Exhaust silence VS. performance

[Hummel]

Hello Guys.

I have a 2.4 L type 4 in my 1303 and i'm starting to get a bit tired of the noise in the car. My first thought is to mout a second exhaust muffler in serie with my CSP system so the system will look a bit like the system on the picture.

My concern is if this will decrease the performance of the engine ? It's a high-end performer with about 200HP at about 7000 RPM.

roadracing_anlage_ahnendorp_1599_0.jpg

Udstødning.jpg

Or will it be better to use my energy/money on a centermounted airfilter, I run two IDA's.

[wreck]

A lot of your noise will be from the IDA's, 2 twin throat carbs create a lot of induction noise. Check that the packing in the muffler hasn't burn't away , tap the muffler , it shouldn't sound hollow . I had 2 magna flow mufflers that burn't out quite quickly, I cut open the mufflers ,packed them with stainless swarf ( pot scrubbers) and welded them shut . Ended up replacing the end muffler with a triple pass muffler to quieten the engine . (102x71 with 45mm Dell's .)
There are articles on the net on how to get zero loss on performance engines and quiet exhausts .

[Steve Arndt]

The position and length of the tail pipe relative to the car body makes a big difference. Post a pic of your current install.

[Hummel]

Here are some pictures of my current exhaust.


Is there any alternative to the two KN-filters on IDA's ?? I have seen an airfilter box mounted with Porsche fan, but not with type 1 conversion. And isn't that aitbox pretty expensive ?

Thanks for the respons

One picture ended in the first post, sorry for that.

[wreck]

It's a bit hard to see in the photo .I moulded my own from fibreglass , just made the shape I wanted from polystyrene and covered it with packing tape , then layered some fibreglass with epoxy resin (doesn't melt the polystyrene) . once cured I just dug out the polystyrene . If you buy one make sure it will flow enough for your engine first , a friend got caught out with a CSP system that didn't flow enough even for a 95 RWHP type 4 .

[Hummel]

Yeah I also though that i could build my own with fiberglass. Could be fun...

Does someone have any idea how large tubes i should use for a 200 hp 2.4 type 4 ? Or could i measure it somehow?

[wreck]

I went over kill , a 4" K&N pod filter with 3" pipe runner between the carbs , have a look at other designs , I would recommend having good clearance around the ram tubes so you don't shroud the airflow into the tubes .

[type3]

I've gone for a twin silencer BAS same as you posted in the hope it'll silence my engine (T1 2332cc). Apparently the mufflers in series do a good job of silencing. I'm due fit it this weekend.

Be aware that the pic above is the older version with BMW mufflers. The one I received have BAS made stainless mufflers. The BMW mufflers supposedly robbed 8hp per muffler.

Reference threads:

http://www.shoptalkforums.com/viewtopic.php?t=62156

http://www.shoptalkforums.com/viewtopic.php?t=64662

[type3]

Yeah I also though that i could build my own with fiberglass. Could be fun...

Does someone have any idea how large tubes i should use for a 200 hp 2.4 type 4 ? Or could i measure it somehow?

You'd need to make some for IDA's as no one sells them that I could find. For the hats I'm going to mold from the bottom of a 50L plastic bin. I'm probably going to go 4 inch pipes (overkill) to an airbox from a Ford Mondeo ST220 V6.

Reason for 4 inch and not smaller is purely because Summit sell some nice Y-pipes for V8's. If I can find a 3 inch equivalent, I'll use that instead.