Tale of three sliencers (mufflers)

[1owner69Elan]

Having a high output engine (181hp) I originally opted to use the TTR full race systems extra large exhaust system extending from manifold, collector, center pipe, and silencer (I will use this term, silencer, instead of muffler in deference to the Elan's provenance).

The full TTR system worked out fine. I did have to have a small reinforced cutout on the frame to clear the manifold. But that has been discussed at length elsewhere on the Forum.

I have experimented with 3 different silencers as chronicled below: TTR full race, ProFab ultralight, and a FlowMaster HP2. Here are the three (FlowMaster, ProFab, and TTR) top to bottom.

The problem I encountered was that the TTR silencer is rather large and hangs down below the car to the extent that it drags on the pavement in certain situations (entering/exiting parking lots with dips). The net effect was that this dragging was damaging the silencer and causing a split in its back weld. My car does ride lower than a stock Elan which only further exacerbated the problem. I would also say that the TTR unit, with its large size and hanging so low, looked to me as an obvious "tacked-on" mod - cosmetically not that attractive IMHO.

One solution is to redo the rear silencer cavity, under the boot, to allow a silencer to be elevated creating more ground clearance. But, I didn't fancy carving up my original body.

Thus, the search for an alternative, and smaller, silencer. I first fitted a pricey ultra lightweight race silencer. Provided by ProFab (formerly Coast Fab) and also marketed under the Burns label. The fit was fine, with good clearance. But the noise was really loud. Note that I don't mind a bit of noise but this really was too much. (Jay Leno used this type of silencer on his 220hp "26R" but he had the molded-in high ground clearance cavity and used a larger silencer of this type.

The SuperTrapp units were a possibility but I wasn't convinced that these didn't restrict flow too much when configured to be not too noisy.

So, after a further extensive search, I purchased a Flowmaster "HushPower" HP-2 "shorty". This has a squarish cross section that fits nicely in the stock S4/Sprint cavity. It has much more volume than the ultralight but less than the TTR. Unlike the first two silencers, it employs what FlowMaster refers to as a "laminar flow" internal design to obtain a non-restrictive but yet quieter sound. Not sure that this isn't just marketing hype.

In any event, the Flowmaster is what is on my car at the moment. I would say that its noise level is perhaps a bit higher than the TTR unit but much less than the ultralight race silencer. Importantly, it does have good clearance compared to the TTR and is no longer grounding. Its size and placement also looks more in keeping with the overall look of the car - less of a extraneous blob hanging off the back (TTR).

I will run with the FlowMaster for now, unless and until, I see another solution that I am willing to try.

[gjz30075]

Good info, thanks. On my Sprint (same body shape in the rear as yours) I used the Thrush muffler
https://www.summitracing.com/parts/wlk-17702

Fairly small dimensions and fit the opening nicely.

They have the 'turbo' design inside, so the exhaust makes a couple of 180 degree bends to
escape. I linked to the center/offset design but am now going with the offset/offset to try
to duplicate the Sprint muffler.

[The Veg]

Interesting stuff. My Plus 2 has a similar longitudinal silencer and the current system works decently enough but will all get replaced eventually for a variety of reasons. I don't have quite as strong an engine, but the same thing applies: I want excellent performance without being loud.