glhs0867

rxtuner79

Just do what I explained in those PMs. You're making a race car. Just do up the RB header.

I think I have one of the fastest n/a s4 stock port car here. and you will also.

rxtuner79

iTrader: (1)

I know, and I'm seriously considering it, but again I'm just concerned about the weight. I know you said that the weight is needed because of durability and heat issues, but the SDJ headers are only 9 lbs and I've heard nothing but good things about them. Not to question your knowledge, but I am trying to get as many different views as possible.

glhs0867

I understand buddy.

nothing wrong with what you're doing.

if you go with plexiglass windows IE: side and back those 9 lbs won't matter too much.

With you're first race winnings you can buy the expensive one and give us the skinny on it?

PvillKnight7

iTrader: (16)

Why waste the time? The hard engineering part is already done for you...Just copy a design that is known to work well. It will get you close enough for a lot less $$$

evileagle

iTrader: (1)

a stainless steel header vs. the stock header/cat assembly?

I'd say the difference is more than that.

rxtuner79

iTrader: (1)

I think he was talking about your catback compared to stock, eagle.

ericgrau

iTrader: (1)

Custom fab the whole thing out of thin titanium sheet. That way when your aux ports stick, you don't make any power and it leaks, you won't be able to admit it to yourself b/c of all the money you dumped into the system. Instead you'll be saying, "My custom made titanium exhaust gives me more power than a turbo."

Only NA drivers could give something like this so much attention. I mean, the exhaust is all we've got. I'm gonna keep mine simple and just admit that there's no hope beyond that.

cool_as_crap

No, catback

How can you say that is not bullshit?

I know the entire exhaust would drop more than that.

PvillKnight7

iTrader: (16)

lol

NoDOHC

Actually, I have had the entire exhaust of my car, still bolted together (except the manifold) and it weighed 45 lbs.

I guess it is possible to have a 36 lb savings, if the entire exhaust system weighed 9 lbs, not just the headers. Very thin pipe with no mufflers or cats might sneak under that mark.

Maybe the manifold weighs enough to make these savings possible. I will not say that it is impossibe to save 36 pounds on exhaust, I might argue that it would be difficult to maintain good hearing and save 36 pounds on exhaust.

evileagle

iTrader: (1)

Having weighed both of them I can know that the stock exhaust weighs quite a bit, and a thin-wall stainless replacement is much less. Though the exact numbers escape me at the moment.

PvillKnight7

iTrader: (16)

have you picked up a stock header?? its a brick

Black91n/a

It's a manifold, not a header.

Having done exhaust on my car I can confirm that the stock system weighs a ton and a half.

chrisfc3s

rb sells a header kit that you can make 2 in 1 or do true duel if you can weld and have a lift make your own.. its not that hard i got an 88 na and used the factory manifold and did a 2.50 pipe w out cats presilences and all the emission carp gone

rxtuner79

iTrader: (1)

Again, I'm trying to stay away from Racing Beat because of the weight.

When I get my exhaust... whatever I get, I will have both systems weighed to we can have some hard numbers to go by.

I'm still looking for someone to chime in who has a custom setup, but again i would like to thank everyone for their help. Let's see if we can keep this thread going so people can have a good one to look at while searching.

anewconvert

iTrader: (1)

we are talking about a few punds here. Unless you are competing in a racing series that offers serious money or sponsorship those pounds arent going to mean anything. All you are asking for is a really expensive custom header with questionable power production so that you can shave a few pounds. the dollar to benefit ratio here is WAY skewed away from benefit. If you want to make up for those extra pounds spend the money on some super lightweight wheels, or move the battery to the passenger storage bin. This is just a pointless expense even for a dedicated track car.


BC

phoenix7

if you're worried about weight, why don't you make the tubes come out of the hood. Straight up. Why are you worried about the weight? Have you successsfully lightened the rest of the car?

JunpoweR

iTrader: (1)

The racing beat headers are thick for a reason.
They last long and sound great.
Any thinner on the materials and you will get the tin can noise.Sounds like there is something rattling inside.
Thicker steel means it will harness the combustion slightly better and you will have a deeper exhaust note.
If you dont mind the sissy sound from thin metal then go for it.

What would be nice is a exact replica of the RB headers in Ti then I would go for them.Might be pricey but I would throw down $500 bux on those.

DaveB

Unfortunately, Stan doesn't seem to be in business any longer. I bought his IT/Prod header a couple of years ago and am completely satisfied with it. I read on one of the discussion boards that someone else is now producing the header under license from Stan but I am not completely certain this is the case. His origional header was made up by a NASCAR shop to Stan's specs and it is absolutely a piece of art. The welds on it are among the best I have ever seen. Be sure to get the one with the small tube that connects the main tubes about 10" from the port. Stan claims that this configuration opens up a fair amount of available torque under the curve, and for autocross, this may be a real consideration.

glhs0867

Have you ever run your RX7 with those headers on a quarter mile track? what times did you get?

Have you ever dynoed your car?

I see a big issue with the pressure waves with only 10" before collect, not only does the pressure waves bounce back in the exhaust port, but you lose most of the benefit of collect with only 10" before collection.

With this design I see a big loss in the higher rpms as the pressure waves are slamming into one another, before they can get far enough away from the supersonic pressure waves coming out of the port.

However, being shorter would work good below 4000, with an increase in TQ below 4000, and a loss above 4000. thats the way pressure waves act.

Roen

iTrader: (2)

Not to bash, but RB's header is only good for the street. They're **** on the track.

Speedsource, ISC Racing and SDJ headers are the ones for the track. I still think the road race is still the best exhaust for the street.

glhs0867

Thats funny!

Do you have any real data about what you just said?

I would like to know.

fcdrifter13

Sdj Ftw

rxtuner79

iTrader: (1)

I know it's only a few pounds, but like I said it all adds up in the end. The dollar to benefit ratio of a custom setup is exactly what I'm looking for, which is why I made this thead.


I haven't done any weight reduction to the car yet, but once I get another daily driver I would like to remove anything that is not needed. But for right now, I need every advantage I can get.


I see where you're coming from, but I don't think this is the case with the SDJ header. There's a couple videos on youtube of 1st gens with an SDJ header and they sound nice while still having that "rotary buzz" kind of sound. Also, I haven't heard of them not lasting long despite their weight/materials.

DaveB: www.rotaryinnovation.com has the rights to the header, and I'm pretty sure they produce them now.

Roen

iTrader: (2)

Search C. Ludwig, I forget which thread we talked about this. It's due to the sharp bends that RB has on their headers. Plus, it's funny that none of the ITS FC guys that are winning their division, run Racing Beat Headers.

As I remember,

Speedsource made the highest power with their short primary header. (174 whp)
ISC had the best power in the midrange, up to 5500 or 6500, I forget.
SDJ wasn't tested, but popular opinion is that it wrecks Racing Beat as well.

By wreck, I mean maybe 2-3 horses separates the bunch. =P

I think the Road Race made somewhere in between 170-172 whp? or slightly slower, I forget.

Mind you though, this is on stock engine, stock computer, with a cone filter, I believe it was a K&N. Once you port the engine, then you'll really see the differences. Plus, Speedsource in the past had a long primary header system, but I haven't seen any data from that. Just because it's the most popular, doesn't mean it's the best. I mean, how many of you guys know the major winning race teams in ITS racing? Those are the guys you should be following, since they're doing whatever it takes to squeeze out every last horsepower from the stock engine.

However, I'm still of the opinion that the Road Race is the best street exhaust for the NA.