Straight Pipes, F40 and emission tests...

By removing the cats an replacing them with straight pipes or "test pipes" it would fail most likely.
However you could simply put the the cats back on for the sake of the test. Not too difficult.

 

An F40 with just straight open pipes IMHO is way too loud for the street..
Cats and open pipes are still too loud. I didn't buy an F40 because it had this set up.
Test pipes and Tubi muffler is marginal.
Cats and Tubi should be fine. You will only gain about 5-10 HP by removing the CATS.

If you need it to be louder, use the pedal on the right.

I have test pipes and Tubi muffler on my F40. Trust me, I'm not going to sneak up on anyone..
If I get on it, you can hear it for a long ways. (I'm sure the cops can too) Cats going back on after we make the 200mph run.

Rick

 

Dang! Those are some efficient cats to only cost 5-10 hp.

 

Yep. But removing the factory muffler and installing a Tubi was good for about 30hp. The Tubi muffler only cost 10hp over no muffler at all. I guess that's why they sell so many.

Rick

 

What is the design of the Tubi muffler? Straight through with perf turbing inside?

Most of my turbo buddies have had the best luck with mufflers designed like that as it keeps backpressure down. As Im sure you know, backpressure is the enemy! When I dropped my backpresure from 43 to 24 psi the car picked up over 50 whp and that was on low boost!

 

Norwoods just built some ceramic coated straight pipes for an F40. They said it sounded great, and wasn't that loud.

 

sorry, can't answer your question - but this is a really modded F40 if you wanted to check it out: http://www.ferraris-online.com/cars/FE-F40-90568/main.shtml

 

What kind of car were these back preasure tests done on?

The Tubis on my car are the same as the ones in the link above.

Rick

 

I guess one would have to define "That loud"

 

Andrew ,
The tubi exhaust you were talking a long time ago on the Enzo?
Did he did it?

 

Andrew -you've got the following options

Cats:
1. Test pipes
2. Silenced test pipes

Muffler
1. Tubi Intermediate (muffler)
2. Tubi LM (open)


Every F40 owner (bar one) we know has gone for test pipes w/LM Tubi - which is for max volume and straight through.
Personally I agree with Rick -it IS too loud for the street - but frankly it's utterly devastating and the only setup I would have if it were my F40 but then I'm different.

We had one chap who was worried about excessive noise so he bought the silenced test pipes but still got the open LM muffler...

P.S. Removing cats with either of the two options above WILL likely result in emissions compliance failure - particularly I'm guessing in the USA. Some good extra power to be had though with either.

 

what's wrong with lots of noise? there's no such thing as too much! Just make sure you wear a sound deadening headset when you are in the cockpit.

 

Get a PO Box with MailBox etc in Florida. Register the car there and have them forward your mail to our NY address.

No smog check....No Problem.....Thank You Jeb Bush!!!!!!

 

Not an F40 (it was my 2.2L 16V Turbo Dodge which might not be F40 "robust", but it does make something over 400 hp to the wheels on a Dynojet)....but all turbo cars are the same. Less backpressure = more power. Ive tested this a few times (its quite easy to measure exhaust manifold pressure) as I have been trying to keep the boost/backpressure ratio around 2:1 in my car. Even lower is better, but inevitably spool up is affected. When you can actually get the backpressure less than boost pressure, then youve really got something wild and power will shoot through the roof.

 

Or, all F40 owners can "store" their cars in my FL garage and Ill be happy to take "care" of them.

 

Back pressure can kill the performance on a Turbo. I pulled the cats, changed the stock exhaust and tweeked the waste gate on my 911 Turbo and got a 30-35 HP gain easy..what goes in....must go out...they easier, the faster, the better....

 

Heck yes!

When my 2.2 was bog stock (and I mean bog stock down to the paper filter) it made a measly 185 whp. I never ran mine at the track like that, but on street tires they generally run in the very high 14's.

I yanked the crappo factory exhaust (which I swear they did everything but stuff a banana in the tail pipe in the quest to create a restrictive system) and ran a 3" system with no cat and an Ultraflow muffler. (Ultraflows are very good for turbo cars...straight through design that actually creates LESS backpressure than an equivalent length of 3" diameter exhaust pipe!) Just yanking the exhaust and doing nothing else bumped power up to over 250 whp on the dyno.

Replacing that restrictive stock turbo with a more suitable unit took power to about 310 whp...again still at the same boost pressure.

Thats 125 whp with no real change in boost pressure (still around 13 psi), the "LOW" boost setting on my controller. On street tires a few weeks back, the car ran [email protected] like this (i.e. low boost). Thats nearly 2 seconds quicker due almost entirely to the reduction in backpressure.

Then, with a flick of the boost controller to "HIGH", its another world as boost doubles

 

Sorry my experiences dont relate to an F40 specifically, but turbo cars all act the same. Drop the backpressure and even youre buttdyno will feel a big difference.

Id imagine on an F40, the results of dropping backpressure are going to be even more magnified than they are on a small engine like mine.