exhaust

[ZOVER]

any suggestions on header and full exhaust systems for a 73 240z. I saw some at Motor sport Auto. What is the difference between a 6-2 verses a 6-1 headers. And what size pipe should I get? 2.5 inch? Any special coating?

Zover

[TTDRIVER]

any suggestions on header and full exhaust systems for a 73 240z. I saw some at Motor sport Auto. What is the difference between a 6-2 verses a 6-1 headers. And what size pipe should I get? 2.5 inch? Any special coating?

Zover

Good thread! Im interested too.

[Victor Laury]

I bought the 6 into 1 MSA header with the "jet-hot" ceramic coating. I had the 2.5'' system built by a exhaust shop well known with the Hot Rot crowd. Drove to the shop with an open header, drove back happy! I think it sounds pretty dam good. What did you think of my exhaust note TTDriver?

[JEFF]

I bought the ceramic coated header from VB. I like it a lot. I have not

decided on the rest yet.

- Jeff

[TTDRIVER]

Victor your car sounds great. Not too loud but with a powerful grunt. I liked it. What difference does the 3-2-1 header make?

Thanks

Saro Fagerian

[ZOVER]

sorry to ask but what or who is VB?

zover

[PrOxLaMuS©]

Don't buy the twice pipes exhuast setup though...

it's nice... but it doesn't fit snug at all... and it gets loud as hell. Really loud.

Go with MSA's 2.5" exhuast and you can get any type of headers.

There really is no difference in the 3-2-1 headers compared to the 6-1.

I have heard however, the longer the pipes and the smoother the bends, the more flow and HP you can get out of it.

The 3-2-1 are a bit shorter and curvier.. so i couldnt really tell ya.

[240ZX]

I believe the 3-2-1 set-up provides a little better low end power as the 6-1 in better in the high rpm range. If I understand it correctly, the 3-2-1 provides a better scavanging effect in lower rpm range. But hey, what do I know! I went with the 3-2-1 ceramic coated animals and the 2.5" exhaust (MSA Super Turbo set-up). Not to loud, but that always subjective, but you will experience a little resonance around 2000 to 2500 rpm. It's only an issue if you stay in that rpm range, not noticable passing through it. What ever one you choose, spend the extra $$$ for the ceramic coating.....it will reduce the radiated heat produced by the headers, keeping the under hood temp down. Plus, by keeping the heat in the exhaust gases it provdes better flow and scavanging. Basically, the higher the exhaust gases stay in the headers the faster the it will flow.

[Marty Rogan]

Zover,

It depends on what you have done to the '73. If its all stock, skip the header, as you will get almost no HP gains, will be a lot louder and cause more heat. Headers also are hard to fit up sometimes and are prone to leak. The stock manifold actually flows pretty well. Nissan Engineers weren't dummies. From there I would take it to a good muffler shop and have a custom 2.25" system bent, with a turbo muffler at the end. This will give you a freer flowing system, and a nice sound without the booming that 2.5" systems often give.

Now if you have an L28, with a more agressive cam, go with the headers and 2.5" pipes.

That my 2 cents worth.

Marty

[e_racer1999]

VB = victoria british... go to victoriabritish.com to get a catalog. and yes, 240zx is correct. the 3-2-1 is good for low end power since it provides better exhaust velocity (NOT to be confused with the evil and misunderstood demon that is backpressure) while the 6-1 provides the best flow. the set-up that i plan on running is the MSA 6-1 aerospace coated header with their turbo 2.5" exhaust... IMHO the best set-up

[Victor Laury]

(snip)If its all stock, skip the header, as you will get almost no HP gains, (snip)

Marty, Do you really think so? I felt a "seat of the pants" gain when I added the headers and exhaust system to my otherwise stock L-24. Of course "seat of the pants" Dynos are hard to calibrate.

[Marty Rogan]

Victor,

I am not sure how you would calibrate your pants!!!

I did see a report though, where they compared several headers back to back on a dyno. Stock motors showed almost no gain over the stock exhaust manifold. I think their L28's showed about 3 HP gain. As I recall, the NISMO header showed the highest gain. To me, a 3 HP gain is not worth all the headaches and extra noise/heat from a header.

These motors need some back-pressure too. If you reduce back-pressure too much, you can actually lose HP!

I'll have to search around to see if I can find that website again. I remember that after I read the report I decided on stock manifold, 2.25" pipes ending with a turbo muffler. My seat of the pants dyno was happy. It has a nice growl, without being too loud.

Marty