Ground clearance

[rficalora]

Thinking about changing my mufflers to get a better sound.  For those of you who have mufflers under the seat area and can make it over most speed bumps, how much ground clearance do you have under your mufflers?

[Burrogs]

Rob,

My car's in the shop at the moment so I can't give an exact measurement, but I'd imagine it's around 3 inches.  I've got a flowmaster and it's tucked up about as tight as you can get it.  I've only bottomed out on a couple of "monster" speed bumps, and when there is a lot of undulation in the road, coupled with bad patch jobs (a.k.a. Memorial).  It is the lowest point on the car.  Here are some pics of my setup.

[MGBV8]

Good luck with that, Rob.   I removed my front stock muffler to increase ground clearance.  

[ex-tyke]

...3-1/2" ground clearance at the muffler, Rob



Here's the overall system....

[MGBV8]

Glad I didn't have to straddle any road kill while driving your car, Graham.  My 15yo daughter did in my car (car coming the other way). We didn't clear the dead groundhog. She thought it was gross.  

What about those armadillos, Rob?!

[rficalora]

Don't have to worry about the armadillos Carl... My front valance will clear them long before they get to the mufflers

For anyone familiar with armadillos especially on the I-10 bayeau bridge between Texas and Louisiana...  Why did the chicken cross the road?   To prove to the armadillo it could be done!

[kstevusa]

My radiator hung down just above the splutter on my old car, but I address a piece of 1 1/2" angle  iron as a cross brace and PROTECTOR. I think my mufflers were at 4", but the current is low also.  I have scuffed the front cover on the parking curbs.  Guess I need "Curb Finders and Dummy teardrop fog lights" also. ;-)

[britcars]

Rob, currently the ground clearance on my car is about 30".........................got the rear suspension apart for lubrication.  
I'm quite sure the clearance is between 3 1/2- 4" and I've scuffed several monster parking lot speed bumps that have left marks on the mufflers.  I'll measure for sure when the car is back on the ground.
I have two Thrush mufflers with heat shield spaced about 1" from the floor and a home built resonator in place of the original muffler.

[MGBV8]

Round here the chicken crossed the road to prove to the Possum it could be done.

You Texans have let that varmit, Armadillo, make it all the way to Florida!

[Mickey Richaud]

Armadillo -- "Possum on the Half-Shell" :-)

They make great stringed instruments:

[rficalora]

I have 4" with my spintechs but I don't like the sound.  They are only 2.25" thick and are  about an inch from the floor board.  Thinking if new mufflers are 4.5" thick, I'll probably lose about 1.5" of clearance which would put ground clearance at only 2.5".  Maybe my car is sitting lower than most?

[ex-tyke]

Don't know if you could get this Dynamax muffler to work...3.25" thick but only a 2" inlet.....at least the sound is better than most!
http://www.dynomax.com/mufflers/super-turbo-mufflers/super-turbo-offset-offset-17803.html

[ex-tyke]

Some Walker Universal mufflers (# 17602, 17603 & 17604) with the same body dimensions, but with 2" inlet/outlet....
http://www.walkerexhaust.com/catalog/walker-exhaust-systems/universal-muffler-dimension-search

[rficalora]

Am thinking I want 2 1/2 dropping to 2 1/4" where they snake through my IRS.  That's what I had in Townsend.  I lost a lot of HP and torque when I changed to current set-up (2 1/4" to 2").  If I'm going to change the exhaust, I might as well get some of that back.

[ex-tyke]

Might as well go to chambered exhaust  like Dan Masters setup.

[BlownMGB-V8]

That's why I went to the exhaust in the rockers. No ground clearance issues from the exhaust and no power loss from the full length headers.

Jim

[rficalora]

I started out with chambered exhaust.  LOVED the sound!  Way too loud for me though. Even with 54" on each side.  I was setting off car alarms at work all over the place which wasn't good (we have parking garages so the sound echoes).  I sold that exhaust to a member here.  I even had the full exhaust ceramic coated to the back of the chambered tubes.  I should have kept it to put back on after I retire, but needed the cash.  

The spintechs are great for clearance, but don't have the bass sounds of other mufflers.  I'm hoping a regular Dynomax or Magnaflow will be a good compromise without making it a pain to drive around town.  Every parking lot around here has a bunch of speed bumps.

[MGBV8]

Might as well go to chambered exhaust like Dan Masters setup.

And Ted Lathrop & Steve Carrick.  Those things sound awesome.  Quite heavy, though.

My car is louder than is used to be. I removed the center muffler for ground clearance & I have been giving the rear one a workout for 15+ years.  I now understand Rob's comment about parking garages.  I parked in one a month ago in Asheville, NC.  My MG roared like a loin coming out of there!  A mini-van pulled over to let me by & the passenger stuck his arm out the window with a thumbs up.  It sounded like my 350 Camaro with burned out Cherry Bomb header mufflers.  Yeehaw!  

[Moderator]

Thrush Turbo is another option, made by Walker and available in the same dimensions as the Dynomax linked to above... I've run them since I built my car. Back then, they were about $20 each. Probably  somewhat louder because Thrush doesn't include fiberglass packing. I've got them set into pockets under the seats, to afford a little extra clearance. I just measured 5" from rolled flange to garage floor. (Distance from the trim/seam on the front fenders to floor is 25".)

[britcars]

Rob:
Just measured my clearance tonight and have 4 1/4" from the bottom of the mufflers to the garage floor. The measurement from the floor to the bottom of the front fender (centre of wheels) is 23 3/4".  and the rear is 23 1/2".

[BlownMGB-V8]

The exhaust is always the problem. If you lower the car 1-2" below CB height it is very difficult to get enough suspension travel to prevent grounding out when touching down after cresting, without making the suspension so stiff it is unbearable to drive. The only solution I was ever able to come up with was to get the exhaust out from under the car. That way you pick up another 2-to 3 inches of travel and everything gets much easier.

Jim

[rficalora]

QUOTE:  Rob:
Just measured my clearance tonight and have 4 1/4" from the bottom of the mufflers to the garage floor. The measurement from the floor to the bottom of the front fender (centre of wheels) is 23 3/4". and the rear is 23 1/2".

Hmmmm.  With my flares, I can't measure to the OEM wheel well opening.  I got the following measurements:
- 8" garage floor to bottom of the floor board (to the lower part of one of the ribs)
- 26" floor to top edge of chrome strip (or to the fold in the body line since I shaved off the chrome strips); measured 7" behind the door opening
- 25" floor to top edge of chrome strip/fold in the body line; measured 22" forward of the door opening

Anyway, I picked up a used pair of Magnaflow 2.5" in/out 14" body mufflers off craigslist.  At 4.25" I'm thinking they'll be ok especially if I can fit them at least 1" closer to the floors.  That'd mean at most 3/4" lower than current and only in the middle since they're ovals.  If they don't work - or if they're too loud (they're the straight through vs chambered style), I can always resell for what I paid (maybe more as they are in way better shape than I expected - they look almost new).

[burner1]

This is the exhaust I swapped to to gain clearance:

https://www.summitracing.com/parts/flo-8335408

I welded this on to mate it with the pipe and make it easily removable:

https://www.summitracing.com/parts/vpe-13171

https://www.summitracing.com/parts/sum-g4754

It sounds good too:

[HealeyRick]

Rob,
As much as I looked, I couldn't find anything thinner than the Spintechs and with a Healey, ground clearance is everything.  Mine are tucked under the seats pretty tight, but you've got to make sure you've got some good insulation in place if you get your mufflers really close to the floorboards.  I bought a self-adhesive product from DEI http://www.designengineering.com/catalog/design-engineering-inc/heat-sound-barrier to stick between the floorboards and muffler and it's been really effective.  Personally, I'm happy with the Spintechs although my exhaust is a bit loud.  

https://www.youtube.com/watch?v=6PGCoyvWUew

I think I'm losing a lot of power through my Sunbeam Tiger cast manifolds with a lot of tight turns in the exhaust system.  I think I've found some block hugger headers that will work from Summit and may change my exhaust a bit when I install them.  I'm thinking of adding some Monza resonator tips to quiet it a bit, but I'm not sure yet

Funny how important the sound of our cars is.  I have the lumpy idle I want and am very happy with the sound, just don't like losing the power.  It's all a compromise between ground clearance, sound.floorboard heat and the amount of power the mufflers steal.

[lawnvett]

Rob,

I know this is crazy by some standards, but, I raised my car back to chrome bumper height.  It was just not worth the better handling to keep fixing the exhaust.  If i was primarily interested in fastest time through the twists i wouldn't have done this.  But I had exhaust dragging issues in too many far away places.  So 2 years ago when I redid the exhaust the V6 MGBGT was put back to stock height.  I still scrape every once in a while, but no longer rip off the muffler which is now in the back of the car.

good luck