Worth Getting Split Dump Pipe?

[cree]

So I am looking at getting a dump pipe for my r33. It is just running standard turbo. I have read that if you are running big boost then split pipe will help but I just have the basic mods front mount, exhaust, fuel pump, boost controller. Would I be best off getting a split pipe or not?

[BakemonoRicer]

I run a CES Racing Front/Dump on my S15.

They make one for an R33 GTS-T as well. Quite pricey though.

http://www.cesracing.com.au/products_2.htm

[Mick_o]

Id say no just go for a bell mouth dump that will be sweet for the stocker mate

[cree]

Id say no just go for a bell mouth dump that will be sweet for the stocker mate

Thanks for the advice mate.

Edited September 13, 2013 by cree

[BakemonoRicer]

Thanks for the advice mate.

Personally, I'd go with the split, it's the best design for your setup.

The split design separates the waste gate gas flow away from the main pipe (where there is turbine exit flow) which is highly desirable for improved flow...

For internal gate, pretty well documented the split design provides less lag, more power, and better fuel economy

Bell mouth is cheaper to buy though...

My exhaust system (with the split front/dump) has netted me around 40rwkw, with improved response.

[cree]

Personally, I'd go with the split, it's the best design for your setup.

The split design separates the waste gate gas flow away from the main pipe (where there is turbine exit flow) which is highly desirable for improved flow...

For internal gate, pretty well documented the split design provides less lag, more power, and better fuel economy

Bell mouth is cheaper to buy though...

My exhaust system (with the split front/dump) has netted me around 40rwkw, with improved response.

Thanks. Makes my decision easy now.

[r32-25t]

Splits tend to cause a lot more turbulence in the face of the dump area and actually make boost come on later

We have proved this with 3 gtrs all running hks dumps on 3 different turbos, once we swapped over to bell mouth dumps on all 3 cars, they came alive

[cree]

Splits tend to cause a lot more turbulence in the face of the dump area and actually make boost come on later

We have proved this with 3 gtrs all running hks dumps on 3 different turbos, once we swapped over to bell mouth dumps on all 3 cars, they came alive

Could this be different for a GTST?

[BakemonoRicer]

R32-25t is talking about a split dump, whereas I am talking about a split front/dump pipe. They are different.

The split front/dump design (such as a CES Racing one) are the best for an internal gate setup.

[r32-25t]

R32-25t is talking about a split dump, whereas I am talking about a split front/dump pipe. They are different.

The split front/dump design (such as a CES Racing one) are the best for an internal gate setup.

do you have back to back proof on your own car or did you read the website?

[Got a Pulsar]

JJR Bellmouth $179 for Mild Steel or $199 for Stainless.

I got the Stainless. Much nicer feel than the stock dump with stock turbo.

Can't go wrong and if you decide to go split later, you can compare...

[r32-25t]

Could this be different for a GTST?

probably not, it's the flange face of the split dump pipe that causes all if the turbulence

[BakemonoRicer]

do you have back to back proof on your own car or did you read the website?

Sam off JDMST who owns an S15 that runs 1:06's at Wakefield, is running a CES split front/dump pipe coming off a .64 GT2860RS. His exact words are "they are the shit", and considering his uncle works at a reputable exhaust place in Campbelltown I'm sure he would of asked for his advice before using one.

The bloke who installed my exhaust has many years of experience and said he wouldn't have done anything different with the design of the front/dump currently on my S15. I should also mention he is friends with Skola and was taught how to weld by him as well.

[r32-25t]

So the answer to my question is no,

A dump pipe won't make you run a 1.06 around Wakefield, it's take a lot more parts then that and most of them aren't even engine related

And you have an option of a guy who said it looks pretty, has he done back to back testing on a car with dyno sheets?

[BakemonoRicer]

So the answer to my question is no,

A dump pipe won't make you run a 1.06 around Wakefield, it's take a lot more parts then that and most of them aren't even engine related

And you have an option of a guy who said it looks pretty, has he done back to back testing on a car with dyno sheets?

Sam only uses the best of the best parts for his car, hence why he is using the CES front/dump. It is the best from a design point of view for an internal gate setup (design in terms of benefiting performance, not looks btw - pretty obvious I was referring to that in the first place).

Also, there was the instance of someone using a HKS GT Extension Kit on an S15 (runs a Split Dump pipe, which then bolts to a 3 inch front pipe - this is not a split front/dump pipe). They went from 330ps with the HKS to 347ps once they installed the split CES racing front/dump pipe. So 17ps gain at peak power 6600rpm. At 5000rpm they were making 12ps more. Boost also came on earlier.

[r32-25t]

Look all I'm asking for legitimate proof of how great your dump pipe is, because I have 3 cars that have proved split dumps are not as good as bell mouth(not including all the xr6t boys who take them off and go to bell mouth design)

But another thing to add your your 1.06 argument is I have a mate with a momo steering wheel that has done sub 1 min around Wakefield and he thinks it feels great, does that make the momo a more cost effective mod then your dump pipe?

[r32-25t]

Basically I'm not going to argue with you, but in closing I will say this to the original poster.

I would never recommend a split dump as I have seen on my car and two other cars that bell mouth dumps do a better job

[BakemonoRicer]

Look all I'm asking for legitimate proof of how great your dump pipe is, because I have 3 cars that have proved split dumps are crap (not including all the xr6t boys who take them off and go to bell mouth design)

But another thing to add your your 1.06 argument is I have a mate with a momo steering wheel that has done sub 1 min around Wakefield and he thinks it feels great, does that make the momo a more cost effective mod then your dump pipe?

Once I do a dyno run in my car I will be happy to show you a dyno graph.

Split dumps are not long enough to actually get the sort of flow you will get from a split front/dump design.

Typical split dump

Ces split front/dump

[r32-25t]

I already said I'm not continuing with this, given my opinion to the OP that's it, leaving it at that

Ps. I can already see the restriction in the ces dump pipe pictured

[scotty nm35]

Personally, I'd go with the split, it's the best design for your setup.

The split design separates the waste gate gas flow away from the main pipe (where there is turbine exit flow) which is highly desirable for improved flow...

For internal gate, pretty well documented the split design provides less lag, more power, and better fuel economy

Bell mouth is cheaper to buy though...

My exhaust system (with the split front/dump) has netted me around 40rwkw, with improved response.

Quoting power figures on changing parts can be hit and miss unless you back to back test the parts, even then it is most probably bullsh1t as there are many restrictions to flow, and a little turbulence in the dump isn't going to change it much.

Bell mouth is bigger = better.

If the split dumps opened up into a 3 inch pipe for the turbo alone, they may be acceptable, but the wastegate path is nowhere near smooth enough or large enough.

Ditch the internal gate altogether imo, they cause much more restriction than external gate setups.