280zx l28 dual exhaust

[plexus]

can this be don an a 280zx with a Y pipe and is there enough clearence under the rear suspinion on the z for it (mind the typos im tired).

[dustin280zx]

http://forums.hybridz.org/showthread.php?t=102522&highlight=dual+exhaust

 

 

one of many threads in the exhaust section.

[plexus]

http://forums.hybridz.org/showthread.php?t=102522&highlight=dual+exhaust

 

 

one of many threads in the exhaust section.

 

thats great but im talking about the l28 (inline six) not a V8. i now it can be done on a V motor but what about the inline

[Pyro]

Will not sound very good.

 

Not enough sound pulses in the pipes with only 3 cylinders. That is why a one cylinder lawn mower doesn't have good sounding exhaust.

 

If duals can be run on a V8 then I'm sure they can be run on a inline 6. The rear suspension is the same with a V8 conversion or a stock liner, right?

[80LS1T]

Bart's car(in that link posted above) is an S30 not an S130, big difference...

 

You wont be able to fit true duals over the rear subframe unless you run really small piping which would kind of defeat the purpose of dual pipes. You can put a Y in after the subframe and run 2 pipes off of that. I did before I went to a V8, it looked pretty good and didnt sound to bad either.

 

Now I just run duals up to the rear subframe and then over the subframe is a single pipe into a straight through Magna Flow muffler.

 

Guy

[plexus]

^^that was kinda the same thought i was having except i wasnt sure as to where the Y would be placed before or after the sub just a thought ive been tinkering with since i havnt seen to many with that type of set up.

[David K]

You can do it with a 3 into 2 header with both pipes being 1 7/8" diameter. 2" is too big for 3 cylinders. You need to run the two 1 7/8" pipes side by side all the way back to the muffler, and have hangars made for each foot section of pipe and tack welded to the pipes themselves so they dont rattle against each other. I did that on my 79 for 2 years and it was really nice.

[plexus]

You can do it with a 3 into 2 header with both pipes being 1 7/8" diameter. 2" is too big for 3 cylinders. You need to run the two 1 7/8" pipes side by side all the way back to the muffler, and have hangars made for each foot section of pipe and tack welded to the pipes themselves so they dont rattle against each other. I did that on my 79 for 2 years and it was really nice.

that sounds like the same type of set up i seen on a g35, i think hks made that set up for it if i am not mistaken

[Daeron]

any twin pipe setup should involve a collector section, where all the exhaust is flowing through the same pipe, and then split off into two. it takes four cylinder per exhaust pipe to get anything remotely resembling proper scavenge effect, so anything less than an eight cylinder using full twin exhaust is losing serious power potential by doing so, and even a V8 benefits from the added scavenge effect of all eight cylinders running through one pipe. Note that I said power POTENTIAL; the increased scavenging of the exhaust pulses allows for much more aggressive tuning on the fuel and spark timing front.

[plexus]

any twin pipe setup should involve a collector section, where all the exhaust is flowing through the same pipe, and then split off into two. it takes four cylinder per exhaust pipe to get anything remotely resembling proper scavenge effect, so anything less than an eight cylinder using full twin exhaust is losing serious power potential by doing so, and even a V8 benefits from the added scavenge effect of all eight cylinders running through one pipe. Note that I said power POTENTIAL; the increased scavenging of the exhaust pulses allows for much more aggressive tuning on the fuel and spark timing front.

 

^^ any v motor that is high tuned does not need a collector, it will inhibit your full potential not running true dual exhaust. the difference is the diameter of the piping. if this was not the case then companies like hks borla ect would not make duals for cars like the 350z or g35 or for that matter porschewould not be dual exhaust. now a collecter is true for inline motors only, whether it is 4 6 or 8 cylinders. but then again i was first asking about the Y pipe set up for a L28 280zx i.e. 1 into 2 set up

[BRAAP]

Will not sound very good.

 

Not enough sound pulses in the pipes with only 3 cylinders. That is why a one cylinder lawn mower doesn't have good sounding exhaust.

 

 

 

There is a good thread going regarding exhaust pulses and exhaust notes that should help shed some light.

 

Exotic exhaust notes...

 

 

Here is just one of many first hand experiences with Z car exhaust systems from the standpoint of its tone and note. My ’75 280Z had a single 2.5”, then a true dual 1.75” and then a true dual 2” and then dual with a balance tube. No one ever noticed the difference in sound as I retained the same style and type of mufflers, though the pitch differences were ever so slightly different, attributable to the diameter of the of the pipes. Any difference in tone, quality, note, and pitch comes from the mufflers used, the diameter and overall length of the exhaust system, (including each cylinders run), number of cylinders, firing order and the time/order that the collectors, (if any collectors), receive that firing order, it has absolutely NOTHING to do with how many pipes are exiting the car. Adding a balance tube prior to the mufflers to a true dual exhaust will soften some of the harshness of the exhaust note, but only little and will be more pronounced on smaller diameter exhaust systems, most wouldn’t notice though.

 

 

 

If you are planning to use a “Y” branch, there is no real purpose of the dual other than for visual appeal as it exits the car.

 

HTH,

Paul

[Tom280z]

I'm going 2.5" off both headers than into one 3" all the way back it's gonna rock, she'll be roarin out of a flowmaster at the end:burnout:

[johnc]

any v motor that is high tuned does not need a collector, it will inhibit your full potential not running true dual exhaust. the difference is the diameter of the piping. if this was not the case then companies like hks borla ect would not make duals for cars like the 350z or g35 or for that matter porschewould not be dual exhaust. now a collecter is true for inline motors only, whether it is 4 6 or 8 cylinders. but then again i was first asking about the Y pipe set up for a L28 280zx i.e. 1 into 2 set up

 

Other then the the fact that companies sell dual exhausts for various cars, there's not one other true statement in that post. Collectors are critically important for performance tuning any high performance engine and at the higher levels of motorsports its common to find exhaust system builders spending $500 to $1,000 on the merge collectors alone.

 

http://www.spdexhaust.com/pdfs/02-11_Merge_Collectors.pdf

 

The wave tuning that merge collectors allows is key to scavenging the cylinders. Merge length, outlet, and divegent cone design is a science in and of itself and there are computers programs run by companies such as Burns Stainless that compute the exact merge collector dimensions based on 25+ engine variables.

 

http://www.burnsstainless.com/Xdesign/Race_Engine_Spec__Form/race_engine_spec__form.htm

 

A lot of cars run dual exhaust purely for cosmetic, marketing, and packaging reasons. Many tests on the normally aspirated Nissan VQ35 engine show they make more horsepower and torque with a properly designed single 90mm exhaust then any dual exhuast. Dual exhausts got their start decades ago mostly because larger exhaust sizes (3" and above) and the appropriate mandrel bending equipment was only in use in the aerospace industries.

 

TranAm cars of the 80's and 90's ran very elaborate 180 degree header designs that merged into a 5" single exhaust that went through the passenger seat area. Ultimately the rule makers banned those kinds of exhausts for safety reasons and the TransAm cars lost 10% of their horserpower and torque the following season.

[Daeron]

Other then the the fact that companies sell dual exhausts for various cars, there's not one other true statement in that post.

 

Thanks john, you're my hero

 

Thats essentially everything I was trying to summarize in my post.

[S130Z]

Daereon and JohnC are kust kidding around. If they were serious then this guy's could go from running 8 sec 1/4's to something crazy like 7 sec 1/4's if he ran a collector. But they were just kidding around.

 

[johnc]

Ever heard of Pro Stock, Pro Stock Motorcycle, Comp, Super Comp, Super Gas, Super Stock, Stock, and Super Street?