Explain difference betwen Headers and Heat Exchangers

Rad Hatter · 10-11-2006, 07:47 PM

Headers vs Heat Exchangers please explain the difference ..
PS note I won't be using the cabin heater - ever Cheers

Bill Verburg · Bill Verburg's Garage

the heat exchanger is just a sheet metal sheath fabricated to fit around the header portion of the exhaust. Fresh air is forced between the sheath and header where it picks up heat on it's way to the cabin

Rad Hatter · 10-11-2006, 08:00 PM

So.... - what is their function? - just to provide hot air to the cabin?
I live in the tropics - would you disguard them.
My goal is - twofold

Reduce weight
Improve sound (will add a SS muffler)

I Don't track the car, and dont need any more power :-)

Bill Verburg · Bill Verburg's Garage

Quote:

So.... - what is their function? - just to provide hot air to the cabin?

correct

and yes, equal length tuned headers would be a subset of the general category headers

Rad Hatter · 10-12-2006, 06:22 AM

Quote:

Originally posted by CS119laCoS
To answer your question, if you don't need heat, you will reduce weight by getting rid of your stock heat exchanger exhaust system and related heat components, and replacing with headers.

With headers you'll need a new muffler (a "two in" to replace your stock "one in") and you can use a sport muffler. With the headers and sport muffler, you can get a very nice sound.

The bonus will be that you will also get more power, particularly if you combine it with a chip designed to work with your new exhaust.

Thanks everyone .......so what would you recommend
Any brand ?
Headers?..........
Muffler 2 in (one out ?)...dont want to modify the undercarriage

Cheers
Rich

masraum · 10-12-2006, 07:53 AM

I'd recommend SSI heat exchangers (which are equal length tube headers). I don't think the weight penalty is that great for the thin sheetmetal on the SSI's, and the heat may help if you ever need to defog the windshield.

DohertyCM · DohertyCM's Garage

The heat exchangers also disapate heat from the headers as well.
Its better to get the SSI's and a good muffler.
I have the Burshe and I am extremely happy with it (2 in 1 out).

Chris

911pcars · 10-12-2006, 09:53 AM

SSI heat exchangers are a stainless steel version of the factory heat exchangers. The factory HEs are fine too as long as they're intact (no rust-through), but they won't last as long as the SSIs (although my factory-original HEs are still alive..... not sure about my brain cells though)

Sherwood

masraum · 10-12-2006, 10:01 AM

Quote:

Originally posted by 911pcars
SSI heat exchangers are a stainless steel version of the factory heat exchangers. The factory HEs are fine too as long as they're intact (no rust-through), but they won't last as long as the SSIs (although my factory-original HEs are still alive..... not sure about my brain cells though)

Sherwood

Small correction. SSI's are stainless version of the pre 1974 factory heat exchangers which are great. The factory HE from an '89 are very, very , VERY differenc from SSI's since they are designed to connect to a crossover that then goes to a catalytic conv and then through a muffler.

GeorgeM · GeorgeM's Garage

As Steve alludes to, you must be able to get away with no cat to do the SSIs with a non-customized 2-in muffler. Some folks have custom built a cat/muffler combination, but as far as off the shelf mufflers are concerned, there's no cat in the equation.

Most folks will recommend SSIs. Not having any heat is normally reserved for track only cars and will no doubt effect resale value. SSIs are of superb quality and agree with Steve again that the weight penalty is minimal.

WRT mufflers, your chioces are many: Stock 2-in, Dansk, Monty, B&B, Fabspeed, M&K, etc. All are of decent to really nice quality and come in more than one configuration (i.e. 2in1out, 2in2out, sport, etc.). To further complicate the choice, they all sound different.

WRT the chip, you may as well do it if you're going with a new exhaust setup. Steve Wong will hook you up.

Good luck.

Rad Hatter · 10-12-2006, 06:12 PM

Hooked up with Ben at M+K who has been brilliant
Great help thanks guys

JP911 · JP911's Garage

You should do a search on this board, but many have said that SSIs are too small for a 3.2. That would leave you with headers or B&B heat exchangers with primaries measuring 1 5/8".

MIK911 · 10-12-2006, 08:28 PM

Has anyone or any company fabricated a HEADER + Catalytic combo, so it will pass the visual smog inspection in Calif? Where can i get one?

I assume catalytics are needed to clean up the exhaust gases for the smog emissions test. Otherwise a Header + Cat bypass would be ideal, so it'll pass the visual.

thanks

howie944 · 10-13-2006, 01:47 AM

Mike I would think that the combo of Headers and Cat would be self defeating.....headers allow free flow of the exhaust...The cat traps the exhaust (somewhat) to clean it. At least that's what the guys at the pool hall told me.

klaucke · 10-13-2006, 05:12 AM

Quote:

Originally posted by masraum
SSI's are stainless version of the pre 1974 factory heat exchangers which are great.

Small correction: the SSI's are supposedly based off of the 1974 heat exchangers, which where still early style. Although, obviously some SSI's (I believe) have the necessary equipment for MFI warm-up, which would only have been on ROW Carrera RS's for 74, so maybe some parts of the SSIs could be said to be based off of pre-74 cars.