Exhaust Merging options and Scavenging

[BigSteve]

I think Y-Pipes have arrived from the US, now waiting on the tips and new muffler (no plural) all about half the cost it would have been locally.

Hopefully in a few weeks I'll have a clip with a new exhaust. I have to leave room for a 2nd muffler/resonator in the middle pipe in case 1 muffler is too loud.

It'll sound beefy

 

[BigSteve]

Looks like the guy sent my the wrong damned Y-pipes, Too bloody expensive to send em back to the US and order new ones now..

 

[BigSteve]

Well the new exhaust is done, It sounds far more exotic now with the new set up, and I gotta say I really like the sound of it under load, but the cammed idle has quietened down a load.

The power curve has changed, where as I used to feel a surge of power at 3500 rpm, I can't quite feel that any more. I'm not sure if that's due to more power lower in the rev range, or less power above 3500 rpm.

Hard to tell as the exhaust note changes the entire feel of the car, gained back a lot of the smoothness.

 

[samsdad]

I've had extractors made. Try Y type. Will need to talk to the supplier and if he's agreeable can I steal the Celsior at some point to se if what we have done will fit? Mine didn't come back from last lend out but the Surf sounds totally schmick with them on

 

[BigSteve]

It's possible, I'll have to drop in to the shop sometime soon and we can have a look see, extractors would be a nice addition if it wasn't such a head ache in these things

 

[BigSteve]

I discovered the Y-pipes I supplied are still in the boxes in my car, I have no idea what sort of merges the guys at the shop used until I can get under my car to have a look.

 

[samsdad]

We've played with the extractor design a little bit on the latest hilux conversion after a wee error got made as we'd jigged up on one that was formerly a diesel and the current build was 3RZ petrol. Due to this the engine mount brackets sit further back on the chassis so what was jigged up and made caused all sorts of cursing, swearing and gnashing of teeth...

Anyhow given that this is a 4wd and not a Celsior/LS we had a little play and made the primaries longer, well as long as possible in this instance and that people is the secret. We acheived the result that Steve was chasing with his cams and pardon my french but f@#k me!! I've never had a 1U in a 4bie with stock engine and ECU give such a punch between the shoulder blades as this one does. You can't take off quickly in it without spinning the wheels upto 4th gear ( Manual, 3.7 diffs and 31 inch tyres) so I'd hate to try it on a wet road. Gave it back to the owner today and on the way home went past him going in the other direction. All I could see was this big grin in his windscreen

 

[BigSteve]

Sounds like they did the Job!

My celsior is starting to act strange, running super rich when cold and sputters if I try to take off before it's warm. I think the ECU is getting confused, need to reset it I guess.

Seems as though it's using some oil also, I had to top it up not long ago.

 

[BigSteve]

Well, as much as I've been trying to convince myself that I like the new exhaust, I'm just not feeling it. It does have a nice sound at certain RPM, but it's still not the sound I was after, not sure if it's the setup or just the Genie Hotdog style muffler in the center, but it sounds a bit too tamed now, maybe too close to a 6 cylinder sound.

I'm fairly sure I lost a lot of top end power for a small low end gain, so I think with both sound and power I want somewhere in the middle of the 2.

I think I'll end up changing to a Twin 2.25" system with an X-pipe, larger pipe will give some of the deep note back that I lost, and I'll have to supercharge in future to make use of the flow. My issue is placement of mufflers again. I guess I'll have to put 2 mufflers on the back again and just hope 2 mufflers + x-pipe isn't too quiet.

 

[Bushwhacker]

Here's some videos of my latest one, stock '96 LS400 manifolds, 2" pipe from the flanges into a 'X' pipe then all the way to the rear end with two Flowtech Raptor mufflers with BMW X5 tailpipe trims. No Cats.
Excellent throttle response from idle.
http://s8.photobucket.com/albums/a4...lsior/?action=view&current=scenicdrive033.mp4

http://s8.photobucket.com/albums/a4...ior/?action=view&current=october2011001-1.mp4

Video from the owner, driving through the Dublin Port Tunnel in Ireland on his way home to Belfast...

http://s221.photobucket.com/albums/dd142/gbv2/?action=view&current=12cf9945.mp4

 

[JBrady]

Well, as much as I've been trying to convince myself that I like the new exhaust, I'm just not feeling it. It does have a nice sound at certain RPM, but it's still not the sound I was after, not sure if it's the setup or just the Genie Hotdog style muffler in the center, but it sounds a bit too tamed now, maybe too close to a 6 cylinder sound.

I'm fairly sure I lost a lot of top end power for a small low end gain, so I think with both sound and power I want somewhere in the middle of the 2.

I think I'll end up changing to a Twin 2.25" system with an X-pipe, larger pipe will give some of the deep note back that I lost, and I'll have to supercharge in future to make use of the flow. My issue is placement of mufflers again. I guess I'll have to put 2 mufflers on the back again and just hope 2 mufflers + x-pipe isn't too quiet.

Steve, did you ever look at the pipes your shop installed? Have pictures? Not sure of the design of the Genie muffler but it may be like the standard glasspacks like Cherry Bomb's that have louvers punched into the flowpath creating huge restrictions.

You NEED...
Good merges, Y pipes.
Good mufflers
Good transitions.

Post some pics if you can. Unless they really created a mess under your car (possible) you may not need to redo to gain back your power (or more) and get the sound you want.

Post a diagram of what you are thinking.

 

[BigSteve]

I haven't had a chance to jack it up yet, bit too low to get under and have a look. This muffler (for the middle) was the only solution apparently as mine wouldn't fit without hanging too low (I think it would have only just fit) but he mentioned when I first got there he didn't like using products customers bring in themselves, or they have to charge more for the work.

I never saw the inside of the muffler, but I assume it's a glasspack, looks the same. "Hotdog" I think most people call them.

I had no idea they didn't use my Y-pipes though, so there's a good chance they are inefficient collector types.

All I was thinking of changing to Just from cats, 2.25" pipe into X-pipe behind the transmission, then 2 separate pipes all the way to the back into a muffler on each side.

I do want to see what it sounds like without the centre muffler (Has 2 thin resonators just before the tips at the moment) but it'll have to wait until I get tyres this time. Oh and this exhaust is also leaking now, the cammy idle must be doing it.

I have a spare magnaflow muffler and 2 magnaflow y-pipes at the moment

If I could find a decent muffler small enough to fit where the old middle resonator was I'd probably try that first and fit my Y-pipes.

 

[JBrady]

Steve, simply replace the center muffler with a piece of 2.5" tube. Cheap, simple, effective.

You stated that the shop that installed your system didn't use your Y section you purchased. There is NO TELLING what they did and I have the suspicion that they used crush bent 2.0" pipes into a cobbled up Y section with WHO KNOWS what kind of function. Crush bent 2.0" pipes can act as much smaller pipes with in some cases the effective area of 1.5" pipes.

Get your car on a lift and get some pictures.

On my LS400 I dropped off everything after the center resonator.
Running just the front Y and resonator was LOUD. Sounded like a 7 liter engine at idle. I am afraid that you are chasing your tail and without knowing what you currently have are in no position to evalute changes.

 

[BigSteve]

Yah I would love to take out the middle muffler but I live in a block of apartments, and the noise would be far too loud for my neighbours, even if it did sound really nice.

If I just replaced that with a pipe (providing the 2 y sections are ok) then I still need to find mufflers for the back 2 pipes, as the resonators probably won't make the exhaust much quieter than just straight through pipes.

 

[BigSteve]

http://youtu.be/0Rl628DAqGY

Finally got a clip of the current setup.

Tips aren't straight unfortunately.

 

[samsdad]

I think that you are going shopping on eBay shortly and buying what I am awaiting to turn up.. Apexi SAFC-2. Just fitted one to an LS and then got Glenn to do the zorrst.. On the LS... Wow!!! and that is before tuning the apexi. And yours has cams with great big hairy nuts. Note on the LS is very subtle but man does she fly with the apexi and behaves as such, Just got the Surf back from custom exhaust and she's absolutely evil

 

[BigSteve]

I think that you are going shopping on eBay shortly and buying what I am awaiting to turn up.. Apexi SAFC-2. Just fitted one to an LS and then got Glenn to do the zorrst.. On the LS... Wow!!! and that is before tuning the apexi. And yours has cams with great big hairy nuts. Note on the LS is very subtle but man does she fly with the apexi and behaves as such, Just got the Surf back from custom exhaust and she's absolutely evil

I need something more like a Haltech platinum so I can raise the Rev limiter for those cams. I don't know if SAFC-2 will do it? I was planning on a Haltech PS1000/2000 also with mafless, removing the MAF is 10-15 hp gain itself I was told by a few people.

 

[BigSteve]

Well long time no see! I've finally been able to reset my password. Someone new took over the forums?

Anyhow I threw together a video that shows a bit more specifically the exhausts I used and how they sounded.
I have a nicer condition Ucf11 now (cf pack) so this motor will probably be coming out and getting ready to put in the new car.

 

[BigSteve]

The Latest experiment.