I have a 1966 coupe (327 4 spd) non side pipe car. I recently installed the "Corvette Central under car system with block hugger (shorty) headers. I am considering going to factory style side pipes. I know I need to change the rear valance, and that the headers will likely not bolt up to the side pipes.

Does anyone know of an "off the shelf" adapter?
I will need to trim the front fenders for clearance, is there a template available?

TIA

Len

 

Len, You will need an exhaust shop to mate the side pipes to the shorty headers. No one makes an adapter that I am aware of. Here is a thought for you. Sell your entire system including the shorty headers and buy Hedman header that are designed for use with factory side exhaust. Even with this, you will need an exhaust shop to mate them together. I have them on my '67 with no problems. Someone else here on the Forum may add about the fender triming. Dennis

 

If they designed to work with side pipes; why do I need an exhaust shop to hook them up?

I sent an e-mail to Hedman; awaiting reply.

 

The pipes and collector on the header comes down and out to the side within the area that the side exhaust pipe turns in under the car. The shop still has to cut the side pipe and then weld it to the flange, that in turn bolts to the header collector. Second note; you can't use these headers if you have power steering, and if you don't have p/s, you also can't use the steering damper underneath, but it doesn't effect your steering. Dennis

 

I do not understand Bluestripe67's statement about PS and steering damper. I have a '66 SB and do not have PS but have the damper. Came that way from the factory. I also have sidepipes. Maybe hi is infeering that the shorty headers interfer with the damper. Lust curious as to intent.

 

The interference is where the collector comes out at the frame. The bracket that holds the damper or the PS is in the same position so you can't use the steering damper or have power steering. Hedman shows two part numbers, 68286 says it fits PS, 68306 says it won't. Headman can explain, I can't. When I put mine on '91 or '92 I had to remove the damper. Dennis

 

I'm not sure that the shorty headers won't bolt right up to the stock side exhaust. The ones I've seen are the same length and exit at the same point as the stock "ram horn" exhaust manifolds. I thought that was the point behind those headers, aren't they suppose to be a direct replacement for stock manifolds? A friend of mine is running stock side exhaust with shorty headers on a 64 small block car and I think everything bolted right up. A call to Central's tech department might be in order here.

I'm confused by the comment about the Headman headers not working with PS, too. If Bluestripe67 has the Headmans that have a collector that takes a 90 degree bend to meet the side pipes, instead of continuing straight back beside the tranny (like most headers), we installed them on a friend's 74 with 69 factory side pipes and had no problem with his power steering.

 

Kinda what I was thinking as well. I've had 2 sets of the Hedmans on my 67 (non P/S) and NEVER had an issue with the steering damper.

As far as a template for cutting the fender, just grab the sawzall with a GOOD blade and cut straight across.

 

I'm confused by the comment about the Headman headers not working with PS, too. If Bluestripe67 has the Headmans that have a collector that takes a 90 degree bend to meet the side pipes, instead of continuing straight back beside the tranny (like most headers), we installed them on a friend's 74 with 69 factory side pipes and had no problem with his power steering.[/QUOTE]

I'm getting confused, but can say mine are the ones that come out to the side, NOT straight back along the trans. I guess Hedman has made adjustments (based on customer compaints) in the design since early '90's. Check out the info on the Hedman website. Dennis

 

Not so much a template, but here are scans from the 1965 Assembly Manual. The bottom image has the actual data you require.

 

100%

 

I used Patriot block huggers for Vortex heads on my 383. I used Allens stainless sidepipes. Muffler shop cut my sidepipes, bent stainless pipe to fit and welded up a flange on the sidepipe. I was able to clear the steering damper bracket and retain the steering damper. Your cut on the fender tab will be covered by the sidepipe cover and moulding. You also will have to do something with the tabs that mount your rocker covers. They will be in the way of the sidepipe and its new cover. Since the body sits on top of these tabs cutting them off is the common option. I have some pictures of the setup if you would like them.

Dennis

 

I have Hedman sidepipe headers on my 66. And I have PS. You will have some small problems if you have non stock heads on your motor. I have Dart iron eagles on mine. The exhaust ports are alittle higher than stock. I needed to make some adjustments in the headers due to that fact. You can just see PS slave in this pic.

 

LDB, before you cut your fenders: the shop that painted my car told me there is a kit that has repro side pipes that doesnt require cutting the fenders. I cant find it anywhere by searching online. I remember they installed one of these kits on a C2 while mine was there being painted and it looked factory. Its probably worth a call to ask about it...the paint shop is called Performance Restorations: 210-599-8377. Also, if you find that the kit does exist PLEASE let us know about. Thanks

 

Thanks for all of the input; and for the PMs! I sent an e-mail to CC and they agree that the shorty headers are about 1/5" shorter than the factory manifolds. The guy that responded, was trying to talk me out of the side pipes altogether. I suspect that the "easy" solution would be to go with the Hedman Header side pipes, but I am not sure that I would like the look as much as the factory look.

I understand that the factory side pipes are a step backwards in terms of performance, so I need to consider that as well. I have a long Chicago winter to decide, and do the work. Thanks again!

 

i added sidepipes to my 67 ,327 some time ago. i had stock manifolds and the pipes were GM. 2" manifolds,1 7/8" GM pipes. it had the right rumble, but i knew it lacked in breathing. after much research and info from this great forum. i contacted "MCJACKS CORVETTE". he makes a true bolt on header that connects to 2 1/2" sidepipes. from forum advice i got in touch with "STAINLESS WORKS". they make a sidepipe 2 1/2" that mates to stock 63-65 2 1/2" manifolds. so i ordered from both companys. my 67 has factory a/c with alternator on drivers side. mcjacks didn't have a set in stock but said it would take about a week to make and then get coated. the parts came in as stated with instructions on how to modify the factory mount bracket for compressor. it was a simple cut off a tab on the bracket. stainlees pipes were a true 2 1/2" all the way to the exit of pipe. installation was as easy as replacing what was already there. the only,only thing i might have changed is some of the bolts that came with the headers. they had to make a tight turn to clear one of the tubes. if i used a small head bolt, maybe a 12 point,they can be longer. mcjacks kit came with all i needed, gaskets,bolts,and template for bracket cut. in all i am very satisfied with results. about the same sound. maybe a tad quieter. the car runs great,sonds good and a definite improvement in power . i hope my jabbering can give some suggestions. sorry so long winded. just my .02 cents , then some.

 

I have a set of Hooker Super Competition shorty headers on my '66 327 4 speed with factory side exhaust. The sidepipe header pipes are a close fit but the headers tuck a little closer to the block than the factory ram's horns but ultimatey, the exhaust flange is different from the stock manifold openings and the headers. That's where your muffler shop altering the head pipes and fitting a flange comes in. With these headers I am running factory power steering with no issues, it all works and sounds great (2 1/2" factory side exhaust).

Ray