i think i might end up going with that, since im also using a bridged 6 port. and the racing beat 48 dhla. how restrictive is the 2.25 inch for it?

 

There are three ways I know of to make good power with a bridgeport. A long primary system... a short primary system... and forced induction.
Long primary systems have a broader powerband, but are not very tolerant of muffling. Short primary systems have a narrower powerband and are slightly more tolerant of muffling. You should not put mufflers anywhere in piping until after collecting the primaries or the tunning will be destroyed. The mufflers should also be placed a reasonable distance away from the collection point. Racing Beat has some good info on the specs for these systems in their catalog. It is a shame that they do not make any systems that match their specs. If you are going to run a bridgeport on the street the only system that has a chance of making power and being somewhat quiet is the short primary.
Forced induction like a supercharger throws everthing out the window though. It can make life easier because it pretty much eliminates the need for tuned exhaust scavenging. The positive intake pressure is always there so you don't need timed low pressure pulses to scavange the chamber durring overlap. The pressure just blows it clear.

 

Since we're talking about exhaust, there have been several discussions (not in the forum) on which one is better for a dual pipes into 1 muffler.

1. Collector before the axle.
2. Collector above the axle.
3. Under the axle set-ups.

I have personally tried both 1 & 2 but I cant tell the difference. #3, I have no plans of using.

 

Under the axle is often chosen when space is not available for a proper free flowing exhaust routing over the axle.
As for before, after or at the axle... It really depends on where your tuning point will end up.
If you intend to use a long primary system for a bridgeport to RBs specs you will want to put your collection point ~9-10' from the engine. Depending on the length of the car this point can end up before, after or at the axle.
If you use the short primary system you will need a header that collects equal length tubes in ~1-1.5'. This is well in front of the axle. You have a long length of pipe left to choose where you want to put a muffler.
I like to split the flow into two smaller pipes. I am of the opinion that two smaller ID mufflers are quieter than one big one of equivalant cross sectional area. Also you won't loose as much ground clearance.
In either system shortening the collection point pushes the tuning point up in the RPM range and hopefully the rest of your engine works well there.

 

Just buy your neighbors some ear plugs...

By the way... Does any one have any dyno slips with two RB mufflers one in front of the other?...

 

No dyno slip, but the RX3 did high 12s @ ~108mph in the 1/4 with my three muffler short primary system and the stock tall gears. Changing the gear livened it up quite a bit but I didn't run it on the 1/4 again.

 

Getting a Bp bareable ,nevermind quiet,is a hell of a mission,without loosing allot of performance.To be honest,i dont believe it is possible at all.

Way back in the day i used a 2.5 " short primary ,going through 3 silncers,to try and quiet it down.The end result was just a nice loss of Hp ,and i kept on blowing up the 2 middle silencers ,so i went back to a single silencer. Ears didnt like it,but holy hell it made a big difference in performance.

Next Bp motor will have a 3" system ,with a single silencer ,as that is all the beetle will have space for.Ear plugs would be required.

Besides,being the loudest car at the track,is fun!Even if you are road registered.

karis