their that bad, but not as efficient as headers

For the street, this is one of the best buys around! For the price, it is still the best value for performance return for money spent!

65convt

I also have Heddman for the 65 BB Coupe we are building. Got them through Summit last year. Ceramic coated $319.00.
I had the same back in the early 70's on a 65 Fuelie convt. Wish I still had that one today

Biggus Blockus

Heddmans here also on my 65 BB. Painted them hi-temp cast iron grey.
Great header for the price.
4" sidepipes from Mike at www.Sweet-Thunder.com.

Killer set up. I have the best sounding midyear on the planet. (in all humility)

65-StingRay

I bought some Hedman Hedders for my 65 BB this year after years of using a set of hooker headers. The hooker headers had the collectors facing the rear of the car requiring two 90 degree mandrel bent pipes back toward the front of the sidepipe. The Hedman's bend directly toward the sidepipe. Purchased the Hedman's for $189.00 and will ceramic coat them later as well as Sweet Thunder's 2.5 inch sidepipes. Should be a breeze to mate them together.

And yes I think headers make a big difference compared to the stock manifolds especially if your adding extra ponies to the mix. When I changed from stock ex. man. to headers I noticed a definite difference in acceleration, fuel economy, and sound. The more horses I added over the years the better the performance and desire-abilityof the headers.
Wayne G.

STING67RAY

hope you don't mind my jumping in here.
a lotta talk about sweet thunder sidepipes. are they better flowing ?
what about the sound? is it the same as stock GM pipes, or louder?
looking for more flow but not the loudness. i take mine on long trips.
B.G. once or twice year. woodward dream cruise, e.t.c.
everyones advice is always appreciated.

65convt

I don't know what your idea of LOUD is.
I do know that long cruises with a 411 gear and side exhaust will tend to deafen you some. But theres nothing that sounds like a BB with side exhaust.
People WILL know that your coming

JohnZ

Headers provide virtually no scavenging effect at all with a stock exhaust system or a system with similar restriction; they're designed to scavenge with VERY low-restriction systems, and most of those aren't legal or are very difficult to live with. Unless you have an exhaust system like that, headers are mostly for appearance.

67tripwr

Maaaannnn! We don't need to talk outta school! Do your "Homework"
Mostly for appearance, that is well:

Just for looks

STING67RAY

since my car is mostly a driver with autocrossing once in a while
i can deal with the stock GM sound , but i too would like to upgrade my 2" manifolds with a header to sidepipes. my current GM sidepipes then are too small. so i was looking at sweet thunder pipes. but i do not want increased decibles just better flow.
thanx for the input.