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Ricardo_Julio
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I've been reading for a while how bad, horrendous, inferior, etc, etc the JH factory exhaust header is; Can someone tell me why that particular header is no good, I have two of them and wanted to ceramic coat one of them but will not do it if that is to be a waste of money and time on an inferior product.

Chris E
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 I don't know what the difference in performance is, But as far as removal & installation there is a quantum difference with the aftermarket unit being much easier to work with.

 

Chris

JodyKerr
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I start with quality. I'm certain that 30 years ago, when these were new from the factory that the exhaust manifolds were perfectly adequate. Not great, or even good, mind you, but adequate. 30 years later they are very brittle. Th efacing plate (that mates up to the block) is generally fine, but the tubing quality, paired with 30 years isn't. The engles inside the headers means that any water that would/could collect did, and caused many headers to rust out from the inside. Additionally, 30 years of vibration causes a lot of stress on that tubing, resulting in cracking and stress fractures. To add insult to injury, they're very difficult to weld well because of the porosity of the tubing due to age.  Also, as was already mentioned, it's a royal pain to fit/remove these headers. (I've been there done that on all of these items with multiple exhaust headers)

Because of these items I'd be very leery of any factory header. You may be lucky and have one that wasn't used, or is from a very low mileage car. I would definitely spend a lot of time going over any original header before using it (and then only using it if I were trying to be either a) cheap or b) original). If you're going to spend all the money to have it ceramic coated, I'd also have it properly checked for stress fractures (like they do on engine blocks, etc).

When it comes to performance, all those bends and such in the stock manifold simply create a lot of back pressure on the exhaust. for every twist and turn it gets worse and worse.

If you're going to spend the money to do the coating process I'd highly recommend going with the performance headers from Delta. They're worth the money on ease of installation alone, plus they are good for a few extra horsepower because of more efficient routing (I forget what the claimed amount is).

Jody

Ricardo_Julio
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Thank you both Jody and Chris, you guys are a wealth of knowledge; Thank you again for keeping me from making a bad mistake; Now....I have TWO sets of JH factory headers for sale.....any takers?  They're cheap.

JodyKerr
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I might have a taker on at least the outer header. A local fellow has one that's quite badly cracked on a car he's trying to sell.

Ricardo_Julio
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I have it, don't know how to ship it.
 Tell me how

Jensen Healey
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I doubt if the aftermarket headers make 2 HP and if they do, it's at the detriment of the torque band. Unless someone does the dyno comparison they are equally good.

 

Grassroots Motorsports Magazine routinely dyno’s exhaust setups and there is no major percentage improvement over stock headers. Sometimes there is a HP and torque reduction!

 

If you’ve built an all out performance monster, get the Delta headers. If not, you may not notice the difference, after all, you’re not replacing cast iron exhaust crap, you’re replacing a header with a header.

 

Kurt

 

Greg Fletcher
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Just an FYI, the matched performance version is no longer available and hasn't been for some time. Low demand tends to thin out those kind of products. The basic version is very good and has been refined many times over the years. It's a vast improvement over the factory header and is easier to install.

Also, a note on the ceramic coating- you'll need a brand new unit to get it coated inside and out at Jet Hot. Otherwise, they will bead blast your used one and coat only on the outside. Big advantage to having a new unit coated inside and out!

jcdean
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Greg is wise.

It is almost unbelievable how much cooler it is with the Jet Hot coating applied.



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