RRTEC

iTrader: (13)

I spent 3 hours last night pooring over the archives and the search oblivion, to come up with 100 or so half answers and 50 or so post of pure babble.

I have a LARGE modified RB header for my 2nd gen 13B that is in my Track car. The total length of the header is actually 6 ft long!!! They are two seperate tubes all teh way back. I am thinking of putting 2 stainless OBX fart in a foldgers on the end of each pipe and tapping in an o2 bung. Anyone have a solid # on the gain from running true duals? Also what are the drawbacks?

thanks

trevor

DriveFast7

iTrader: (1)

You want the pipes to collect so you can get exhaust scavenging affect.

calvinpaul

iTrader: (2)

What does that do? And what is the difference if it collects at the header or at the muffler? What are the pros and cons?

vipernicus42

iTrader: (4)

It would seem to me that the exhaust scavenging effect would be less pronounced on a rotary... or at the very least, not as important as the higher flow offered by true duals... though the car IS just a 2nd Gen 13b...

Honestly RRTEC, I can't offer any more than the speculation that you've already found. I would *guess* that going to true duals would only offer gains on engines which require much larger flow... Is your 13b ported?

Jon

SS124A

LONG primaries have a propencity to be MUCH louder than a short primary set-up.

Long primaries also shift you power band up, you may get a higher PEAK hp # but the car won't necissarily be any faster.

I would suggest against a "true dual" set-up, esp on a street car
.

REVHED

Long primary = pressue wave tuning for low rpm while short primary = pressure wave tuning for high rpm.

As for the noise issue, it really comes down to pipe thickness and muffling not header length.

RRTEC

iTrader: (13)

This is a track car that will ONLY be driven to the track and also to local meets...

DriveFast7

iTrader: (1)

Checkout both exhaust tech articles Trevor, VERY good read.

http://www.yawpower.com/techindx.html

Anything n/a other than peripheral port should have long primaries that collect way back. Check out the RB catalog, has a good article on it there too.

RRTEC

iTrader: (13)

Hey great read, Thanks Brad.