Hello,

For my 78 L48 Vette, I've decided to do the whole exhaust system by doing the following

Front Y Pipe 2.5"
High Flow Cat 3"
Rear Y Pipe 3"
2 Flowmaster 40's

I was wondering wheres a good place to look to find Hedman Headers 68301 for the cheapest price?

To my knowledge I should remain smog legal in CA with this setup.

As of right now I have stock exhaust with two flowmasters and I am disapointed with the sound, hopefully this makes it better.

 

I'm running the stage two exhaust on my 72 with headers.

I love the way this car sounds and I can upload a video tomorrow night so you can hear it.. sounds great!

I can't load it today, I'm out of town.. I'll try though...

I'd look at Jegs or Summit for the headers and if you have a/c you'll need that passenger side bracket.

Willcox

Willcox

 

Cool I would very much appreciate that!

 

68301 Is the part number that I use on my 76. Use the stock AC bracket not the cheap flimsy, after market one. Hollow out the inside to make room for the tube, and use spacers. I have used these headers and this bracket ever since my 383 went in. in 25K very hard-driven miles and thru 2 sets of heads, I still use the oem ac bracket.

 

$340.46 http://www.autopartsdealer.com/hedma..._content=rank1

 

If your car is equipped with the EFE heat riser you will also need either one designed for headers (Doug Thorley headers makes one) or adapt you existing one - hedman makes an adapter, which I have never used - I use the doug throley one.

Your EFE is vacuum controlled so you would need to extend the vacuum line down to the new efe valve which would be mounted on the passenger side collector.

If you can afford a system fabricated at a shop, it would behoove you to have a smooth 'y' transition fabricated for both the head and tail pipes as the factory configurations are hardly designed for free flowing. while you are at it you could have the head pipes y into a 3" single pipe and 3" cat which will increase your flow a bit more.

this is my rear y-pipe goes from 3" hi flow cat to a smooth transition to 2 1/2" tailpipes



the hi-flowcat 3"


the front y-pipe 2 1/2" head pipes smooth transition into 3" cat.

 

How hard is the installation for these headers? and what are the required tools? I apologize for the really newb questions, Im really new with cars and I'm learning as I go.

I am wondering where I can save money by doing the installation myself without special equipment.

If it wasn't too difficult I was planning on installing the headers myself, then having the muffler shop do the pipe bending and installation of the Y pipes and muffler tips since I already have the flowmasters on.

Once again thank you for all the help you guys have provided already!

 

the headers are fairly easy to install, you will need new gaskets and bolts- a 3/8" drive ratchet with the correct socket size and a combination open end-box end wrench of the correct size.

These hedman hedders have a typical clearance issue at the idler arm, Ive heard of only a few people who didnt have to dimple these headers at the idler arm to prevent the rubber boot from touching and melting against the header.

Dimpling is an easy process, I use a disposable socket or other round item wrapped in a shop towel - held in the correct position a few authoratative blows with a hammer will create the needed dimple in the headers.

You will want to install the headers from below, it may be possible to do the passenger side from above but there is much more room for install below. so floor jack and jack stands are called for. You may find it easier to install by removing the spark plugs.

If you are not removing the original head pipes (from old manifold to y-junction) then you will need to cut these pipes so that the headers will go in, you wont be able to connect them to the headers. Cutting can be done with a hacksaw (lots of effort) or you can rent a pipe cutter from a local autozone (fairly quick and easy).

you will be running open headers to the muffler shop if you were planning on driving the car there.

 

Thank you Fauxrs! you have been very helpful with all your replies! Do you happen to know what kind of HP/TQ numbers I'll be looking at with this type of exhaust and the installation of a new intake manifold, air cleaner, headers, cams. I've been researching numerous sites looking for ones that will keep me within range of being smog legal.

 

Mostly this depends on your choice of cam, by themselves the headers and the edelbrock performer intake (with egr) wont really add up to a lot. If you do get smooth y transitions to a 3" pipe and hi-flow cat you might see as much as 15-20 hp increase to your factory 185 hp.(even more perhaps if your car is still equipped with the OE pellet style convertor)

The real magic begins to happen when you dispose of the anemic bumpstick in the L-48. Though I have never installed one, the comp cams High Energy 268H (COMK12-210-2) is an E.O. numbered performance cam for your application, which in combination with exhaust, intake, timing and carburation tweaks might put you close to 300 hp.

Besides the camshaft the heads on the L-48 are also a major stumbling block, as is also the dished pistons and low CR

 

This is a very good point. If you decide to use Hedman Headers be warned that they have had quality issues of late. Before you pick up a hammer and start "dimpling" make sure that's all you have to do. I as well as some others have had issues with the fit of Hedman Headers of late. If you read old posts on the forum most people have been very happy with the quality and fit. That's why we choose them in the 1st place. Well the fit at the idler wasn't even close. We called Hedman tech line concerned with the pour fit and they said it just needs a "dimple". It looked like it needed more than a "dimple" but Ok. Well it needed more like a "smash". Now we get it on the head and the collector is "aimed" wrong. It was angled at the ground. Call back Hedman and they say "can't help with that you modified them". Wait we modified them at your advise. Make a long story short the R/S header had to have a "dent" way too deep to get past the idler arm and the pipes had to be heated with a torch to get the collector facing the right way. A torch doesn't do the coating well so the header had to be recoated. All this at a much added expense. I will tell you this I can't wait to replace these headers once I have the money and you can be sure I will never buy another set of Hedman Headers. What's the bottom line? I'm just trying to give you a heads up. What ever header you buy just remember once you take a hammer to them you own them and it doesn't matter if they are built wrong or not. I'm not saying a little "dimpling" is wrong. I would go as far as to say it's normal. But it should be a "dimple" and no more. Otherwise I would suggest a different brand. Either that or be prepared to buy a set of uncoated headers and do what you have to do to get them to fit (which could involve cutting and welding as well as additional expense) and then have them coated. Again this is meant to be a "heads up" not to scare you way from adding headers to your car. Good luck with what ever you choose.

 

Hello 3JsVette,

Thank you for your information! I'll take that into consideration, alot of the information I am getting I am making sure I know it before I do anything to my car, as of right now I'm doing my research. I don't plan on doing anything to my vette until mid or end of May. By then I should have enough information to do my exhaust and top end build. This forum is very helpful and the people on here are very informational to a newbie at cars like me.

 

3jsvette is correct, the hedmans quality seems to have slid at least based on posts here, mine were used when I bought them like 10 years ago. below is a picture of the clearance I had before dimpling

 

Great picture! I would have been thrilled if that's what we had to deal with. A "dimple" takes care of that. I'm telling you the set we are stuck with the R/S header was not even close. It wouldn't even bolt to the head.