Kill No Cone

iTrader: (6)

I have been trying to figure out the best setup to run. I autocross and run track days. I am putting in a carberated 85 13B. I planed on running long primaries and then thought short again. When I look at what RB offers even in the “streetport” version with two long primaries, it looks restrictive.

What do you run?
What size primaries?
What size collector?
And of course what is you favorite muffler?

Thanks for your time ~ Cone

CarmonColvin

My race car has a ripoff of the RB Road Race header and I think it is 2" dia off the motor. It collects just behind the passenger seat and is 3" from there to an Apex N1 single cat back. My next race car will have a very simular setup except I want MUCH longer primaries and will probably use a dynomax bullet racing muffler or something simular. But for a street car that might not be a good setup because of the noise.

The setup I have is very nice but for the mid range power I wanted (and you will probably want too) it collects MUCH too soon. The #$#@% exhaust shop did not follow my very simple directions and then over charged me.

The longer the distance before it collects the lower in the RPM range it will move some power. Some ITS and ITA cars go so far as to run the exhaust pipes back and fourth under the car before they collect to give them the distance necessary.

Kill No Cone

iTrader: (6)

Long makes sense. RB says that witha street ported engine your should have 120" priamary tubes. I am still trying to figure out where that locates the collector. I plan to get at the car with a taoe measure and go from there, but I have not gotten to that.

I thought about running the primarie under the axles and collecting them right before the muffler. I was not sure of a 2 1/2" collector or a 3"

thanks

Rx7carl

120" = 10 ft. Collector will be past your rear bumper.

I cant get mine under the axle due to the panhard. RB RR header. dual 2" pipes over the axle, collector next to gas tank, 3" dynomax welded race muffler. LOUD AS ALL HELL....... I'm thinkng of adding in presilencers to tone it down. Look in the 1st gen section in the presilencers thread to see what Im thinking of using. I dont care if the glass burns out, it just need a little toning down. The later you collect the pipes, the louder itll be.

Kill No Cone

iTrader: (6)

So Carl, do you have a 3" collecter. So, far I have not found one and thought I would build it.

The dynamax your are using, is it stainless?

I did not think of the panhard bar, I have one too and it just did not occcur to me that it would hit. I will have to re-think how i run the primaries.

In the other thread you asked me where to get the stainless steel wool, and I am still working on that. I looked in an aircraft supply book without luck, but I am going to keep on.

Rx7carl

Yes, but its a 2 1/4 - 3 collector. I had to adapt my 2" primaries to it. Its the flowmaster, racerparts wholesale sells it. No its steel.

Yea, thats why I had to run it over the axle, compromise was necessary. It'll NEVER get on the trailer otherwise.

SS wool- www.mcmastercarr.com $64 for a 5lb roll.

Oh and I added a supercrapp 3" tip to quiet it down for moving it around at the house.Didnt seem to do much though LOL.

If you want I have pics of the exhaust I can email them If you like.

Kill No Cone

iTrader: (6)

Man that was exactly what I was thinking!
Header, collector, and muffler. Then if it was too loud I would add a supertrap for transport.

Ya, I have been looking for the stainless steel wool and all I get is these strang comments, "you want what?"

I would like to see some photos, and thing to make it easier.

Can you get a close shop of the collecter?

So, are you going to try the "clean out the glasspack and refill is with stainless wool" trick, or just blow out some glasspacks and see if they help?

Rx7carl

E mail me and Ill send you some pics.

mcmaster has the wool, but only in a 5lb roll. So i was gonna put in the glasspacks, see if they help, even after they burn up, and if necessary, fill em with the wool. Your other option is to fill it with lava rocks instead. I might try that b4 the wool since its so much cheaper.

Kill No Cone

iTrader: (6)

Ok, I have heard of lava rocks in the muffler, but man that sounds really hardcore. Do they rattle or make vibration noise?

Rx7carl

Hey its cheap though! Only probnlem is chipping the dam stuff small eough to stuff a glasspack with it. I gave up for now. Hey email me if you want those pics!