Mufflers

yes, they are called straight stainless pipes.
Seriously most of us ditch those mufflers since they rust out like crazy. Run stainless straight back to a magnaflow, or similar, at the very back then weld on a set of tips.

 

I STRONGLY suggest you contact Timevalve in Florida. Did an Ansa style stainless system for my 400i complete with Ansa stickers for a reasonable price.

Timevalve Manufacturing - Stainless Steel Exhaust Systems and Catalytic Converters for Mercedes Benz, Vintage Ferrari, and other Classic Cars

 

GT Car Parts in phoenix has the replacements for sale.
I think they quoted me about $470. for each back muffler, with the chrome tips as original.
I drove a nice 400i with the stock six mufflers and it was so quiet you couldn't tell it had a 12 cylinder in it.
When I did mine, I ran straight pipes to the back mufflers and I am quite happy with it.
It is a bit loud, but it should be.

 

Question for you guys that have deleted the mufflers ahead of the rear axle.....are you running 2 pipes per side to the rear ? Or a single pipe with a y pipe at the headers ?
My '85 already has a y pipe joining both headers to a single pipe all the way to over the axle and a DynaFlow with single tip at the rear...also the side exits off of the headers are capped off.
A future project is to change to twin outlets on each side....would there a gain of "sound" to switching to double pipes to the rear with a 2 in & 2 out muffler ?
Just wondering out loud....exhaust is way down my list of projects....Thanks !
Gary

 

Hi Gary,
My car has true dual exhaust, meaning it is 2 separate systems all the way back from the headers.
I have seen the system like you describe but I think you'll find most of us are running 2 sets of pipes and mufflers behind the axels.
Let me know how I can help.

 

Can anyone with a non-stock system post a video of their car at idle and while being revved?

 

Dave....PO or possibly the EPA shop installed 1 cat conv per side with a Y pipe joining 2 headers on each side to one single straight pipe going to the rear and over the suspension. One of the first things I did was cut out the cats, (one was loose & rattling), but I still have the single pipe.....when I get to it, would it be better to run 2 pipes , one for each header, per side, back to the rear ?? Would there be a different sound running 2 or 4 pipes from front to back ?

Gary
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Gary, you've got it. Run 1 pipe from each the cats back. So a total of 2 pipes, 1 per side, back to 2 "mufflers" or resonators behind the axles.
Do a search on my posts. I listed the parts number of the stainless mufflers on my car. If you can't find it just let me know and I'll crawl under there and get you the part number.

 

Gary
It looks like you have air pump and O2 sensor. Did you consider a cat without the air pump? I believe new cats do not need the air pumps.
Ken

 

I'm running 4 pipes from the front to rear.

 

Ken...we have no inspection or sniffer tests here in sunny south Florida...so, no cats on the car, just 2 on the back porch chasing lizards ! The converters are already gone, the air pump wil be removed also.
I am just thinking of doing 4 straight pipes to the rear or 2, if there would be a different sound...would it be worth doing.

Thanks, Gary

Thanks, Dave....I need to decide on the pipes first, if I stay with single, then I don't change anything.

Jim...any difference in sound with4 pipes, or did you always have 4 to begin with ?

 

What exactly do the o2 sensors do in a converted car? Did the euro car have o2 sensors?

 

My '84 400iA has OEM Ansa mufflers I put on a number of years ago. I addressed the rusting muffler issue by using it regularly. They weighb75 lbs per side! A real pain to install by myself.

The car had cats with 2 inlets and 2 outlets on each side plus the rearmost factory muffler. These them mated correctly to the factory rear pipes. It had O2 sensors connected to a Bosch electronic box under each rear seat cushion. It regulated the fuel flow in the K-Jet injection. All of this is long gone plus the air pump (a Ford part!). The engine/exhaust is now as it left the factory with the addition of an MSD ignition box replacing the noisy Marinelli box.

 

Just procured a 412 automatic convertible - does anyone make a pre-formed pipe to run between the headers and the rear exhaust (to eliminate all the mufflers?). The engine is way too muffled! Right now I have four sets of midpipes per side running back from the headers (what I believe to be the stock setup - way too quiet, way too heavy,and way too prone to accumulating water). I may just have a local shop fab some but figured I would ask. Thanks in advance.

 

Nothing pre-fab that I know off, but not difficult for your local muffler shop to do..look at my pics above in this thread, I already had the single pipe on each side, but I did have them cut out the cat converters and use the short stubby "y" to put 2 headers into 1 pipe all the way back. Behind the rear suspension the pipe kicks up and into a single muff per side with 1 outlet..it's a little loud, but ok for now.
PS: you can see the shadow of the original mufflers above the pipe where they sprayed rust-proofing..the car came from Vermont.

Gary
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I went with a crossover system; from the headers, take the 2 pipes into a crossover 3.5x7" oval muffler (Magnaflow 11148) that exits with a single 3" pipe, then reverse that back with an identical muffler that goes back to the (2) pipes (1.75" each, I think) that will thread its way to the resonators...I get just enough boom to set off a few of the car alarms in the parking lot at 1500 rpm, any faster the whole thing evens out and is not at all quiet, but I can roll up the windows and not feel the car drone...
The easy way ? Run 3" glasspacks under the car...I know this sounds like something you should do on a Chevy, but the original muffler design was practically this (there was a crossover after the first resonator, but for all practical purposes this is 4 separate exhaust lines that roar out the back and give the Ferrari that rock-and-roll sound...
Getting mufflers to fit under the car is not easy, ground clearance is not generous on these cars....Lee

 

Wow Part time...that exhaust is just SCREAMING to be redone. That engine deserves so much more.

 

Dick Fritz of Amerispec in Danbury, CT, installed new cats and removable "test pipes" <cough, cough!> for my 400i when I bought it. I installed the cats when I needed to go for emissions testing (before the car was 25 years old) and then could swap them out and replace them with the test pipes in about 45 minutes without using a lift.

There was a noticeable improvement in the sound with the test pipes connected to one muffler on each side and the resonators by the tail pipes. Louder, but not objectionably so. I don't know how loud it would have been with only the resonators and no mufflers, but I would guess it would be uncomfortable for any kind of long drive of more than about 15 minutes.

Fabricating the test pipes is not a difficult job and should be able to be done by any competent muffler shop

 

Here is a picture of the exhaust on my 84 400i. Has twin inlet cats and o2 sensors with exhaust gas hoses going to the air pump up front. Then two outlets from the cats to a pair of "cherry bomb" type mufflers on each side. Then, continuing dual all the way out the rear (without rear mufflers) to the chrome tips.

Honestly, I really like the way it looks without big backboxes (rear mufflers) hanging under the rear of the car.

Yes, in the picture you can see a missing exhaust mount and hanger. From my records this exhaust was fabricated in the early 90s by a shop in California.
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Boy isn't it interesting seeing all the slight variations?

 

I'm pretty sure we haven't seen the half of it out there

 

Here's Ferrari's cross-section technicals:
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