Any advantage to larger/straight pipe on 1.6 NA?

[motomike33y]

I've read about the advantage w/turbo to increasing the exhaust flow, but is there any advantage to putting 2.25 straight pipe on regular 1.6 NA engine?  not trying right now, but thought for the future.  insight appreciated.  thanks.

[ibizz]

yes at least breath more easy , and increase torque

[Bugsy_malone 666]

To Some extent the NA Diesel should be treated in a similar manor to a Gas engine with regards to tuning in some respects, better gas flow in and out of the engine and a little extra fuel will help you out. I am not sure though if a proper 4 brand manifold with give you much benefit though, but certainly a less restrictive exhaust will help. They do become very loud though!

[R.O.R-2.0]

the toilet bowl downpipe is one of the biggest restrictions..

get a better manifold, like a dual downpipe unit, and run a muffler..

i had a glass pack on my rabbit, and it was RETARDEDLY loud.. well, that may have had something to do with the header too..

[rodpaslow]

I go with ROR, I had a hole in exhaust a year ago.  If you thought a gasser was loud with a straight-pipe, just wait till you do a 1.6 NA.  You will need serious ear plugs to drive the car. 

[R.O.R-2.0]

a flowmaster 40 or 50 series would probably sound pretty bad ass on a VW n/a

[motomike33y]

yeah, it's loud enough now with the normal noise from the engine compartment-don't know if I could handle having to wear earplugs.  Does muffler assist or hinder with the larger diameter pipe?

[8v-of-fury]

currently have a straight pipe on my 1.6 N/a with a glass pack. Oh my gawd does it sound raspy when you get her up in the revs. 4000 sounds superb!

[RabbitJockey]

the toilet bowl downpipe is one of the biggest restrictions..

get a better manifold, like a dual downpipe unit, and run a muffler..

i had a glass pack on my rabbit, and it was RETARDEDLY loud.. well, that may have had something to do with the header too..

diesels actually had the bigger toilet bowl, i think the biggest restriction is the pin prick stock exhaust, 1 5/8"s, what a joke, also the stock intake setup is very restrictive, both were designed to reduce engine noise.  i bet an na diesel, with governor mod (or especially with a giles pump), a bigger exhaust, and gas intake manifold would be equal or better than an equivalent sized gasser as far as performance, actually i think tylers dyno already proves that.

[8v-of-fury]

Trev i do believe you are right, Tyler's car was a Giles pump, stock intake stock exhaust. And he pulled some mad power throughout the whole range.

[rabbitman]

The guy that's making my valves told me that a rabbit with a ported NA diesel will keep up with a gasser rabbit.

If you are never going to get a turbo then I would NOT recommend going larger than 2", maybe 2 1/4" at the biggest. My NA rabbit has is 2.5" all the way back with a homemade muffler by the shifter and a thrush baffle one in the rear and the noise, while not painful, will leave my head ringing after less than a 100 miles. When I had the vnt15 installed and NO muffers it sounded awesome and wasn't too loud at all.

[R.O.R-2.0]

currently have a straight pipe on my 1.6 N/a with a glass pack. Oh my gawd does it sound raspy when you get her up in the revs. 4000 sounds superb!

hondas are raspy.. VW diesels are rappy..

the pipes rap on a diesel..

and they start rappin at about 1200rpms.. least they did on my car.

i couldnt shift, or take off without rappin my pipes..

almost the same setup as jeremy.. a header, feeding the stock exhaust system, and then a glasspack at the end..

[R.O.R-2.0]

The guy that's making my valves told me that a rabbit with a ported NA diesel will keep up with a gasser rabbit.

If you are never going to get a turbo then I would NOT recommend going larger than 2", maybe 2 1/4" at the biggest. My NA rabbit has is 2.5" all the way back with a homemade muffler by the shifter and a thrush baffle one in the rear and the noise, while not painful, will leave my head ringing after less than a 100 miles. When I had the vnt15 installed and NO muffers it sounded awesome and wasn't too loud at all.

my n/a diesel would almost keep up with my 85 GTI.. so i bet it would keep up with a stock rabbit. i had no porting or anything done, it had a header, a better air intake, a cranked up fuel pump.. and probably a few other little things i cant remember..

[motomike33y]

why would the straight pipe be quieter w/turbo than without?  or is an esthetic thing that the turbo noise blends in and the exhaust note isn't noticeable?

[RabbitJockey]

why would the straight pipe be quieter w/turbo than without?  or is an esthetic thing that the turbo noise blends in and the exhaust note isn't noticeable?

turbos just act as a muffler, the first thing i noticed after my turbo swap was how much quieter it was.  and then how much faster it was haha.

tyler did 48whp and 70wtq if you figure 18% drive train loss thats 56whp and 83wtq, looks like 1.6-1.7 gassers are anywhere from 60-75hp.  so some what comparable considering the vw diesels have a tiny exhaust and intake