Okay, I have a header question!

[SLICKMAN]

Regarding this past post Past header post

Okay, I have a question… My 78 is stock however a stock L82 which has a high performance intake and cam (which is very respectful I may add). It’s not your stock L48… Many in this past posting above say if you have a stock engine your better off staying with the ram horns. In an L82’s case I would think this would not be the case and it would be beneficial to go with headers and would see a big increase in performance with headers don’t you?

 

[AKRAY4PLAY]

headers flow better than stock, period. it does not matter if you have an L-82 or L-48 the performance gains are significant. granted the L-82 will make better use of the extra exhaust flow as long as the rest of the exhaust system can. air movement from the carb to exhaust tip is only as fast as the most restictive part in the system. factory cams are a little on the conservative side and the stock exhaust manifolds are even more conservative. a good set of EQUAL LENGTH headers will give any shark at least +25hp, and the higher end stock motors, ie. LT-1's, may even see +40hp. this is all from my experiences with small block Chevy motors across the model line-ups.

 

[DDLS3]

The shorty block hugger headers will give you less of a performance boost than standard style headers. If you decide to go headers, ceramic coating and quality all metal gaskets are a real plus.

 

[Hijinx]

I just finished installing a set of Hooker Ceramic coated Pro Comp headers. I take it tomorrow to have the pipe work done between them and the 40 series Flowmasters I alread had.

I cranked her up today with the open headers ..... such a sweet sound! Absolute music.

Anyhow, I agree with AKRAY4PLAY. Equal length headers will give you a substantial boost. That coupled with a good intake and decent flow heads make great performance. I have an L48 and can tell you that she runs stronger than any stock L82. Now, mind you, I have put work into the heads, intake and exhaust. But, what I am getting to is that you can do well with a stock motor and a set of headers. For my money, headers, a performance intake, roller rockers, a good carb (I like my Demon) and a decent ignition will do wonders for performance on a stock engine.

 

[skeetimer]

82 Vette

What headers would y'all recommend for an 82 Vette, that would be economically priced? Where would you suggest purchasing them?

 

[AKRAY4PLAY]

Dynomax, Headman, Edelbrock, Flow Master and Hooker all make good headers. they are available through most car parts dealers like Carquest, Schucks and NAPA. mail order places, like Summit, often have them for a little less. standard painted headers will look like crap after ten minutes of run time because the paint burns off, but they are less than $100 a set. ceramic coated look great forever but cost $250ish. being an '82 look into smog regulations first, most IM areas will nail you if you have headers. there are ways of making them "leagal" like welding in a plug to screw an O2 sensor in and hooking them up to cats. if you don't have to worry about smog regs then order any set of equal length headers for a '68 to '74 Vette and they will fit yours. i liked my Dynomax headers with 2&1/2" true dual pipes and Ultraflow stainless mufflers. they performed great and sounded awesome. the whole kit was around $650 for everything from the heads to tailpipes and i did the install myself in a couple of hours. if your running a stock motor and don't plan on upgrading over 350hp stay with 1&5/8" header tubes. larger tubes lower back pressure to much and kill the low end torque. last two things, make sure the mounting flanges are thick (3/8") and that the headers you choose don't have any sharp short radius bends. if the flanges are thin, then i welcome you to header gasket hell. if the bends are sharp, the flow numbers take a dive and your wasting time and money. good luck, Brian

 

[Bill G]

I have heard negative comments about headers and the added heat in the engine compartment. I see that many people are installing them, so there must be ways of working with the heat issues.

I already have true dual exaust in my 75 L48, so would I benefit from installing headers to make it worth the time and cost?

 

[AKRAY4PLAY]

Bill,
when i pulled my stock manifolds and went with headers the engine temp dropped by 20 degrees. my car is black, the heat waves (like what you see off in the distance of a hot highway) was pretty bad in stock form. after installing the headers that all went away until i dropped in the 406. this is my only rebuttle to claims of headers adding heat to the engine compartment. i personally have not seen that, but i do live in Alaska. true they have more surface area than manifolds, but i think the drop in back pressure allows the exhaust to exit much faster resulting in lower exhaust temps in the engine bay.
as for installation, a short afternoon with handtools can get the headers installed. getting them hooked to the existing exhaust will require some cutting and welding of the midpipes. most headers drop all the way down to the tranny pan, so the hook-up point is generally different than with manifolds. there are some shorty headers that bolt directly to the factory manifold location. these headers give some performance gain, but i don't think they are worth the time and money for what you get. being you have a '75, watch for the smog nazis. some muffler shops will do the small amount of costom fitting for a nominal fee. being you already have true duals, it's your call if you want the extra 20 ponies. Brian

 

[Bill G]

Brian,

Thank you for the information. - Bill

 

[skeetimer]

Manifolds? Headers?

Okay I am confused now...Is there a difference between Manifolds and Headers? What is it?

 

[Bob Chadwick]

An exhaust manifold simply exits the exhaust from the engine. A header is a performance minded exhaust manifold.

Bob

 

[skeetimer]

Okay Thanks Bob!

 

[Hijinx]

Just put Hooker ceramic coated on my '73. Engine and interior temp is at least 20-30 degrees cooler. Actual manifold/header temp has to be down 60+ degrees. With the old ram's horn manifolds, I could not put my hand within a foot of the manifold. The radiant heat was enough to burn. I can actually fool with the plug wires (carefully) bare handed, or with gloves actually get very close.

Temp is WWWWWay down!

 

[Bill G]

Hijinx,

Laughed out loud at your quote. - Bill

 

[Hijinx]

I get more comments on that. Glad you got a chuckle at it.

 

[sscam69]

Ya know Hijinx

Now that I think about it I did notice a temperature drop on the engine bay. It was a really hot affair to work on the engine bay to do even little stuff because the heat was intense.

To be honest I don't remember the last time I worried about the engine heat. And the inside VERY cool now!

I also added header wrap.

Just as a future note for you guys going this route. If you buy headers buy them with the coating already on them. They look really good and do the same job as the header wrap. The header wrap on the other hand gets ugly, if anything spills on it it burns for a week and it rusts the pipes.

Just do your self the favor and save yourself some money (long run) and hassle and get them with the ceramic coating. Speaking from experience

Frank

 

[tonyk72]

One of my longterm projects includes replacing the entire exhaust system... My LT-1 is bone stock and don't plan on ever making any engine mods other than adding a K&N air & X-Stream filters, advancing the ignition timing and maybe adding an electronic ignition system.
I would consider headers, but am unsure of what would be best for my car...any recs?

 

[AKRAY4PLAY]

Tony,
i would run 1&5/8" equal length header tubes and 2&1/4" or 2&1/2" true dual pipes to some type of low restriction mufflers. i would also pull your stock distributor and put in an HEI style, it is well worth the extra $150 to not mess with points! MSD and others make distributors with rev limiters, nice for manual tranny cars or power shifting an automatic. if you can afford it, go with ceramic coated headers and all stainless exhaust. it will last and look good even after an atomic attack. Brian

 

[tonyk72]

I hear aluminum is better 'cuz SS tends to expand/contract with the temperature. Is there a downside to using aluminum?

 

[AKRAY4PLAY]

aluminum has a tendancy to embrittle after time. most replacement mufflers and exhaust components are aluminized, but there must be a reason you keep on replacing those coated parts. all aluminum exhaust parts expand and contract about ten times more than SS, just the nature of the metal. if you go stainless, weld all of your connections. then you will not have any problems with SS and most likely never have to replace any part of the system. stainless looks good after heat cycles, and aluminum has tendancy to oxidize and give you that white powder look.