Okay this is what I want to know, ASAP
I have a fuel injected TP wagon and what I want to know is if I can remove the rear most (under the rear bumper) muffler and run a straight thru pipe, will that affect back pressure, I was guessing that it wouldnt affect the computer because it idled nicely (and the sound was quite nice) but just need to clarify before making any major changes.

Do a search for 'back pressure' and heaps of threads will come up.
One more recently regarding a duel exhaust had heaps of information explaining how 'back pressure' was really just an incorrect assessment for loss of power due to low velocity flow in the pipes due to pipes that are too big.

Read it, it will explain it all, and members who know what they're talking about have confirmed this.

okay after having a read, wrong choice of words, take out the back pressure issue and has anyone done the straight thru pipe mod or has everyone replaced that rear muffler with a hotdog or high flo muffler???

not a 1st gen magna, but my borthers old cortina had a hotdog exhaust

was a ***** for cruising as it would just drone on and on and on and on
but going up and down gears was hella sweet, and our most favouritable moments were going thru those story car parks, and the exhaust setting off all the car alarms lol

im running this setup, lukey extractors/high flow cat/no middle resinator/lukey turbo muffler 2.25" pipe sounds sweet

Ive got lukey extractors, and wasnt going to change anything about the front muffler or the cat rather just remove the rear muffler, then run a straight thru pipe as I said, with no other mufflers or hotdogs, basically is this legal and has anyone else done this??

front muffler controlls the noise lvl rear controls volume, mine is still rather loud (rattles the tin in the carport roof) doing what you say would probly have you off the road in a week

ive got lukey headers 4 into one, 2 1/4 inch zorst into a lukey ultraflo muffler. sounds pretty sweet though i think the flexi pipe is vibrating when its a bit cold at startup. cant say i noticed any power gains but maybe when the stage 2 cam and valve springs goes in itll make more use of it. the sounds it makes are great, especially when it burbles and pops when downchanging, i feel like a rally driver :cool:
check out my video's on my cardomain profile. theres a video of my dyno run, although the flexi pipe was virating a bit.
if your lazy just click on the link to the video
TM-Terror Dyno Run (http://members.westnet.com.au/mccormack/tmterror.asf)

Wow I do like the sound of your car TM Terror! that is choice. So you have the one muffler then?

Man I thought what I wanted to do would be quick and easy ... obviously not then!!!

Might try the ring around and see what the 'pro's tell me'

well ive got the stock headers connected to the cat, which is then flanged into 2.5" mandrel bent piping, brand new flex piece into a hi-flow lukey muffler, then into a hi-flow supercat muffler on the rear and everyone reckons my car sounds really good. if anything, its still alittle too loud. (2.5" mandrel bent is too big for a stock car with minor mods, i have a turbo sitting here and i was never going to get a 2" mandrel bent, then get another 2.5" mandrel bent wen i got the turbo on for more flow)

wen i had the above system without the lukey hi-flow mid muffler, it would sound beefcake underload but wen u changed gears or backed off, u couldve shot urself to get away from the noise it made. sounded like a thousand tiny backfires... kinda like vrroooooooommm BLAAAHHHHHH... it didnt sound nice at all.

but no, ive never heard wat it'd sound like without the rear muffler. so u are saying u have the stock exhaust system with lukey headers? just get a hi-flow muffler put on the rear.

Wow I do like the sound of your car TM Terror! that is choice. So you have the one muffler then?

Man I thought what I wanted to do would be quick and easy ... obviously not then!!!

Might try the ring around and see what the 'pro's tell me'

thanks :D
yeah its just the muffler at the rear, i got the whole lot installed by a pro for $565
all that noise yet it only makes 80HP :redface:
although in the car's defense, i havent got the tools to see what mixutre im running or where its best to have the timing.

cool guys thanks for all the info, will invest the dollars and go for either just the hi flo muffler ( are they as big as the stock one? coz i hate that thing!!) or put a 2 inch sports system on the old girl.

i'd go 2 1/4" like i did go. ive got that catback with a lukey res and a lukey hi-flo, the muffler is tiny compared, its about the size of the back muffler on the new hundred series land cruisers (the oval mufflers not the round ones) its about 2" high and 10" long from my memory but ive never measured it and havent looked in a while so it could be half as big or four times as big.