Best exhaust backbox for 3.5 V8 ?

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Nige
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Best exhaust backbox for 3.5 V8 ?

Post by Nige »

Hi,

I'm looking for some advice as to what type of backbox to use on my Mk1 Escort with a Rover 3.5 V8 (Twin SU carbs) engine :D . I have a handmade tubular exhaust manifold which run into a 2" pipes straight to the backbox. This is the same for both sides (seperate and not linked).

I'm looking for suggestions as to what type of backboxes I should use. (There are generic standard type boxes on it at the moment but they need replacing. They quieten the car too much and kill the V8 rumble). I'm looking for something which will give a good raspy/burbley V8 sound, but not be too loud. My exhaust manifolds and pipes back are all regular mild steel. Is there point going for stainless steel backboxes, or does the whole system need to be stainless for proper effect?

What would people recommend? Any particular brand or model backbox? It would be nice get peoples opinions before splashing out on two new backboxes...
Cheers


sowen
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Post by sowen »

I've got two standard cherrybombs off ebay for my rover, they seem to just take the harshness out of the exhaust note, but leave the good stuff in 8-) . They slide straight over the 2'' steel tube which I use for my exhaust pipe.

Simon
1972 Rover 2000TC M16 turbo
1975 Land Rover OM606 diesel
1984 Rover SD1 3500 Megasquirt powered
katanaman
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Post by katanaman »

If you want the V8 rumble I have always found the best way to do it is with middle boxes and no back box. The box takes he harshness out but still lets the rest of the unsilenced pipe to do it stuff. Just about every moded muscle car in the states is done this way and we all know how those sound.
Nige
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Post by Nige »

Thanks for the replies. I was thinking of Cherry bombs...Is the car not very loud though with just one cherry bomb each side, or do you also have a middle box? Are they back or middle boxes? Those boxes look very small to kill off much sound? Dont want to be heard for miles around, unless really caning it!!

Those V8 american cars do sound brilliant....Would a Cherry Bomb middle box work well for that type sound?

Anyone recommend any other types? Janspeed, Magnex, Mongoose etc? Or anytypes to stay away from?

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The Original Tom
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Post by The Original Tom »

My system is a single 2" pipe, but without the mid box and with a small back box only - it sounds ok but I'm looking to change it.

The other week I had the pleasure of hearing a twin-SU Defender 90 running 2 straight-through exhausts (looked about 2", dunno if it was linked across)

On the evidence of what that sounded like - no silencers at all!! It roared like a f*****g lion, I've never heard such a beautiful sound!

Try it unsilenced - bet you'll not be disappointed!
Rover 3.5 V8 landy - Completely rebuilt and purring... Now awaiting a good tune!!
5000SE
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Post by 5000SE »

For performance, you want the silencer as far back in the system as you can, so it's better to have just a back box than just a centre box.

To determine the 'feel' of the noise of your exhaust, the size and shape of your silencer are critical. Different silencer lengths cut out different ranges of noise fequency - that's why most production systems have two silencers, which are nearly always different sizes.

The US market is full of silencers designed to do what you'r asking, but few of them are easy to get over here. Going for the Cherry bomb is the best bet - they're surprisingly cheap, and do sound raw and burbly without beeing too loud.

I think they still do a 2" model which is cable adjustable to open up the baffles too, for those rebel moments . . . .
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Post by katanaman »

Real Steel do a whole range of American silencers from cheap to full stainless. Am not very keen on cherry bombs on their own to be honest its too raw and you just end up getting your collar felt all the time by the plod. Either way it doesn't matter what you do to a 3.5 its never going to sound like a BBC.
5000SE
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Post by 5000SE »

katanaman wrote:Real Steel do a whole range of American silencers from cheap to full stainless. Am not very keen on cherry bombs on their own to be honest its too raw and you just end up getting your collar felt all the time by the plod. Either way it doesn't matter what you do to a 3.5 its never going to sound like a BBC.
Mmm - I might have to have a look at real Steel for my own setuop - going twin outlet on the SD1 and want something 'deep but not too loud'. I see that Real Steel finally have a website yet, but it's not all that good yet and doesn't list much!
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Post by katanaman »

That's a bit harsh it must be listing tens of thousands of items specially if your into SBF or SBC. The site is naff though.
5000SE
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Post by 5000SE »

katanaman wrote:That's a bit harsh it must be listing tens of thousands of items specially if your into SBF or SBC. The site is naff though.
Trouble is, I'm not into either!

I looked for gearbox accessories which I know they sell

Hydraulic release bearings - not listed.
Tremec gearbox plugs - not listed
Speedo drives - not listed.
Their alleged range of back boxes - not listed.

I'll phone them - they're very good over the phone.
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Post by katanaman »

They will send you the colour brochures for the exhaust stuff if you want or they are all listed in their proper catalogue. From memory they do all the headman stuff turbo mufflers and the like along with the Edelbrock stainless range. The did do Magnaflow generic stuff for a while but I don't think they do it anymore.
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Post by mgbv8 »

I use the cheap Chevy Turbo mufflers from RS at about 30 quid each.
Mine are 2.5 inch straight from the collectors, no balance pipe and they poke out from under the sills just in front of the rear wheels on my MGB.
A good cheap home made system for my car.
Perry Stephenson
MGB GT + Rover V8
9.62 @ 137.37mph
Now looking for 8 seconds with a SBC engine
http://www.youtube.com/watch?v=nVscbPHgue0&list=UUqIlXfSAoiZ--GyG4tfRrjw

https://www.youtube.com/watch?v=eg3avnsNKrc&index=2&list=FLqIlXfSAoiZ--GyG4tfRrjw
mgbv8
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Post by mgbv8 »

I should have said I use the Turbo mufflers as they are quite flat and help my ground clearance. Approx 10" x 4"
Perry Stephenson
MGB GT + Rover V8
9.62 @ 137.37mph
Now looking for 8 seconds with a SBC engine
http://www.youtube.com/watch?v=nVscbPHgue0&list=UUqIlXfSAoiZ--GyG4tfRrjw

https://www.youtube.com/watch?v=eg3avnsNKrc&index=2&list=FLqIlXfSAoiZ--GyG4tfRrjw
Nige
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Post by Nige »

Hi mgbv8. Do those Chevy Turbo mufflers give off a good sound? Also, who/where are RS? Do they have a website?
Cheers, Nige
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v84x4
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Post by v84x4 »

i use a landrover td5 tail pipe which i have altered to come out the back of my landie it has a sweet burble and growl..
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