home register FAQ memberlist calendar

Go Back   Turbobricks Forums > Mechanical > performance & modifications

Reply
 
Thread Tools Display Modes
Old 05-02-2019, 11:48 AM   #1
drift256
Board Member
 
Join Date: Feb 2019
Default 90+ Manifold porting

-Hey guys, I recently picked up a 15G that I will be swapping in a few weeks. While I've got the manifold out I was to port it a bit along with the exhaust housing on the 15G.

-My question is should I purchase a T3 turbo gasket and port the housing and manifold to match that, then use the T3 gasket when I mount the turbo? I haven't taken the turbo off yet so I don't know what the gasket looks like. I want to make sure I have all the necessary parts before getting started.

-Also, should I go ahead and get a gasket set for the manifold to head, and a new one for the turbo the the downpipe? Thanks for the help.
drift256 is offline   Reply With Quote
Old 05-02-2019, 12:09 PM   #2
Jerd
Board Member
 
Jerd's Avatar
 
Join Date: Mar 2008
Location: Vancouver WA
Default

Search and you will find many pictures and discussions covering this topic already.

https://forums.tbforums.com/showthread.php?t=233098

Quote:
Originally Posted by Roy 940 View Post












Her is the pics, as said...
Jerd is offline   Reply With Quote
Old 05-02-2019, 04:57 PM   #3
drift256
Board Member
 
Join Date: Feb 2019
Default

Yes I have read through that thread. What I need to know is if you then use the t3 flange when you reinstall the turbo on the manifold. Thanks.
drift256 is offline   Reply With Quote
Old 05-02-2019, 05:07 PM   #4
Sjeng
Board Member
 
Sjeng's Avatar
 
Join Date: Sep 2017
Default

Just use the OE volvo gasket. No reason to use a T3 gasket.

Also, do not port it as big as shown above. Unless you think killing gas velocity is a good idea.

It will be fine when you match the manifold to the turbine inlet, in my opinion.
Sjeng is offline   Reply With Quote
Old 05-02-2019, 07:32 PM   #5
Jerd
Board Member
 
Jerd's Avatar
 
Join Date: Mar 2008
Location: Vancouver WA
Default

Quote:
Originally Posted by drift256 View Post
Yes I have read through that thread. What I need to know is if you then use the t3 flange when you reinstall the turbo on the manifold. Thanks.
Like Sjeng said use the right gasket. Or just use Rtv...

Quote:
Originally Posted by Sjeng View Post
Also, do not port it as big as shown above. Unless you think killing gas velocity is a good idea.

It will be fine when you match the manifold to the turbine inlet, in my opinion.
Good opinion. Porting to that extent would probably promote scavenging of the exhaust gasses along with a decrease in velocity.

Last edited by Jerd; 05-02-2019 at 08:07 PM..
Jerd is offline   Reply With Quote
Old 05-02-2019, 08:03 PM   #6
dl242gt
Happy playing the blues
 
dl242gt's Avatar
 
Join Date: Jun 2002
Location: S NJ, a suburb of Phila.
Default

Does your 15g have the volvo shelf on the turbine inlet? Then I would use the T3 gasket as a guide to make the hole as large as the gasket opening. Then mount the turbo without a gasket fitted to the shelf on the manifold which is made to mount up to Volvo turbos without a gasket.
dl242gt is offline   Reply With Quote
Old 05-02-2019, 08:55 PM   #7
drift256
Board Member
 
Join Date: Feb 2019
Default

I’ll take a look at it. I believe it’s a 15g from an 850 but from what I remember it was a flat mounting surface.
drift256 is offline   Reply With Quote
Old 05-03-2019, 12:54 PM   #8
VB242
F*ck 12
 
VB242's Avatar
 
Join Date: Sep 2011
Location: In my 15x20 Corona cell
Default

I sprayed my turbo/manifold interface with engine paint per my machinist's recommendation. It doesn't seem to leak even with the boost turned up to 25psi
__________________
"i will destroy all of you!"
-Sheldon Plankton

Booty Scooty
https://youtu.be/i4oAOZ8nbq4
VB242 is online now   Reply With Quote
Old 05-03-2019, 01:03 PM   #9
linuxman51
BRANDSCHUTZVORSCHRIFTEN!
 
linuxman51's Avatar
 
Join Date: Dec 2002
Location: mont, AL
Default

if the 15g is a volvo unit, you don't need to port anything-it's already oval. I'd like to see some ebr numbers before and after on these sort of massive port jobs right there at the collector... I suspect it's a rather large waste of time.
__________________
"They bum rushed them in their own crib, they drank all their beer, they partied with their ladies and they left with the trophy"

Now with in-house Dyno tuning!

Megasquirt Tuning!
Plug and play LH 2.4 Megasquirt, now with stealth mode!
linuxman51 is offline   Reply With Quote
Old 05-03-2019, 09:20 PM   #10
boostin'xr4
OV FIRE
 
boostin'xr4's Avatar
 
Join Date: Apr 2008
Default

Quote:
Originally Posted by Sjeng View Post
Just use the OE volvo gasket. No reason to use a T3 gasket.

Also, do not port it as big as shown above. Unless you think killing gas velocity is a good idea.

It will be fine when you match the manifold to the turbine inlet, in my opinion.
I dont see how porting the manifold like that would kill exhaust velocity with how high the EBR with that tiny 15g would be. I would suspect the manifold out flows turbine housings nearly double that size.
__________________
'74 145 - B20, M40, Weber 38DGES
'82 244t - B21ft, MS, E85, H cam, 50trim, T5 swap, etc.
'94 945t - MS, E85, 1500cc's, top mount, 6262, Cd009, etc.
boostin'xr4 is offline   Reply With Quote
Old 05-12-2019, 12:34 AM   #11
klr142
Turbo, what?
 
klr142's Avatar
 
Join Date: May 2004
Location: OR
Default

Erland Cox says you don’t want to do this. There’s no reason to take a small hole, make it twice as large, only to neck back down into a small hole again. That makes an expansion chamber to slow the gasses down but then try and speed them back up again by restricting them down into a tiny snail. A better thing to do is to keep the small 90+ opening and make the turbo’s inlet the same size by filling it in. But, that’s obviously more complicated than just removing material.
klr142 is offline   Reply With Quote
Old 05-12-2019, 06:49 AM   #12
740atl
educator monkey
 
740atl's Avatar
 
Join Date: Apr 2010
Location: USA
Default

Quote:
Originally Posted by klr142 View Post
Erland Cox says you don’t want to do this. There’s no reason to take a small hole, make it twice as large, only to neck back down into a small hole again. That makes an expansion chamber to slow the gasses down but then try and speed them back up again by restricting them down into a tiny snail. A better thing to do is to keep the small 90+ opening and make the turbo’s inlet the same size by filling it in. But, that’s obviously more complicated than just removing material.
Thank you!!!
740atl is offline   Reply With Quote
Old 05-12-2019, 03:53 PM   #13
klr142
Turbo, what?
 
klr142's Avatar
 
Join Date: May 2004
Location: OR
Default

Haha, sure! He posted it on here somewhere, but it’s hard to search for...
klr142 is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump


All times are GMT -4. The time now is 10:11 AM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2020, vBulletin Solutions Inc.