The 18R-GTE reference manual ...

[o_man_ra23]

I am hoping to make the exhaust manifold over the christmas break, but better get my arse into gear getting flanges

[o_man_ra23]

Well, this is the approximate postion the turbo will be on


And this is the first section of my dump pipe

and from inside


Note the separate chambers for the wastegate and main outlet to help spool it. Oh, and the fully Ghetto spec wastegate chamber hole... it should work (hopefully)

Happy new years all. Keep an eye on my RA28+18R-GTE thread (linked in my sig) for more detail on the build.

[Steve M]

Slidin23,

Have you been in touch with Brenton from Fours 'n' More?
He would be one of the best guys to talk to about 18Rg turbo projects, he's given me some good advice about mine (still building) and he has contacts for forged pistons. I got my pistons from Atomic Speedware, Arias customs in the USA.

Brenton is also a Microtech Dealer and deals with tuning 18RG's a fair bit.

[JustenGT8]

Well, this is the approximate postion the turbo will be on


And this is the first section of my dump pipe

and from inside


Note the separate chambers for the wastegate and main outlet to help spool it. Oh, and the fully Ghetto spec wastegate chamber hole... it should work (hopefully)

Happy new years all. Keep an eye on my RA28+18R-GTE thread (linked in my sig) for more detail on the build.

Bad bad bad mate....all that will do is give you horrid overboost spikes.

If you want improved spool, you achieve that by controlling the WG actuator.....m,many ways i can run you thru?

For the actual DP, get the WG flow path as large and as neat as you can to get the best boost control.

I don't mean to sound harsh but what you have there is really really crap

[o_man_ra23]

Haha, yeah I knew it wasnt great, but im not after large boost or anything so didnt think it mattered all that much. I have 2 options, improve the hole that goes to the main pipe, or cut the barricade out completely and leave it an open void like OEM. Improving the hole will be more work (and I will probably need a new diegrinding burr), but will it be any of an improvement over having just a void?? Thanks for any advice, I am still learning turbo systems. For the 3S, I will just buy a ready made stainless dump.

[JustenGT8]

Best option with what you have is to take out the separating plate completely. If you have the room i would try and merge the WG side more gradually into the main pipe as well.

I ran a similar style DP on my white GT4 at one point and gave a stable 19psi from the CT20B.

[o_man_ra23]

Will see how I go, that DP will be cut short as it is getting dangerously close to the firewall. Perhaps I should drop the RG into the front of the 23 to dummy it all up??

[timbosaurus]

Haha, yeah I knew it wasnt great, but im not after large boost or anything so didnt think it mattered all that much.

less boost = more wastegate flow = more restriction from tiny hole = more boost creep/spikes.

I was going to say something before Justen jumped in, but figured you'd discover eventually

Out of curiosity, did you use a MIG or an Arc welder?

[o_man_ra23]

Mig... and I am still getting used to it. Some of the welds actually look quite professional (though some look like a chicken's scratchings )

[RA28tragic]

So what happened to RA 23? Did he build a turbo RG or not??? Jeez I thought I had a short attention span. Hey look a rock!!!!

[thechuckster]

owen, your dump pipe needs to look something like this:

showing how waste-gate pipe merges


how the turbine and wastegate outlets are separated

[Gold28]

I just found this thread and will have a read through the whole lot but I just thought I would reaffirm what Justin said about your dump pipe Owen. Regardless of what boost you plan on running, it is important that the wastegate gets good flow otherwise it will never be able to control the boost properly.

Many of the GT4 guys have had a lot of problems with boost control once thay have fitted free exhausts and an aftermarket dump. You have the advantage of a lot more space for your dump pipe so make it big and a nice gradual path into the main pipe.

Here is a photo of my cheepo dump that I am using. Not a great view of the gate path but it will give you an idea of what teh inside of the gate area looks like. No real probelms with it so far but I still have a standard exhaust fitted behind it. so there is still a reasonable amount of back presure.





Keen to follow your progress buddy.


Anthony

[o_man_ra23]

Unfortunately, I dont actually have the advantage of space, I have a firewall impeding it. I have taken the bridge out, and spent most of this afternoon with a dremel and a die grinding burr smoothing things out. Will take a photo tomorrow when I am finished.

[SillyCarS]

owen, your dump pipe needs to look something like this:

showing how waste-gate pipe merges


how the turbine and wastegate outlets are separated

that is very, very nice

[ra_28]

Has anyone used 22re with the 24.7cc postive dome in a 18rgte application yet. I took a set of forged wiseco ones down to have them fly cut and when they xrayed them to see how thick they were. If i had fly cut them i would only have had been left with about 2mm of thickness which would be no good for boost.

Does this theory of using off the shelf 22re pistons have holes in it or am i missing something.

Cheers
Alex