Muffler Questions

[Brian Walton]

I notice you can purchase a s/s muffler to fit the S1,2 and 3 and also a specific muffler for th Sprint. What is the difference. Is there a difference in sound. Can I put a Sprint muffler on a S3.

with thanks

Brian

[twincamman]

wellll Brian---the muffler for an ?lan is a peculiar bit of work so I just bought a tractor muffler with the same diameter pipe for 12 dollars cdn and hung it on --the sound is glorious --akin to a motorcycle on steroids -- ed

[type26owner]

Brian,
The new muffler mounts differently then the original one did on my S2. I cut the brackets off the new muffler and kludged new ones where the old brackets were located. It was not easy since the pipe leading into the muffler got in the way since it is routed completely opposite from the factory unit. Expect this not to be an easy task. It took me all weekend to do it.

The new muffler is much quieter. This just allows you to more clearly hear the induction system scream. Webers=sweet music!

[jkolb]

I have an S2 with 2 1/4 inch exhaust to the rear of the car. Any suggestions on a muffler to use? Don't mind hearing a strong exhaust note, but don't want anything obnoxious.

Thanx

Jerry

[type26owner]

Jerry,
The stock one it came with had an 1-1/4" inner diameter tailpipe and that's the same size that the new stainlees steel I put back on my S2. This the only one that's available now. As you can see the inlet pipe is different.
http://www.rdent.com/images/26s0707as.jpg

[jkolb]

Pretty little piece, but I don't want to choke back the exhaust that much. Early articles talk about using an early Jag XKE rear muffler (one of the pair). Have you heard of this being done?

Jerry

[type26owner]

but I don't want to choke back the exhaust that much.

Well if you have a stock engine with 40DCOE or Strombergs I don't think it does. I can stay even all the way to redline with Dave Anderson's Elan on the racetrack. IIRC, I think he has the 130hp twinkcam version with Strombergs. I've got the 104hp one with Webers. It pulls hard from 4500 to 6500 rpms. John Passini in his Weber Tuning book also mentions the exhaust is correctly sized for the Elan. So far everything he has stated as fact has come true so he has my respect.

By the time the exhaust gets back to the muffler the bulk of the heat has been removed and the gases under go a large reduction in volume as a result. IIRC, I looked up the flow tables in an exhaust system design book my dad has and it appeared to be okay but that was few years back.

[jkolb]

Engine is Stage III with 45s big valves, porting, and large tube headers (1 5/8 at the port). Your point is well taken about cooling and I could probably use a 2" exhaust to the rear of the car. Think I'll check with TTR to see what they recommend.

Thanx.

Jerry

[type26owner]

With that said you probably blow right past 6500 rpms too. That would definitely warrant a bigger exhaust system. My dad and I did a bunch of R&D work on our BRM Phase III back around 1970 to try and gain some performance from the exhaust system. We found the 4-2-1 manifold which is only about 40 inches long from Lotus was putting out the best torque above 7500. Back then we routinely took it to 9,500 for every shift point.

You should consult the experts for advice. BTW, the Phase III spec actually runs the smaller intake and exhaust valves. I have the 1966 original documention from Lotus SouthWest which states it clearly for the 41.

[rgwitherell]

There was some discussion of S1 - S3 muflers in Yahoo groups a week or so ago and someone came up with the DynoMax Super Turbo model 17675 which has the inlet and outlet at the same end, similar to the original muffler.

See http://www.dynomax.com/documents/super_turbo_specs.pdf

It is 4.25 by 9.75 inch oval, by 15.5 inch long with 2.25 inch inlet and outlet.

[jkolb]

When I referred to Stage III I was referring to the "modern" Stage III, with 1.625 intakes, 1.375 exhausts, and a .440 lift, 300 degree cam.

Jerry

[type26owner]

Another one! The manual in Section S depicts the wrong muffler for the S1,2 &3 at least for my S2. Both pipes entered on the same end of the muffler cannister on mine.

Jerry, I just love it when there are contradicting specifications. Suspected that might be the case though because I'm definitely out of touch for the current stuff.

[twincamman]

before you go blasting past 7000 rpm too regularly best have the crankshaft crack tested or replace it with a new steel one or it wont matter what you use for a muffler ---ed

[type26owner]

Relax Ed, the BRM just got a new steel crankshaft, new rods and new JE pistons. We never take it above 8500 rpms anymore, I promise.

I've got a whole box of mangled rods, pistons and crankshafts that look like Rohan's stuff that we kept as keepsakes.