Silvia Club of NSW

Why drive when you can drift?
It is currently Fri Mar 29, 2024 6:25 am

All times are UTC + 10 hours [ DST ]




Post new topic Reply to topic  [ 129 posts ]  Go to page Previous  1, 2, 3, 4, 5, 6, 7, 8, 9  Next
Author Message
 Post subject:
PostPosted: Tue Aug 08, 2006 11:16 am 
Offline
Moderator
Moderator
User avatar

Joined: Fri May 31, 2002 8:24 am
Posts: 5314
Location: The Shadows...
Car: MKV Golf
This is some really useful info guys. Keep it up and this thread can work it's way into the Technical Articles section.

_________________
The Golf is like an 16-year-old girl with big boobs. You know it's wrong but you can't keep away from her.


Top
 Profile  
Reply with quote  
 Post subject:
PostPosted: Tue Aug 08, 2006 12:21 pm 
Offline
T51 Hybrid
User avatar

Joined: Thu May 18, 2006 8:38 pm
Posts: 359
Location: Sydney
Car: 200SX
Actually come to think of it, if clearance is an issue, it'd probably be the T04E compressor cover being too large. So thus, maybe changing the GT28R compressor cover (aka "S15 compressor cover" like in the HKS GT-RS) would save a lot of space, and still accomodate the 71mm GT35 compressor. Hmmmmmm indeed.


Top
 Profile  
Reply with quote  
 Post subject:
PostPosted: Tue Aug 08, 2006 12:46 pm 
Offline
Takumi
User avatar

Joined: Fri Feb 01, 2002 11:00 am
Posts: 4779
Location: building!
Car: Silvia
it might reduce the efficiency a lot though.

It may work really well, but there's a big possibility of turning a good turbo into a dud!

_________________
The Engine Whisperer - fixer of things


Top
 Profile  
Reply with quote  
 Post subject:
PostPosted: Tue Aug 08, 2006 12:50 pm 
Offline
Twin T04
User avatar

Joined: Wed Sep 25, 2002 1:15 am
Posts: 931
Car: green datto
It's also going to hack around the comp map most likely affecting efficiency in the high flow zones of the map. In the end you've just built a 2871 which probably explains why they're popular :)

Regarding the back end, personally, I wouldn't be keen. There are two big advantages of running a "proper" GT30 rear end, 1) having a large external wastegate which you can hold closed longer and open at the latest possible moment to maximise boost response, 2) Having a perfect exit from the turbine to ensure peak flow to maximise power and response. Your idea will compromise both and I reckon you'd have to have a long think about exactly what you'd gain by running your custom arrangement over a standard divided T2 rear housing with a well designed dump. My gut feel is that you'd end up with a pretty poor cost/perfomance tradeoff in comparison to a factory 2871 in the standard position or a highmounted 3071.


Top
 Profile  
Reply with quote  
 Post subject:
PostPosted: Tue Aug 08, 2006 6:59 pm 
Offline
T28 Hybrid

Joined: Wed Apr 12, 2006 11:40 pm
Posts: 77
Car: S14a
i ws wondering if the gt3071r is the same as the gt30r? or are they two totally different turbo?


Top
 Profile  
Reply with quote  
 Post subject:
PostPosted: Tue Aug 08, 2006 8:55 pm 
Offline
T51 Hybrid
User avatar

Joined: Thu May 18, 2006 8:38 pm
Posts: 359
Location: Sydney
Car: 200SX
I guess you're right on the money omg. No point piss fartin around, might as well go the raw deal or stay with a GT28 framed turbocharger. Also I've read the GT T3 housings are more efficient than the older style T3 5 bolt housings (which I was listing before). OK time to hunt around for a decent manifold. SSAutochrome anyone? LOL

The difference between the GT30R and the GT3071R is that the GT30R uses a slightly bigger compressor (76mm GT40 comp) so is capable of a bit more power with more lag. They both use the same turbine (GT30 60mm). (Don't get confused with the T25 style GT3071-WG abominations, which are not recommended.)


Top
 Profile  
Reply with quote  
 Post subject:
PostPosted: Wed Aug 09, 2006 12:51 am 
Offline
T28 Hybrid

Joined: Wed May 05, 2004 11:34 pm
Posts: 98
Car: s15
ATT: Dumhed, OMG :D

So what kinda boost could you run reliably on a stock s15 motor with a top mount 3071 Setup? if the vehicle already has a pfc, cams and all the rest of the supporting gear, would it even be worth doing at all?


Top
 Profile  
Reply with quote  
 Post subject:
PostPosted: Wed Aug 09, 2006 2:17 pm 
Offline
Twin T04
User avatar

Joined: Wed Sep 25, 2002 1:15 am
Posts: 931
Car: green datto
I wouldn't have a problem running 15-16psi as long as everything was done properly.


Top
 Profile  
Reply with quote  
 Post subject:
PostPosted: Wed Aug 09, 2006 2:57 pm 
Offline
Admin Team
Admin Team
User avatar

Joined: Sun Aug 03, 2003 3:27 pm
Posts: 3870
Location: here
Car: Hello Kitty!
Just to clarify omg,

Are you saying 15-16 because you know roughly what power it will make at that boost with the mods listed and anymore will make the engine a bit of a grenade, or you just wouldn't run more boost ( no matter what turbo)on a stock bottom end, period?

_________________
meh


Top
 Profile  
Reply with quote  
 Post subject:
PostPosted: Wed Aug 09, 2006 3:10 pm 
Offline
Quad T66
User avatar

Joined: Wed Oct 15, 2003 3:36 pm
Posts: 2938
Car: 200sx
16psi with a small turbo is a bit weak :P

i think bottom end strength is more related to combustion chamber pressures rather then inlet pressures, and combustion pressures are more directly related to airflow/power rather then boost, right.

anyways 16psi sounds boring with such a large turbo ;)


Top
 Profile  
Reply with quote  
 Post subject:
PostPosted: Wed Aug 09, 2006 3:29 pm 
Offline
Takumi
User avatar

Joined: Fri Feb 01, 2002 11:00 am
Posts: 4779
Location: building!
Car: Silvia
that turbo will still make pretty big power at that sort of boost level.

Power output in itself is not the main killer of engines, but once you're making more than a certain amount the reliability will certainly go down.

Higher boost does stress things more (such as the head gasket), and makes the engine more prone to detonation.
If you're running a larger turbo it will put less of a restriction on the exhaust side of the engine, which will improve the overall flow efficiency and power without really increasing stress too much.

The engine should be more reliable running 15psi on a large turbo than it would be running closer to 20psi to get the power out of a smaller one.

_________________
The Engine Whisperer - fixer of things


Top
 Profile  
Reply with quote  
 Post subject:
PostPosted: Wed Aug 09, 2006 3:50 pm 
Offline
Quad T66
User avatar

Joined: Wed Oct 15, 2003 3:36 pm
Posts: 2938
Car: 200sx
yeah it may make decent power, but its not as good as it could be. and when you have such a large turbo you may as well make the most of it or whats the point, too much lag for not much relative gain

i would always try using the smallest turbo possible for the target power. imo its not worth going larger turbo to run less boost to make the same power as a smaller turbo for reliabilities sake. the tune is important here too though when running alot of boost

with the head gasket reliability on SR's, from experience mine has been pretty good. no problems thus far and ive been running 1.3-1.4bar in my engine with stock head bolts and gasket. i think detonation is the major cause of people who have gasket problems at boost levels lower or equal to that, which again comes back to a decent tune. as reference i never get knock levels over 15 on my PFC


Top
 Profile  
Reply with quote  
 Post subject:
PostPosted: Wed Aug 09, 2006 4:23 pm 
Offline
T28 Hybrid

Joined: Wed May 05, 2004 11:34 pm
Posts: 98
Car: s15
Thanks alot, dumhed & omg for ya valuable input as always!

The reason why I m asking these questions, is because the s15 I am purchasing has already has a full 3037r top mount turbo setup, and I was lookin' for something with a little bit less lag, and still plenty of usable power to replace the 3037r with, which is on a stock s15 motor at the moment. So I m hopin' that the 3071r would be a good option on a stock motor, with all the necessary supporting gear, if I am not mistaken. Please correct me if I am wrong.


Top
 Profile  
Reply with quote  
 Post subject:
PostPosted: Wed Aug 09, 2006 5:32 pm 
Offline
Takumi
User avatar

Joined: Fri Feb 01, 2002 11:00 am
Posts: 4779
Location: building!
Car: Silvia
I think it'd work pretty well actually.

It's not going to be lagless, but it'll be pretty good considering the power it'll make.

_________________
The Engine Whisperer - fixer of things


Top
 Profile  
Reply with quote  
 Post subject:
PostPosted: Wed Aug 09, 2006 6:10 pm 
Offline
Token Old Guy
User avatar

Joined: Thu Jun 16, 2005 5:09 pm
Posts: 2849
Location: At my desk
Car: 180SX
DumHed wrote:
I think it'd work pretty well actually.

It's not going to be lagless, but it'll be pretty good considering the power it'll make.


What about something like mine Andrew? Sounds like it would fit the bill.

_________________
I didn’t break it, I just modified the operational status...
There are 10 types of people in this world, those that understand binary, and those that don't.


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 129 posts ]  Go to page Previous  1, 2, 3, 4, 5, 6, 7, 8, 9  Next

All times are UTC + 10 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 19 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group